diff mbox series

[v2,02/14] soc: ti: k3: add navss ringacc driver

Message ID 20190730093450.12664-3-peter.ujfalusi@ti.com (mailing list archive)
State Changes Requested
Headers show
Series dmaengine/soc: Add Texas Instruments UDMA support | expand

Commit Message

Peter Ujfalusi July 30, 2019, 9:34 a.m. UTC
From: Grygorii Strashko <grygorii.strashko@ti.com>

The Ring Accelerator (RINGACC or RA) provides hardware acceleration to
enable straightforward passing of work between a producer and a consumer.
There is one RINGACC module per NAVSS on TI AM65x SoCs.

The RINGACC converts constant-address read and write accesses to equivalent
read or write accesses to a circular data structure in memory. The RINGACC
eliminates the need for each DMA controller which needs to access ring
elements from having to know the current state of the ring (base address,
current offset). The DMA controller performs a read or write access to a
specific address range (which maps to the source interface on the RINGACC)
and the RINGACC replaces the address for the transaction with a new address
which corresponds to the head or tail element of the ring (head for reads,
tail for writes). Since the RINGACC maintains the state, multiple DMA
controllers or channels are allowed to coherently share the same rings as
applicable. The RINGACC is able to place data which is destined towards
software into cached memory directly.

Supported ring modes:
- Ring Mode
- Messaging Mode
- Credentials Mode
- Queue Manager Mode

TI-SCI integration:

Texas Instrument's System Control Interface (TI-SCI) Message Protocol now
has control over Ringacc module resources management (RM) and Rings
configuration.

The corresponding support of TI-SCI Ringacc module RM protocol
introduced as option through DT parameters:
- ti,sci: phandle on TI-SCI firmware controller DT node
- ti,sci-dev-id: TI-SCI device identifier as per TI-SCI firmware spec

if both parameters present - Ringacc driver will configure/free/reset Rings
using TI-SCI Message Ringacc RM Protocol.

The Ringacc driver manages Rings allocation by itself now and requests
TI-SCI firmware to allocate and configure specific Rings only. It's done
this way because, Linux driver implements two stage Rings allocation and
configuration (allocate ring and configure ring) while I-SCI Message
Protocol supports only one combined operation (allocate+configure).

Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
 drivers/soc/ti/Kconfig            |   17 +
 drivers/soc/ti/Makefile           |    1 +
 drivers/soc/ti/k3-ringacc.c       | 1191 +++++++++++++++++++++++++++++
 include/linux/soc/ti/k3-ringacc.h |  262 +++++++
 4 files changed, 1471 insertions(+)
 create mode 100644 drivers/soc/ti/k3-ringacc.c
 create mode 100644 include/linux/soc/ti/k3-ringacc.h

Comments

Peter Ujfalusi Aug. 30, 2019, 12:57 p.m. UTC | #1
Hi,

On 30/07/2019 12.34, Peter Ujfalusi wrote:
> From: Grygorii Strashko <grygorii.strashko@ti.com>
> 
> The Ring Accelerator (RINGACC or RA) provides hardware acceleration to
> enable straightforward passing of work between a producer and a consumer.
> There is one RINGACC module per NAVSS on TI AM65x SoCs.
> 
> The RINGACC converts constant-address read and write accesses to equivalent
> read or write accesses to a circular data structure in memory. The RINGACC
> eliminates the need for each DMA controller which needs to access ring
> elements from having to know the current state of the ring (base address,
> current offset). The DMA controller performs a read or write access to a
> specific address range (which maps to the source interface on the RINGACC)
> and the RINGACC replaces the address for the transaction with a new address
> which corresponds to the head or tail element of the ring (head for reads,
> tail for writes). Since the RINGACC maintains the state, multiple DMA
> controllers or channels are allowed to coherently share the same rings as
> applicable. The RINGACC is able to place data which is destined towards
> software into cached memory directly.
> 
> Supported ring modes:
> - Ring Mode
> - Messaging Mode
> - Credentials Mode
> - Queue Manager Mode
> 
> TI-SCI integration:
> 
> Texas Instrument's System Control Interface (TI-SCI) Message Protocol now
> has control over Ringacc module resources management (RM) and Rings
> configuration.
> 
> The corresponding support of TI-SCI Ringacc module RM protocol
> introduced as option through DT parameters:
> - ti,sci: phandle on TI-SCI firmware controller DT node
> - ti,sci-dev-id: TI-SCI device identifier as per TI-SCI firmware spec
> 
> if both parameters present - Ringacc driver will configure/free/reset Rings
> using TI-SCI Message Ringacc RM Protocol.
> 
> The Ringacc driver manages Rings allocation by itself now and requests
> TI-SCI firmware to allocate and configure specific Rings only. It's done
> this way because, Linux driver implements two stage Rings allocation and
> configuration (allocate ring and configure ring) while I-SCI Message
> Protocol supports only one combined operation (allocate+configure).
> 
> Grygorii Strashko <grygorii.strashko@ti.com>
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
> ---
>  drivers/soc/ti/Kconfig            |   17 +
>  drivers/soc/ti/Makefile           |    1 +
>  drivers/soc/ti/k3-ringacc.c       | 1191 +++++++++++++++++++++++++++++
>  include/linux/soc/ti/k3-ringacc.h |  262 +++++++
>  4 files changed, 1471 insertions(+)
>  create mode 100644 drivers/soc/ti/k3-ringacc.c
>  create mode 100644 include/linux/soc/ti/k3-ringacc.h
> 
> diff --git a/drivers/soc/ti/Kconfig b/drivers/soc/ti/Kconfig
> index cf545f428d03..10c76faa503e 100644
> --- a/drivers/soc/ti/Kconfig
> +++ b/drivers/soc/ti/Kconfig
> @@ -80,6 +80,23 @@ config TI_SCI_PM_DOMAINS
>  	  called ti_sci_pm_domains. Note this is needed early in boot before
>  	  rootfs may be available.
>  
> +config TI_K3_RINGACC
> +	tristate "K3 Ring accelerator Sub System"
> +	depends on ARCH_K3 || COMPILE_TEST
> +	depends on TI_SCI_INTA_IRQCHIP
> +	default y
> +	help
> +	  Say y here to support the K3 Ring accelerator module.
> +	  The Ring Accelerator (RINGACC or RA)  provides hardware acceleration
> +	  to enable straightforward passing of work between a producer
> +	  and a consumer. There is one RINGACC module per NAVSS on TI AM65x SoCs
> +	  If unsure, say N.
> +
> +config TI_K3_RINGACC_DEBUG
> +	tristate "K3 Ring accelerator Sub System tests and debug"
> +	depends on TI_K3_RINGACC
> +	default n
> +
>  endif # SOC_TI
>  
>  config TI_SCI_INTA_MSI_DOMAIN
> diff --git a/drivers/soc/ti/Makefile b/drivers/soc/ti/Makefile
> index b3868d392d4f..cc4bc8b08bf5 100644
> --- a/drivers/soc/ti/Makefile
> +++ b/drivers/soc/ti/Makefile
> @@ -9,3 +9,4 @@ obj-$(CONFIG_AMX3_PM)			+= pm33xx.o
>  obj-$(CONFIG_WKUP_M3_IPC)		+= wkup_m3_ipc.o
>  obj-$(CONFIG_TI_SCI_PM_DOMAINS)		+= ti_sci_pm_domains.o
>  obj-$(CONFIG_TI_SCI_INTA_MSI_DOMAIN)	+= ti_sci_inta_msi.o
> +obj-$(CONFIG_TI_K3_RINGACC)		+= k3-ringacc.o
> diff --git a/drivers/soc/ti/k3-ringacc.c b/drivers/soc/ti/k3-ringacc.c
> new file mode 100644
> index 000000000000..401dfc963319
> --- /dev/null
> +++ b/drivers/soc/ti/k3-ringacc.c
> @@ -0,0 +1,1191 @@

...

> +void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ)
> +{
> +	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
> +		return;
> +
> +	if (!ring->parent->dma_ring_reset_quirk)

k3_ringacc_ring_reset(ring); is missing from here.

> +		return;
> +
> +	if (!occ)
> +		occ = dbg_readl(&ring->rt->occ);
> +
> +	if (occ) {
> +		u32 db_ring_cnt, db_ring_cnt_cur;
> +
> +		k3_nav_dbg(ring->parent->dev, "%s %u occ: %u\n", __func__,
> +			   ring->ring_id, occ);
> +		/* 2. Reset the ring */
> +		k3_ringacc_ring_reset_sci(ring);
> +
> +		/*
> +		 * 3. Setup the ring in ring/doorbell mode
> +		 * (if not already in this mode)
> +		 */
> +		if (ring->mode != K3_RINGACC_RING_MODE_RING)
> +			k3_ringacc_ring_reconfig_qmode_sci(
> +					ring, K3_RINGACC_RING_MODE_RING);
> +		/*
> +		 * 4. Ring the doorbell 2**22 – ringOcc times.
> +		 * This will wrap the internal UDMAP ring state occupancy
> +		 * counter (which is 21-bits wide) to 0.
> +		 */
> +		db_ring_cnt = (1U << 22) - occ;
> +
> +		while (db_ring_cnt != 0) {
> +			/*
> +			 * Ring the doorbell with the maximum count each
> +			 * iteration if possible to minimize the total
> +			 * of writes
> +			 */
> +			if (db_ring_cnt > K3_RINGACC_MAX_DB_RING_CNT)
> +				db_ring_cnt_cur = K3_RINGACC_MAX_DB_RING_CNT;
> +			else
> +				db_ring_cnt_cur = db_ring_cnt;
> +
> +			writel(db_ring_cnt_cur, &ring->rt->db);
> +			db_ring_cnt -= db_ring_cnt_cur;
> +		}
> +
> +		/* 5. Restore the original ring mode (if not ring mode) */
> +		if (ring->mode != K3_RINGACC_RING_MODE_RING)
> +			k3_ringacc_ring_reconfig_qmode_sci(ring, ring->mode);
> +	}
> +
> +	/* 2. Reset the ring */
> +	k3_ringacc_ring_reset(ring);
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset_dma);

- Péter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
Tero Kristo Sept. 9, 2019, 6:09 a.m. UTC | #2
Hi,

Mostly some cosmetic comments below, other than that seems fine to me.

On 30/07/2019 12:34, Peter Ujfalusi wrote:
> From: Grygorii Strashko <grygorii.strashko@ti.com>
> 
> The Ring Accelerator (RINGACC or RA) provides hardware acceleration to
> enable straightforward passing of work between a producer and a consumer.
> There is one RINGACC module per NAVSS on TI AM65x SoCs.
> 
> The RINGACC converts constant-address read and write accesses to equivalent
> read or write accesses to a circular data structure in memory. The RINGACC
> eliminates the need for each DMA controller which needs to access ring
> elements from having to know the current state of the ring (base address,
> current offset). The DMA controller performs a read or write access to a
> specific address range (which maps to the source interface on the RINGACC)
> and the RINGACC replaces the address for the transaction with a new address
> which corresponds to the head or tail element of the ring (head for reads,
> tail for writes). Since the RINGACC maintains the state, multiple DMA
> controllers or channels are allowed to coherently share the same rings as
> applicable. The RINGACC is able to place data which is destined towards
> software into cached memory directly.
> 
> Supported ring modes:
> - Ring Mode
> - Messaging Mode
> - Credentials Mode
> - Queue Manager Mode
> 
> TI-SCI integration:
> 
> Texas Instrument's System Control Interface (TI-SCI) Message Protocol now
> has control over Ringacc module resources management (RM) and Rings
> configuration.
> 
> The corresponding support of TI-SCI Ringacc module RM protocol
> introduced as option through DT parameters:
> - ti,sci: phandle on TI-SCI firmware controller DT node
> - ti,sci-dev-id: TI-SCI device identifier as per TI-SCI firmware spec
> 
> if both parameters present - Ringacc driver will configure/free/reset Rings
> using TI-SCI Message Ringacc RM Protocol.
> 
> The Ringacc driver manages Rings allocation by itself now and requests
> TI-SCI firmware to allocate and configure specific Rings only. It's done
> this way because, Linux driver implements two stage Rings allocation and
> configuration (allocate ring and configure ring) while I-SCI Message

I-SCI should be TI-SCI I believe.

> Protocol supports only one combined operation (allocate+configure).
> 
> Grygorii Strashko <grygorii.strashko@ti.com>

Above seems to be missing SoB?

> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
> ---
>   drivers/soc/ti/Kconfig            |   17 +
>   drivers/soc/ti/Makefile           |    1 +
>   drivers/soc/ti/k3-ringacc.c       | 1191 +++++++++++++++++++++++++++++
>   include/linux/soc/ti/k3-ringacc.h |  262 +++++++
>   4 files changed, 1471 insertions(+)
>   create mode 100644 drivers/soc/ti/k3-ringacc.c
>   create mode 100644 include/linux/soc/ti/k3-ringacc.h
> 
> diff --git a/drivers/soc/ti/Kconfig b/drivers/soc/ti/Kconfig
> index cf545f428d03..10c76faa503e 100644
> --- a/drivers/soc/ti/Kconfig
> +++ b/drivers/soc/ti/Kconfig
> @@ -80,6 +80,23 @@ config TI_SCI_PM_DOMAINS
>   	  called ti_sci_pm_domains. Note this is needed early in boot before
>   	  rootfs may be available.
>   
> +config TI_K3_RINGACC
> +	tristate "K3 Ring accelerator Sub System"
> +	depends on ARCH_K3 || COMPILE_TEST
> +	depends on TI_SCI_INTA_IRQCHIP
> +	default y
> +	help
> +	  Say y here to support the K3 Ring accelerator module.
> +	  The Ring Accelerator (RINGACC or RA)  provides hardware acceleration
> +	  to enable straightforward passing of work between a producer
> +	  and a consumer. There is one RINGACC module per NAVSS on TI AM65x SoCs
> +	  If unsure, say N.
> +
> +config TI_K3_RINGACC_DEBUG
> +	tristate "K3 Ring accelerator Sub System tests and debug"
> +	depends on TI_K3_RINGACC
> +	default n
> +
>   endif # SOC_TI
>   
>   config TI_SCI_INTA_MSI_DOMAIN
> diff --git a/drivers/soc/ti/Makefile b/drivers/soc/ti/Makefile
> index b3868d392d4f..cc4bc8b08bf5 100644
> --- a/drivers/soc/ti/Makefile
> +++ b/drivers/soc/ti/Makefile
> @@ -9,3 +9,4 @@ obj-$(CONFIG_AMX3_PM)			+= pm33xx.o
>   obj-$(CONFIG_WKUP_M3_IPC)		+= wkup_m3_ipc.o
>   obj-$(CONFIG_TI_SCI_PM_DOMAINS)		+= ti_sci_pm_domains.o
>   obj-$(CONFIG_TI_SCI_INTA_MSI_DOMAIN)	+= ti_sci_inta_msi.o
> +obj-$(CONFIG_TI_K3_RINGACC)		+= k3-ringacc.o
> diff --git a/drivers/soc/ti/k3-ringacc.c b/drivers/soc/ti/k3-ringacc.c
> new file mode 100644
> index 000000000000..401dfc963319
> --- /dev/null
> +++ b/drivers/soc/ti/k3-ringacc.c
> @@ -0,0 +1,1191 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * TI K3 NAVSS Ring Accelerator subsystem driver
> + *
> + * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
> + */
> +
> +#include <linux/dma-mapping.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/soc/ti/k3-ringacc.h>
> +#include <linux/soc/ti/ti_sci_protocol.h>
> +#include <linux/soc/ti/ti_sci_inta_msi.h>
> +#include <linux/of_irq.h>
> +#include <linux/irqdomain.h>
> +
> +static LIST_HEAD(k3_ringacc_list);
> +static DEFINE_MUTEX(k3_ringacc_list_lock);
> +
> +#ifdef CONFIG_TI_K3_RINGACC_DEBUG
> +#define	k3_nav_dbg(dev, arg...) dev_err(dev, arg)

dev_err seems exaggeration for debug purposes, maybe just dev_info.

> +static	void dbg_writel(u32 v, void __iomem *reg)
> +{
> +	pr_err("WRITEL(32): v(%08X)-->reg(%p)\n", v, reg);

Again, maybe just pr_info.

> +	writel(v, reg);
> +}
> +
> +static	u32 dbg_readl(void __iomem *reg)
> +{
> +	u32 v;
> +
> +	v = readl(reg);
> +	pr_err("READL(32): v(%08X)<--reg(%p)\n", v, reg);
> +	return v;
> +}
> +#else
> +#define	k3_nav_dbg(dev, arg...) dev_dbg(dev, arg)
> +#define dbg_writel(v, reg) writel(v, reg)

Do you need to use hard writel, writel_relaxed is not enough?

> +
> +#define dbg_readl(reg) readl(reg)

Same as above but for read?

> +#endif
> +
> +#define K3_RINGACC_CFG_RING_SIZE_ELCNT_MASK		GENMASK(19, 0)
> +
> +/**
> + * struct k3_ring_rt_regs -  The RA Control/Status Registers region
> + */
> +struct k3_ring_rt_regs {
> +	u32	resv_16[4];
> +	u32	db;		/* RT Ring N Doorbell Register */
> +	u32	resv_4[1];
> +	u32	occ;		/* RT Ring N Occupancy Register */
> +	u32	indx;		/* RT Ring N Current Index Register */
> +	u32	hwocc;		/* RT Ring N Hardware Occupancy Register */
> +	u32	hwindx;		/* RT Ring N Current Index Register */
> +};
> +
> +#define K3_RINGACC_RT_REGS_STEP	0x1000
> +
> +/**
> + * struct k3_ring_fifo_regs -  The Ring Accelerator Queues Registers region
> + */
> +struct k3_ring_fifo_regs {
> +	u32	head_data[128];		/* Ring Head Entry Data Registers */
> +	u32	tail_data[128];		/* Ring Tail Entry Data Registers */
> +	u32	peek_head_data[128];	/* Ring Peek Head Entry Data Regs */
> +	u32	peek_tail_data[128];	/* Ring Peek Tail Entry Data Regs */
> +};
> +
> +/**
> + * struct k3_ringacc_proxy_gcfg_regs - RA Proxy Global Config MMIO Region
> + */
> +struct k3_ringacc_proxy_gcfg_regs {
> +	u32	revision;	/* Revision Register */
> +	u32	config;		/* Config Register */
> +};
> +
> +#define K3_RINGACC_PROXY_CFG_THREADS_MASK		GENMASK(15, 0)
> +
> +/**
> + * struct k3_ringacc_proxy_target_regs -  Proxy Datapath MMIO Region
> + */
> +struct k3_ringacc_proxy_target_regs {
> +	u32	control;	/* Proxy Control Register */
> +	u32	status;		/* Proxy Status Register */
> +	u8	resv_512[504];
> +	u32	data[128];	/* Proxy Data Register */
> +};
> +
> +#define K3_RINGACC_PROXY_TARGET_STEP	0x1000
> +#define K3_RINGACC_PROXY_NOT_USED	(-1)
> +
> +enum k3_ringacc_proxy_access_mode {
> +	PROXY_ACCESS_MODE_HEAD = 0,
> +	PROXY_ACCESS_MODE_TAIL = 1,
> +	PROXY_ACCESS_MODE_PEEK_HEAD = 2,
> +	PROXY_ACCESS_MODE_PEEK_TAIL = 3,
> +};
> +
> +#define K3_RINGACC_FIFO_WINDOW_SIZE_BYTES  (512U)
> +#define K3_RINGACC_FIFO_REGS_STEP	0x1000
> +#define K3_RINGACC_MAX_DB_RING_CNT    (127U)
> +
> +/**
> + * struct k3_ring_ops -  Ring operations
> + */
> +struct k3_ring_ops {
> +	int (*push_tail)(struct k3_ring *ring, void *elm);
> +	int (*push_head)(struct k3_ring *ring, void *elm);
> +	int (*pop_tail)(struct k3_ring *ring, void *elm);
> +	int (*pop_head)(struct k3_ring *ring, void *elm);
> +};
> +
> +/**
> + * struct k3_ring - RA Ring descriptor
> + *
> + * @rt - Ring control/status registers
> + * @fifos - Ring queues registers
> + * @proxy - Ring Proxy Datapath registers
> + * @ring_mem_dma - Ring buffer dma address
> + * @ring_mem_virt - Ring buffer virt address
> + * @ops - Ring operations
> + * @size - Ring size in elements
> + * @elm_size - Size of the ring element
> + * @mode - Ring mode
> + * @flags - flags
> + * @free - Number of free elements
> + * @occ - Ring occupancy
> + * @windex - Write index (only for @K3_RINGACC_RING_MODE_RING)
> + * @rindex - Read index (only for @K3_RINGACC_RING_MODE_RING)
> + * @ring_id - Ring Id
> + * @parent - Pointer on struct @k3_ringacc
> + * @use_count - Use count for shared rings
> + * @proxy_id - RA Ring Proxy Id (only if @K3_RINGACC_RING_USE_PROXY)
> + */
> +struct k3_ring {
> +	struct k3_ring_rt_regs __iomem *rt;
> +	struct k3_ring_fifo_regs __iomem *fifos;
> +	struct k3_ringacc_proxy_target_regs  __iomem *proxy;
> +	dma_addr_t	ring_mem_dma;
> +	void		*ring_mem_virt;
> +	struct k3_ring_ops *ops;
> +	u32		size;
> +	enum k3_ring_size elm_size;
> +	enum k3_ring_mode mode;
> +	u32		flags;
> +#define K3_RING_FLAG_BUSY	BIT(1)
> +#define K3_RING_FLAG_SHARED	BIT(2)
> +	u32		free;
> +	u32		occ;
> +	u32		windex;
> +	u32		rindex;
> +	u32		ring_id;
> +	struct k3_ringacc	*parent;
> +	u32		use_count;
> +	int		proxy_id;
> +};
> +
> +/**
> + * struct k3_ringacc - Rings accelerator descriptor
> + *
> + * @dev - pointer on RA device
> + * @proxy_gcfg - RA proxy global config registers
> + * @proxy_target_base - RA proxy datapath region
> + * @num_rings - number of ring in RA
> + * @rm_gp_range - general purpose rings range from tisci
> + * @dma_ring_reset_quirk - DMA reset w/a enable
> + * @num_proxies - number of RA proxies
> + * @rings - array of rings descriptors (struct @k3_ring)
> + * @list - list of RAs in the system
> + * @tisci - pointer ti-sci handle
> + * @tisci_ring_ops - ti-sci rings ops
> + * @tisci_dev_id - ti-sci device id
> + */
> +struct k3_ringacc {
> +	struct device *dev;
> +	struct k3_ringacc_proxy_gcfg_regs __iomem *proxy_gcfg;
> +	void __iomem *proxy_target_base;
> +	u32 num_rings; /* number of rings in Ringacc module */
> +	unsigned long *rings_inuse;
> +	struct ti_sci_resource *rm_gp_range;
> +
> +	bool dma_ring_reset_quirk;
> +	u32 num_proxies;
> +	unsigned long *proxy_inuse;

proxy_inuse is not documented above.

> +
> +	struct k3_ring *rings;
> +	struct list_head list;
> +	struct mutex req_lock; /* protect rings allocation */
> +
> +	const struct ti_sci_handle *tisci;
> +	const struct ti_sci_rm_ringacc_ops *tisci_ring_ops;
> +	u32  tisci_dev_id;
> +};
> +
> +static long k3_ringacc_ring_get_fifo_pos(struct k3_ring *ring)
> +{
> +	return K3_RINGACC_FIFO_WINDOW_SIZE_BYTES -
> +	       (4 << ring->elm_size);
> +}
> +
> +static void *k3_ringacc_get_elm_addr(struct k3_ring *ring, u32 idx)
> +{
> +	return (idx * (4 << ring->elm_size) + ring->ring_mem_virt);

The arithmetic here seems backwards compared to most other code I've 
seen. It would be more readable if you have it like:

ring->ring_mem_virt + idx * (4 << ring->elm_size);

> +}
> +
> +static int k3_ringacc_ring_push_mem(struct k3_ring *ring, void *elem);
> +static int k3_ringacc_ring_pop_mem(struct k3_ring *ring, void *elem);
> +
> +static struct k3_ring_ops k3_ring_mode_ring_ops = {
> +		.push_tail = k3_ringacc_ring_push_mem,
> +		.pop_head = k3_ringacc_ring_pop_mem,
> +};
> +
> +static int k3_ringacc_ring_push_io(struct k3_ring *ring, void *elem);
> +static int k3_ringacc_ring_pop_io(struct k3_ring *ring, void *elem);
> +static int k3_ringacc_ring_push_head_io(struct k3_ring *ring, void *elem);
> +static int k3_ringacc_ring_pop_tail_io(struct k3_ring *ring, void *elem);
> +
> +static struct k3_ring_ops k3_ring_mode_msg_ops = {
> +		.push_tail = k3_ringacc_ring_push_io,
> +		.push_head = k3_ringacc_ring_push_head_io,
> +		.pop_tail = k3_ringacc_ring_pop_tail_io,
> +		.pop_head = k3_ringacc_ring_pop_io,
> +};
> +
> +static int k3_ringacc_ring_push_head_proxy(struct k3_ring *ring, void *elem);
> +static int k3_ringacc_ring_push_tail_proxy(struct k3_ring *ring, void *elem);
> +static int k3_ringacc_ring_pop_head_proxy(struct k3_ring *ring, void *elem);
> +static int k3_ringacc_ring_pop_tail_proxy(struct k3_ring *ring, void *elem);
> +
> +static struct k3_ring_ops k3_ring_mode_proxy_ops = {
> +		.push_tail = k3_ringacc_ring_push_tail_proxy,
> +		.push_head = k3_ringacc_ring_push_head_proxy,
> +		.pop_tail = k3_ringacc_ring_pop_tail_proxy,
> +		.pop_head = k3_ringacc_ring_pop_head_proxy,
> +};
> +
> +#ifdef CONFIG_TI_K3_RINGACC_DEBUG
> +void k3_ringacc_ring_dump(struct k3_ring *ring)
> +{
> +	struct device *dev = ring->parent->dev;
> +
> +	k3_nav_dbg(dev, "dump ring: %d\n", ring->ring_id);
> +	k3_nav_dbg(dev, "dump mem virt %p, dma %pad\n",
> +		   ring->ring_mem_virt, &ring->ring_mem_dma);
> +	k3_nav_dbg(dev, "dump elmsize %d, size %d, mode %d, proxy_id %d\n",
> +		   ring->elm_size, ring->size, ring->mode, ring->proxy_id);
> +
> +	k3_nav_dbg(dev, "dump ring_rt_regs: db%08x\n",
> +		   readl(&ring->rt->db));

Why not use readl_relaxed in this func?

> +	k3_nav_dbg(dev, "dump occ%08x\n",
> +		   readl(&ring->rt->occ));
> +	k3_nav_dbg(dev, "dump indx%08x\n",
> +		   readl(&ring->rt->indx));
> +	k3_nav_dbg(dev, "dump hwocc%08x\n",
> +		   readl(&ring->rt->hwocc));
> +	k3_nav_dbg(dev, "dump hwindx%08x\n",
> +		   readl(&ring->rt->hwindx));
> +
> +	if (ring->ring_mem_virt)
> +		print_hex_dump(KERN_ERR, "dump ring_mem_virt ",
> +			       DUMP_PREFIX_NONE, 16, 1,
> +			       ring->ring_mem_virt, 16 * 8, false);
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_dump);

Do you really need to export a debug function?

> +#endif
> +
> +struct k3_ring *k3_ringacc_request_ring(struct k3_ringacc *ringacc,
> +					int id, u32 flags)
> +{
> +	int proxy_id = K3_RINGACC_PROXY_NOT_USED;
> +
> +	mutex_lock(&ringacc->req_lock);
> +
> +	if (id == K3_RINGACC_RING_ID_ANY) {
> +		/* Request for any general purpose ring */
> +		struct ti_sci_resource_desc *gp_rings =
> +						&ringacc->rm_gp_range->desc[0];
> +		unsigned long size;
> +
> +		size = gp_rings->start + gp_rings->num;
> +		id = find_next_zero_bit(ringacc->rings_inuse, size,
> +					gp_rings->start);
> +		if (id == size)
> +			goto error;
> +	} else if (id < 0) {
> +		goto error;
> +	}
> +
> +	if (test_bit(id, ringacc->rings_inuse) &&
> +	    !(ringacc->rings[id].flags & K3_RING_FLAG_SHARED))
> +		goto error;
> +	else if (ringacc->rings[id].flags & K3_RING_FLAG_SHARED)
> +		goto out;
> +
> +	if (flags & K3_RINGACC_RING_USE_PROXY) {
> +		proxy_id = find_next_zero_bit(ringacc->proxy_inuse,
> +					      ringacc->num_proxies, 0);
> +		if (proxy_id == ringacc->num_proxies)
> +			goto error;
> +	}
> +
> +	if (!try_module_get(ringacc->dev->driver->owner))
> +		goto error;
> +
> +	if (proxy_id != K3_RINGACC_PROXY_NOT_USED) {
> +		set_bit(proxy_id, ringacc->proxy_inuse);
> +		ringacc->rings[id].proxy_id = proxy_id;
> +		k3_nav_dbg(ringacc->dev, "Giving ring#%d proxy#%d\n",
> +			   id, proxy_id);
> +	} else {
> +		k3_nav_dbg(ringacc->dev, "Giving ring#%d\n", id);
> +	}
> +
> +	set_bit(id, ringacc->rings_inuse);
> +out:
> +	ringacc->rings[id].use_count++;
> +	mutex_unlock(&ringacc->req_lock);
> +	return &ringacc->rings[id];
> +
> +error:
> +	mutex_unlock(&ringacc->req_lock);
> +	return NULL;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_request_ring);
> +
> +static void k3_ringacc_ring_reset_sci(struct k3_ring *ring)
> +{
> +	struct k3_ringacc *ringacc = ring->parent;
> +	int ret;
> +
> +	ret = ringacc->tisci_ring_ops->config(
> +			ringacc->tisci,
> +			TI_SCI_MSG_VALUE_RM_RING_COUNT_VALID,
> +			ringacc->tisci_dev_id,
> +			ring->ring_id,
> +			0,
> +			0,
> +			ring->size,
> +			0,
> +			0,
> +			0);
> +	if (ret)
> +		dev_err(ringacc->dev, "TISCI reset ring fail (%d) ring_idx %d\n",
> +			ret, ring->ring_id);

Return value of sci ops is masked, why not return it and let the caller 
handle it properly?

Same comment for anything similar that follows.

> +}
> +
> +void k3_ringacc_ring_reset(struct k3_ring *ring)
> +{
> +	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
> +		return;
> +
> +	ring->occ = 0;
> +	ring->free = 0;
> +	ring->rindex = 0;
> +	ring->windex = 0;
> +
> +	k3_ringacc_ring_reset_sci(ring);
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset);
> +
> +static void k3_ringacc_ring_reconfig_qmode_sci(struct k3_ring *ring,
> +					       enum k3_ring_mode mode)
> +{
> +	struct k3_ringacc *ringacc = ring->parent;
> +	int ret;
> +
> +	ret = ringacc->tisci_ring_ops->config(
> +			ringacc->tisci,
> +			TI_SCI_MSG_VALUE_RM_RING_MODE_VALID,
> +			ringacc->tisci_dev_id,
> +			ring->ring_id,
> +			0,
> +			0,
> +			0,
> +			mode,
> +			0,
> +			0);
> +	if (ret)
> +		dev_err(ringacc->dev, "TISCI reconf qmode fail (%d) ring_idx %d\n",
> +			ret, ring->ring_id);
>+}
> +
> +void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ)
> +{
> +	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
> +		return;
> +
> +	if (!ring->parent->dma_ring_reset_quirk)
> +		return;
> +
> +	if (!occ)
> +		occ = dbg_readl(&ring->rt->occ);
> +
> +	if (occ) {
> +		u32 db_ring_cnt, db_ring_cnt_cur;
> +
> +		k3_nav_dbg(ring->parent->dev, "%s %u occ: %u\n", __func__,
> +			   ring->ring_id, occ);
> +		/* 2. Reset the ring */

2? Where is 1?

> +		k3_ringacc_ring_reset_sci(ring);
> +
> +		/*
> +		 * 3. Setup the ring in ring/doorbell mode
> +		 * (if not already in this mode)
> +		 */
> +		if (ring->mode != K3_RINGACC_RING_MODE_RING)
> +			k3_ringacc_ring_reconfig_qmode_sci(
> +					ring, K3_RINGACC_RING_MODE_RING);
> +		/*
> +		 * 4. Ring the doorbell 2**22 – ringOcc times.
> +		 * This will wrap the internal UDMAP ring state occupancy
> +		 * counter (which is 21-bits wide) to 0.
> +		 */
> +		db_ring_cnt = (1U << 22) - occ;
> +
> +		while (db_ring_cnt != 0) {
> +			/*
> +			 * Ring the doorbell with the maximum count each
> +			 * iteration if possible to minimize the total
> +			 * of writes
> +			 */
> +			if (db_ring_cnt > K3_RINGACC_MAX_DB_RING_CNT)
> +				db_ring_cnt_cur = K3_RINGACC_MAX_DB_RING_CNT;
> +			else
> +				db_ring_cnt_cur = db_ring_cnt;
> +
> +			writel(db_ring_cnt_cur, &ring->rt->db);
> +			db_ring_cnt -= db_ring_cnt_cur;
> +		}
> +
> +		/* 5. Restore the original ring mode (if not ring mode) */
> +		if (ring->mode != K3_RINGACC_RING_MODE_RING)
> +			k3_ringacc_ring_reconfig_qmode_sci(ring, ring->mode);
> +	}
> +
> +	/* 2. Reset the ring */

Again 2?

> +	k3_ringacc_ring_reset(ring);
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset_dma);
> +
> +static void k3_ringacc_ring_free_sci(struct k3_ring *ring)
> +{
> +	struct k3_ringacc *ringacc = ring->parent;
> +	int ret;
> +
> +	ret = ringacc->tisci_ring_ops->config(
> +			ringacc->tisci,
> +			TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
> +			ringacc->tisci_dev_id,
> +			ring->ring_id,
> +			0,
> +			0,
> +			0,
> +			0,
> +			0,
> +			0);
> +	if (ret)
> +		dev_err(ringacc->dev, "TISCI ring free fail (%d) ring_idx %d\n",
> +			ret, ring->ring_id);
> +}
> +
> +int k3_ringacc_ring_free(struct k3_ring *ring)
> +{
> +	struct k3_ringacc *ringacc;
> +
> +	if (!ring)
> +		return -EINVAL;
> +
> +	ringacc = ring->parent;
> +
> +	k3_nav_dbg(ring->parent->dev, "flags: 0x%08x\n", ring->flags);
> +
> +	if (!test_bit(ring->ring_id, ringacc->rings_inuse))
> +		return -EINVAL;
> +
> +	mutex_lock(&ringacc->req_lock);
> +
> +	if (--ring->use_count)
> +		goto out;
> +
> +	if (!(ring->flags & K3_RING_FLAG_BUSY))
> +		goto no_init;
> +
> +	k3_ringacc_ring_free_sci(ring);
> +
> +	dma_free_coherent(ringacc->dev,
> +			  ring->size * (4 << ring->elm_size),
> +			  ring->ring_mem_virt, ring->ring_mem_dma);
> +	ring->flags = 0;
> +	ring->ops = NULL;
> +	if (ring->proxy_id != K3_RINGACC_PROXY_NOT_USED) {
> +		clear_bit(ring->proxy_id, ringacc->proxy_inuse);
> +		ring->proxy = NULL;
> +		ring->proxy_id = K3_RINGACC_PROXY_NOT_USED;
> +	}
> +
> +no_init:
> +	clear_bit(ring->ring_id, ringacc->rings_inuse);
> +
> +	module_put(ringacc->dev->driver->owner);
> +
> +out:
> +	mutex_unlock(&ringacc->req_lock);
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_free);
> +
> +u32 k3_ringacc_get_ring_id(struct k3_ring *ring)
> +{
> +	if (!ring)
> +		return -EINVAL;
> +
> +	return ring->ring_id;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_id);
> +
> +u32 k3_ringacc_get_tisci_dev_id(struct k3_ring *ring)
> +{
> +	if (!ring)
> +		return -EINVAL;
> +

What if parent is NULL? Can it ever be here?

> +	return ring->parent->tisci_dev_id;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_get_tisci_dev_id);
> +
> +int k3_ringacc_get_ring_irq_num(struct k3_ring *ring)
> +{
> +	int irq_num;
> +
> +	if (!ring)
> +		return -EINVAL;
> +
> +	irq_num = ti_sci_inta_msi_get_virq(ring->parent->dev, ring->ring_id);
> +	if (irq_num <= 0)
> +		irq_num = -EINVAL;
> +	return irq_num;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_irq_num);
> +
> +static int k3_ringacc_ring_cfg_sci(struct k3_ring *ring)
> +{
> +	struct k3_ringacc *ringacc = ring->parent;
> +	u32 ring_idx;
> +	int ret;
> +
> +	if (!ringacc->tisci)
> +		return -EINVAL;
> +
> +	ring_idx = ring->ring_id;
> +	ret = ringacc->tisci_ring_ops->config(
> +			ringacc->tisci,
> +			TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
> +			ringacc->tisci_dev_id,
> +			ring_idx,
> +			lower_32_bits(ring->ring_mem_dma),
> +			upper_32_bits(ring->ring_mem_dma),
> +			ring->size,
> +			ring->mode,
> +			ring->elm_size,
> +			0);
> +	if (ret)
> +		dev_err(ringacc->dev, "TISCI config ring fail (%d) ring_idx %d\n",
> +			ret, ring_idx);
> +
> +	return ret;
> +}
> +
> +int k3_ringacc_ring_cfg(struct k3_ring *ring, struct k3_ring_cfg *cfg)
> +{
> +	struct k3_ringacc *ringacc = ring->parent;
> +	int ret = 0;
> +
> +	if (!ring || !cfg)
> +		return -EINVAL;
> +	if (cfg->elm_size > K3_RINGACC_RING_ELSIZE_256 ||
> +	    cfg->mode > K3_RINGACC_RING_MODE_QM ||
> +	    cfg->size & ~K3_RINGACC_CFG_RING_SIZE_ELCNT_MASK ||
> +	    !test_bit(ring->ring_id, ringacc->rings_inuse))
> +		return -EINVAL;
> +
> +	if (ring->use_count != 1)

Hmm, isn't this a failure actually?

> +		return 0;
> +
> +	ring->size = cfg->size;
> +	ring->elm_size = cfg->elm_size;
> +	ring->mode = cfg->mode;
> +	ring->occ = 0;
> +	ring->free = 0;
> +	ring->rindex = 0;
> +	ring->windex = 0;
> +
> +	if (ring->proxy_id != K3_RINGACC_PROXY_NOT_USED)
> +		ring->proxy = ringacc->proxy_target_base +
> +			      ring->proxy_id * K3_RINGACC_PROXY_TARGET_STEP;
> +
> +	switch (ring->mode) {
> +	case K3_RINGACC_RING_MODE_RING:
> +		ring->ops = &k3_ring_mode_ring_ops;
> +		break;
> +	case K3_RINGACC_RING_MODE_QM:
> +		/*
> +		 * In Queue mode elm_size can be 8 only and each operation
> +		 * uses 2 element slots
> +		 */
> +		if (cfg->elm_size != K3_RINGACC_RING_ELSIZE_8 ||
> +		    cfg->size % 2)
> +			goto err_free_proxy;
> +		/* else, fall through */
> +	case K3_RINGACC_RING_MODE_MESSAGE:
> +		if (ring->proxy)
> +			ring->ops = &k3_ring_mode_proxy_ops;
> +		else
> +			ring->ops = &k3_ring_mode_msg_ops;
> +		break;
> +	default:
> +		ring->ops = NULL;
> +		ret = -EINVAL;
> +		goto err_free_proxy;
> +	};
> +
> +	ring->ring_mem_virt =
> +			dma_alloc_coherent(ringacc->dev,
> +					   ring->size * (4 << ring->elm_size),
> +					   &ring->ring_mem_dma, GFP_KERNEL);
> +	if (!ring->ring_mem_virt) {
> +		dev_err(ringacc->dev, "Failed to alloc ring mem\n");
> +		ret = -ENOMEM;
> +		goto err_free_ops;
> +	}
> +
> +	ret = k3_ringacc_ring_cfg_sci(ring);
> +
> +	if (ret)
> +		goto err_free_mem;
> +
> +	ring->flags |= K3_RING_FLAG_BUSY;
> +	ring->flags |= (cfg->flags & K3_RINGACC_RING_SHARED) ?
> +			K3_RING_FLAG_SHARED : 0;
> +
> +	k3_ringacc_ring_dump(ring);
> +
> +	return 0;
> +
> +err_free_mem:
> +	dma_free_coherent(ringacc->dev,
> +			  ring->size * (4 << ring->elm_size),
> +			  ring->ring_mem_virt,
> +			  ring->ring_mem_dma);
> +err_free_ops:
> +	ring->ops = NULL;
> +err_free_proxy:
> +	ring->proxy = NULL;
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_cfg);
> +
> +u32 k3_ringacc_ring_get_size(struct k3_ring *ring)
> +{
> +	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
> +		return -EINVAL;
> +
> +	return ring->size;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_size);
> +
> +u32 k3_ringacc_ring_get_free(struct k3_ring *ring)
> +{
> +	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
> +		return -EINVAL;
> +
> +	if (!ring->free)
> +		ring->free = ring->size - dbg_readl(&ring->rt->occ);
> +
> +	return ring->free;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_free);
> +
> +u32 k3_ringacc_ring_get_occ(struct k3_ring *ring)
> +{
> +	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
> +		return -EINVAL;
> +
> +	return dbg_readl(&ring->rt->occ);
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_occ);
> +
> +u32 k3_ringacc_ring_is_full(struct k3_ring *ring)
> +{
> +	return !k3_ringacc_ring_get_free(ring);
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_is_full);
> +
> +enum k3_ringacc_access_mode {
> +	K3_RINGACC_ACCESS_MODE_PUSH_HEAD,
> +	K3_RINGACC_ACCESS_MODE_POP_HEAD,
> +	K3_RINGACC_ACCESS_MODE_PUSH_TAIL,
> +	K3_RINGACC_ACCESS_MODE_POP_TAIL,
> +	K3_RINGACC_ACCESS_MODE_PEEK_HEAD,
> +	K3_RINGACC_ACCESS_MODE_PEEK_TAIL,
> +};
> +
> +static int k3_ringacc_ring_cfg_proxy(struct k3_ring *ring,
> +				     enum k3_ringacc_proxy_access_mode mode)
> +{
> +	u32 val;
> +
> +	val = ring->ring_id;
> +	val |= mode << 16;
> +	val |= ring->elm_size << 24;

Would be nice to have these magic shifts as defines.

> +	dbg_writel(val, &ring->proxy->control);
> +	return 0;
> +}
> +
> +static int k3_ringacc_ring_access_proxy(struct k3_ring *ring, void *elem,
> +					enum k3_ringacc_access_mode access_mode)
> +{
> +	void __iomem *ptr;
> +
> +	ptr = (void __iomem *)&ring->proxy->data;
> +
> +	switch (access_mode) {
> +	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
> +	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
> +		k3_ringacc_ring_cfg_proxy(ring, PROXY_ACCESS_MODE_HEAD);
> +		break;
> +	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
> +	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
> +		k3_ringacc_ring_cfg_proxy(ring, PROXY_ACCESS_MODE_TAIL);
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	ptr += k3_ringacc_ring_get_fifo_pos(ring);
> +
> +	switch (access_mode) {
> +	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
> +	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
> +		k3_nav_dbg(ring->parent->dev, "proxy:memcpy_fromio(x): --> ptr(%p), mode:%d\n",
> +			   ptr, access_mode);
> +		memcpy_fromio(elem, ptr, (4 << ring->elm_size));
> +		ring->occ--;
> +		break;
> +	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
> +	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
> +		k3_nav_dbg(ring->parent->dev, "proxy:memcpy_toio(x): --> ptr(%p), mode:%d\n",
> +			   ptr, access_mode);
> +		memcpy_toio(ptr, elem, (4 << ring->elm_size));
> +		ring->free--;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	k3_nav_dbg(ring->parent->dev, "proxy: free%d occ%d\n",
> +		   ring->free, ring->occ);
> +	return 0;
> +}
> +
> +static int k3_ringacc_ring_push_head_proxy(struct k3_ring *ring, void *elem)
> +{
> +	return k3_ringacc_ring_access_proxy(ring, elem,
> +					    K3_RINGACC_ACCESS_MODE_PUSH_HEAD);
> +}
> +
> +static int k3_ringacc_ring_push_tail_proxy(struct k3_ring *ring, void *elem)
> +{
> +	return k3_ringacc_ring_access_proxy(ring, elem,
> +					    K3_RINGACC_ACCESS_MODE_PUSH_TAIL);
> +}
> +
> +static int k3_ringacc_ring_pop_head_proxy(struct k3_ring *ring, void *elem)
> +{
> +	return k3_ringacc_ring_access_proxy(ring, elem,
> +					    K3_RINGACC_ACCESS_MODE_POP_HEAD);
> +}
> +
> +static int k3_ringacc_ring_pop_tail_proxy(struct k3_ring *ring, void *elem)
> +{
> +	return k3_ringacc_ring_access_proxy(ring, elem,
> +					    K3_RINGACC_ACCESS_MODE_POP_HEAD);
> +}
> +
> +static int k3_ringacc_ring_access_io(struct k3_ring *ring, void *elem,
> +				     enum k3_ringacc_access_mode access_mode)
> +{
> +	void __iomem *ptr;
> +
> +	switch (access_mode) {
> +	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
> +	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
> +		ptr = (void __iomem *)&ring->fifos->head_data;
> +		break;
> +	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
> +	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
> +		ptr = (void __iomem *)&ring->fifos->tail_data;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	ptr += k3_ringacc_ring_get_fifo_pos(ring);
> +
> +	switch (access_mode) {
> +	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
> +	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
> +		k3_nav_dbg(ring->parent->dev, "memcpy_fromio(x): --> ptr(%p), mode:%d\n",
> +			   ptr, access_mode);
> +		memcpy_fromio(elem, ptr, (4 << ring->elm_size));
> +		ring->occ--;
> +		break;
> +	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
> +	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
> +		k3_nav_dbg(ring->parent->dev, "memcpy_toio(x): --> ptr(%p), mode:%d\n",
> +			   ptr, access_mode);
> +		memcpy_toio(ptr, elem, (4 << ring->elm_size));
> +		ring->free--;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	k3_nav_dbg(ring->parent->dev, "free%d index%d occ%d index%d\n",
> +		   ring->free, ring->windex, ring->occ, ring->rindex);
> +	return 0;
> +}
> +
> +static int k3_ringacc_ring_push_head_io(struct k3_ring *ring, void *elem)
> +{
> +	return k3_ringacc_ring_access_io(ring, elem,
> +					 K3_RINGACC_ACCESS_MODE_PUSH_HEAD);
> +}
> +
> +static int k3_ringacc_ring_push_io(struct k3_ring *ring, void *elem)
> +{
> +	return k3_ringacc_ring_access_io(ring, elem,
> +					 K3_RINGACC_ACCESS_MODE_PUSH_TAIL);
> +}
> +
> +static int k3_ringacc_ring_pop_io(struct k3_ring *ring, void *elem)
> +{
> +	return k3_ringacc_ring_access_io(ring, elem,
> +					 K3_RINGACC_ACCESS_MODE_POP_HEAD);
> +}
> +
> +static int k3_ringacc_ring_pop_tail_io(struct k3_ring *ring, void *elem)
> +{
> +	return k3_ringacc_ring_access_io(ring, elem,
> +					 K3_RINGACC_ACCESS_MODE_POP_HEAD);
> +}
> +
> +static int k3_ringacc_ring_push_mem(struct k3_ring *ring, void *elem)
> +{
> +	void *elem_ptr;
> +
> +	elem_ptr = k3_ringacc_get_elm_addr(ring, ring->windex);
> +
> +	memcpy(elem_ptr, elem, (4 << ring->elm_size));
> +
> +	ring->windex = (ring->windex + 1) % ring->size;
> +	ring->free--;
> +	dbg_writel(1, &ring->rt->db);
> +
> +	k3_nav_dbg(ring->parent->dev, "ring_push_mem: free%d index%d\n",
> +		   ring->free, ring->windex);
> +
> +	return 0;
> +}
> +
> +static int k3_ringacc_ring_pop_mem(struct k3_ring *ring, void *elem)
> +{
> +	void *elem_ptr;
> +
> +	elem_ptr = k3_ringacc_get_elm_addr(ring, ring->rindex);
> +
> +	memcpy(elem, elem_ptr, (4 << ring->elm_size));
> +
> +	ring->rindex = (ring->rindex + 1) % ring->size;
> +	ring->occ--;
> +	dbg_writel(-1, &ring->rt->db);
> +
> +	k3_nav_dbg(ring->parent->dev, "ring_pop_mem: occ%d index%d pos_ptr%p\n",
> +		   ring->occ, ring->rindex, elem_ptr);
> +	return 0;
> +}
> +
> +int k3_ringacc_ring_push(struct k3_ring *ring, void *elem)
> +{
> +	int ret = -EOPNOTSUPP;
> +
> +	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
> +		return -EINVAL;
> +
> +	k3_nav_dbg(ring->parent->dev, "ring_push: free%d index%d\n",
> +		   ring->free, ring->windex);
> +
> +	if (k3_ringacc_ring_is_full(ring))
> +		return -ENOMEM;
> +
> +	if (ring->ops && ring->ops->push_tail)
> +		ret = ring->ops->push_tail(ring, elem);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_push);
> +
> +int k3_ringacc_ring_push_head(struct k3_ring *ring, void *elem)
> +{
> +	int ret = -EOPNOTSUPP;
> +
> +	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
> +		return -EINVAL;
> +
> +	k3_nav_dbg(ring->parent->dev, "ring_push_head: free%d index%d\n",
> +		   ring->free, ring->windex);
> +
> +	if (k3_ringacc_ring_is_full(ring))
> +		return -ENOMEM;
> +
> +	if (ring->ops && ring->ops->push_head)
> +		ret = ring->ops->push_head(ring, elem);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_push_head);
> +
> +int k3_ringacc_ring_pop(struct k3_ring *ring, void *elem)
> +{
> +	int ret = -EOPNOTSUPP;
> +
> +	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
> +		return -EINVAL;
> +
> +	if (!ring->occ)
> +		ring->occ = k3_ringacc_ring_get_occ(ring);
> +
> +	k3_nav_dbg(ring->parent->dev, "ring_pop: occ%d index%d\n",
> +		   ring->occ, ring->rindex);
> +
> +	if (!ring->occ)
> +		return -ENODATA;
> +
> +	if (ring->ops && ring->ops->pop_head)
> +		ret = ring->ops->pop_head(ring, elem);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_pop);
> +
> +int k3_ringacc_ring_pop_tail(struct k3_ring *ring, void *elem)
> +{
> +	int ret = -EOPNOTSUPP;
> +
> +	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
> +		return -EINVAL;
> +
> +	if (!ring->occ)
> +		ring->occ = k3_ringacc_ring_get_occ(ring);
> +
> +	k3_nav_dbg(ring->parent->dev, "ring_pop_tail: occ%d index%d\n",
> +		   ring->occ, ring->rindex);
> +
> +	if (!ring->occ)
> +		return -ENODATA;
> +
> +	if (ring->ops && ring->ops->pop_tail)
> +		ret = ring->ops->pop_tail(ring, elem);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_pop_tail);
> +
> +struct k3_ringacc *of_k3_ringacc_get_by_phandle(struct device_node *np,
> +						const char *property)
> +{
> +	struct device_node *ringacc_np;
> +	struct k3_ringacc *ringacc = ERR_PTR(-EPROBE_DEFER);
> +	struct k3_ringacc *entry;
> +
> +	ringacc_np = of_parse_phandle(np, property, 0);
> +	if (!ringacc_np)
> +		return ERR_PTR(-ENODEV);
> +
> +	mutex_lock(&k3_ringacc_list_lock);
> +	list_for_each_entry(entry, &k3_ringacc_list, list)
> +		if (entry->dev->of_node == ringacc_np) {
> +			ringacc = entry;
> +			break;
> +		}
> +	mutex_unlock(&k3_ringacc_list_lock);
> +	of_node_put(ringacc_np);
> +
> +	return ringacc;
> +}
> +EXPORT_SYMBOL_GPL(of_k3_ringacc_get_by_phandle);
> +
> +static int k3_ringacc_probe_dt(struct k3_ringacc *ringacc)
> +{
> +	struct device_node *node = ringacc->dev->of_node;
> +	struct device *dev = ringacc->dev;
> +	struct platform_device *pdev = to_platform_device(dev);
> +	int ret;
> +
> +	if (!node) {
> +		dev_err(dev, "device tree info unavailable\n");
> +		return -ENODEV;
> +	}
> +
> +	ret = of_property_read_u32(node, "ti,num-rings", &ringacc->num_rings);
> +	if (ret) {
> +		dev_err(dev, "ti,num-rings read failure %d\n", ret);
> +		return ret;
> +	}
> +
> +	ringacc->dma_ring_reset_quirk =
> +			of_property_read_bool(node, "ti,dma-ring-reset-quirk");
> +
> +	ringacc->tisci = ti_sci_get_by_phandle(node, "ti,sci");
> +	if (IS_ERR(ringacc->tisci)) {
> +		ret = PTR_ERR(ringacc->tisci);
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "ti,sci read fail %d\n", ret);
> +		ringacc->tisci = NULL;
> +		return ret;
> +	}
> +
> +	ret = of_property_read_u32(node, "ti,sci-dev-id",
> +				   &ringacc->tisci_dev_id);
> +	if (ret) {
> +		dev_err(dev, "ti,sci-dev-id read fail %d\n", ret);
> +		return ret;
> +	}
> +
> +	pdev->id = ringacc->tisci_dev_id;
> +
> +	ringacc->rm_gp_range = devm_ti_sci_get_of_resource(ringacc->tisci, dev,
> +						ringacc->tisci_dev_id,
> +						"ti,sci-rm-range-gp-rings");
> +	if (IS_ERR(ringacc->rm_gp_range)) {
> +		dev_err(dev, "Failed to allocate MSI interrupts\n");
> +		return PTR_ERR(ringacc->rm_gp_range);
> +	}
> +
> +	return ti_sci_inta_msi_domain_alloc_irqs(ringacc->dev,
> +						 ringacc->rm_gp_range);
> +}
> +
> +static int k3_ringacc_probe(struct platform_device *pdev)
> +{
> +	struct k3_ringacc *ringacc;
> +	void __iomem *base_fifo, *base_rt;
> +	struct device *dev = &pdev->dev;
> +	struct resource *res;
> +	int ret, i;
> +
> +	ringacc = devm_kzalloc(dev, sizeof(*ringacc), GFP_KERNEL);
> +	if (!ringacc)
> +		return -ENOMEM;
> +
> +	ringacc->dev = dev;
> +	mutex_init(&ringacc->req_lock);
> +
> +	dev->msi_domain = of_msi_get_domain(dev, dev->of_node,
> +					    DOMAIN_BUS_TI_SCI_INTA_MSI);
> +	if (!dev->msi_domain) {
> +		dev_err(dev, "Failed to get MSI domain\n");
> +		return -EPROBE_DEFER;
> +	}
> +
> +	ret = k3_ringacc_probe_dt(ringacc);
> +	if (ret)
> +		return ret;
> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rt");
> +	base_rt = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(base_rt))
> +		return PTR_ERR(base_rt);
> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fifos");
> +	base_fifo = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(base_fifo))
> +		return PTR_ERR(base_fifo);
> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "proxy_gcfg");
> +	ringacc->proxy_gcfg = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(ringacc->proxy_gcfg))
> +		return PTR_ERR(ringacc->proxy_gcfg);
> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> +					   "proxy_target");
> +	ringacc->proxy_target_base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(ringacc->proxy_target_base))
> +		return PTR_ERR(ringacc->proxy_target_base);
> +
> +	ringacc->num_proxies = dbg_readl(&ringacc->proxy_gcfg->config) &
> +					 K3_RINGACC_PROXY_CFG_THREADS_MASK;
> +
> +	ringacc->rings = devm_kzalloc(dev,
> +				      sizeof(*ringacc->rings) *
> +				      ringacc->num_rings,
> +				      GFP_KERNEL);
> +	ringacc->rings_inuse = devm_kcalloc(dev,
> +					    BITS_TO_LONGS(ringacc->num_rings),
> +					    sizeof(unsigned long), GFP_KERNEL);
> +	ringacc->proxy_inuse = devm_kcalloc(dev,
> +					    BITS_TO_LONGS(ringacc->num_proxies),
> +					    sizeof(unsigned long), GFP_KERNEL);
> +
> +	if (!ringacc->rings || !ringacc->rings_inuse || !ringacc->proxy_inuse)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < ringacc->num_rings; i++) {
> +		ringacc->rings[i].rt = base_rt +
> +				       K3_RINGACC_RT_REGS_STEP * i;
> +		ringacc->rings[i].fifos = base_fifo +
> +					  K3_RINGACC_FIFO_REGS_STEP * i;
> +		ringacc->rings[i].parent = ringacc;
> +		ringacc->rings[i].ring_id = i;
> +		ringacc->rings[i].proxy_id = K3_RINGACC_PROXY_NOT_USED;
> +	}
> +	dev_set_drvdata(dev, ringacc);
> +
> +	ringacc->tisci_ring_ops = &ringacc->tisci->ops.rm_ring_ops;
> +
> +	pm_runtime_enable(dev);
> +	ret = pm_runtime_get_sync(dev);
> +	if (ret < 0) {
> +		pm_runtime_put_noidle(dev);
> +		dev_err(dev, "Failed to enable pm %d\n", ret);
> +		goto err;
> +	}
> +
> +	mutex_lock(&k3_ringacc_list_lock);
> +	list_add_tail(&ringacc->list, &k3_ringacc_list);
> +	mutex_unlock(&k3_ringacc_list_lock);
> +
> +	dev_info(dev, "Ring Accelerator probed rings:%u, gp-rings[%u,%u] sci-dev-id:%u\n",
> +		 ringacc->num_rings,
> +		 ringacc->rm_gp_range->desc[0].start,
> +		 ringacc->rm_gp_range->desc[0].num,
> +		 ringacc->tisci_dev_id);
> +	dev_info(dev, "dma-ring-reset-quirk: %s\n",
> +		 ringacc->dma_ring_reset_quirk ? "enabled" : "disabled");
> +	dev_info(dev, "RA Proxy rev. %08x, num_proxies:%u\n",
> +		 dbg_readl(&ringacc->proxy_gcfg->revision),
> +		 ringacc->num_proxies);
> +	return 0;
> +
> +err:
> +	pm_runtime_disable(dev);
> +	return ret;
> +}
> +
> +static int k3_ringacc_remove(struct platform_device *pdev)
> +{
> +	struct k3_ringacc *ringacc = dev_get_drvdata(&pdev->dev);
> +
> +	pm_runtime_put_sync(&pdev->dev);
> +	pm_runtime_disable(&pdev->dev);
> +
> +	mutex_lock(&k3_ringacc_list_lock);
> +	list_del(&ringacc->list);
> +	mutex_unlock(&k3_ringacc_list_lock);
> +	return 0;
> +}
> +
> +/* Match table for of_platform binding */
> +static const struct of_device_id k3_ringacc_of_match[] = {
> +	{ .compatible = "ti,am654-navss-ringacc", },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, k3_ringacc_of_match);
> +
> +static struct platform_driver k3_ringacc_driver = {
> +	.probe		= k3_ringacc_probe,
> +	.remove		= k3_ringacc_remove,
> +	.driver		= {
> +		.name	= "k3-ringacc",
> +		.of_match_table = k3_ringacc_of_match,
> +	},
> +};
> +module_platform_driver(k3_ringacc_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("TI Ringacc driver for K3 SOCs");
> +MODULE_AUTHOR("Grygorii Strashko <grygorii.strashko@ti.com>");
> diff --git a/include/linux/soc/ti/k3-ringacc.h b/include/linux/soc/ti/k3-ringacc.h
> new file mode 100644
> index 000000000000..debffba48ac9
> --- /dev/null
> +++ b/include/linux/soc/ti/k3-ringacc.h
> @@ -0,0 +1,262 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * K3 Ring Accelerator (RA) subsystem interface
> + *
> + * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
> + */
> +
> +#ifndef __SOC_TI_K3_RINGACC_API_H_
> +#define __SOC_TI_K3_RINGACC_API_H_
> +
> +#include <linux/types.h>
> +
> +struct device_node;
> +
> +/**
> + * enum k3_ring_mode - &struct k3_ring_cfg mode
> + *
> + * RA ring operational modes
> + *
> + * @K3_RINGACC_RING_MODE_RING: Exposed Ring mode for SW direct access
> + * @K3_RINGACC_RING_MODE_MESSAGE: Messaging mode. Messaging mode requires
> + *	that all accesses to the queue must go through this IP so that all
> + *	accesses to the memory are controlled and ordered. This IP then
> + *	controls the entire state of the queue, and SW has no directly control,
> + *	such as through doorbells and cannot access the storage memory directly.
> + *	This is particularly useful when more than one SW or HW entity can be
> + *	the producer and/or consumer at the same time
> + * @K3_RINGACC_RING_MODE_CREDENTIALS: Credentials mode is message mode plus
> + *	stores credentials with each message, requiring the element size to be
> + *	doubled to fit the credentials. Any exposed memory should be protected
> + *	by a firewall from unwanted access
> + * @K3_RINGACC_RING_MODE_QM:  Queue manager mode. This takes the credentials
> + *	mode and adds packet length per element, along with additional read only
> + *	fields for element count and accumulated queue length. The QM mode only
> + *	operates with an 8 byte element size (any other element size is
> + *	illegal), and like in credentials mode each operation uses 2 element
> + *	slots to store the credentials and length fields
> + */
> +enum k3_ring_mode {
> +	K3_RINGACC_RING_MODE_RING = 0,
> +	K3_RINGACC_RING_MODE_MESSAGE,
> +	K3_RINGACC_RING_MODE_CREDENTIALS,
> +	K3_RINGACC_RING_MODE_QM,
> +	K3_RINGACC_RING_MODE_INVALID
> +};
> +
> +/**
> + * enum k3_ring_size - &struct k3_ring_cfg elm_size
> + *
> + * RA ring element's sizes in bytes.
> + */
> +enum k3_ring_size {
> +	K3_RINGACC_RING_ELSIZE_4 = 0,
> +	K3_RINGACC_RING_ELSIZE_8,
> +	K3_RINGACC_RING_ELSIZE_16,
> +	K3_RINGACC_RING_ELSIZE_32,
> +	K3_RINGACC_RING_ELSIZE_64,
> +	K3_RINGACC_RING_ELSIZE_128,
> +	K3_RINGACC_RING_ELSIZE_256,
> +	K3_RINGACC_RING_ELSIZE_INVALID
> +};
> +
> +struct k3_ringacc;
> +struct k3_ring;
> +
> +/**
> + * enum k3_ring_cfg - RA ring configuration structure
> + *
> + * @size: Ring size, number of elements
> + * @elm_size: Ring element size
> + * @mode: Ring operational mode
> + * @flags: Ring configuration flags. Possible values:
> + *	 @K3_RINGACC_RING_SHARED: when set allows to request the same ring
> + *	 few times. It's usable when the same ring is used as Free Host PD ring
> + *	 for different flows, for example.
> + *	 Note: Locking should be done by consumer if required
> + */
> +struct k3_ring_cfg {
> +	u32 size;
> +	enum k3_ring_size elm_size;
> +	enum k3_ring_mode mode;
> +#define K3_RINGACC_RING_SHARED BIT(1)
> +	u32 flags;
> +};
> +
> +#define K3_RINGACC_RING_ID_ANY (-1)
> +
> +/**
> + * of_k3_ringacc_get_by_phandle - find a RA by phandle property
> + * @np: device node
> + * @propname: property name containing phandle on RA node
> + *
> + * Returns pointer on the RA - struct k3_ringacc
> + * or -ENODEV if not found,
> + * or -EPROBE_DEFER if not yet registered
> + */
> +struct k3_ringacc *of_k3_ringacc_get_by_phandle(struct device_node *np,
> +						const char *property);
> +
> +#define K3_RINGACC_RING_USE_PROXY BIT(1)
> +
> +/**
> + * k3_ringacc_request_ring - request ring from ringacc
> + * @ringacc: pointer on ringacc
> + * @id: ring id or K3_RINGACC_RING_ID_ANY for any general purpose ring
> + * @flags:
> + *	@K3_RINGACC_RING_USE_PROXY: if set - proxy will be allocated and
> + *		used to access ring memory. Sopported only for rings in
> + *		Message/Credentials/Queue mode.
> + *
> + * Returns pointer on the Ring - struct k3_ring
> + * or NULL in case of failure.
> + */
> +struct k3_ring *k3_ringacc_request_ring(struct k3_ringacc *ringacc,
> +					int id, u32 flags);
> +
> +/**
> + * k3_ringacc_ring_reset - ring reset
> + * @ring: pointer on Ring
> + *
> + * Resets ring internal state ((hw)occ, (hw)idx).
> + * TODO_GS: ? Ring can be reused without reconfiguration
> + */
> +void k3_ringacc_ring_reset(struct k3_ring *ring);
> +/**
> + * k3_ringacc_ring_reset - ring reset for DMA rings
> + * @ring: pointer on Ring
> + *
> + * Resets ring internal state ((hw)occ, (hw)idx). Should be used for rings
> + * which are read by K3 UDMA, like TX or Free Host PD rings.
> + */
> +void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ);
> +
> +/**
> + * k3_ringacc_ring_free - ring free
> + * @ring: pointer on Ring
> + *
> + * Resets ring and free all alocated resources.
> + */
> +int k3_ringacc_ring_free(struct k3_ring *ring);
> +
> +/**
> + * k3_ringacc_get_ring_id - Get the Ring ID
> + * @ring: pointer on ring
> + *
> + * Returns the Ring ID
> + */
> +u32 k3_ringacc_get_ring_id(struct k3_ring *ring);
> +
> +/**
> + * k3_ringacc_get_ring_irq_num - Get the irq number for the ring
> + * @ring: pointer on ring
> + *
> + * Returns the interrupt number which can be used to request the interrupt
> + */
> +int k3_ringacc_get_ring_irq_num(struct k3_ring *ring);
> +
> +/**
> + * k3_ringacc_ring_cfg - ring configure
> + * @ring: pointer on ring
> + * @cfg: Ring configuration parameters (see &struct k3_ring_cfg)
> + *
> + * Configures ring, including ring memory allocation.
> + * Returns 0 on success, errno otherwise.
> + */
> +int k3_ringacc_ring_cfg(struct k3_ring *ring, struct k3_ring_cfg *cfg);
> +
> +/**
> + * k3_ringacc_ring_get_size - get ring size
> + * @ring: pointer on ring
> + *
> + * Returns ring size in number of elements.
> + */
> +u32 k3_ringacc_ring_get_size(struct k3_ring *ring);
> +
> +/**
> + * k3_ringacc_ring_get_free - get free elements
> + * @ring: pointer on ring
> + *
> + * Returns number of free elements in the ring.
> + */
> +u32 k3_ringacc_ring_get_free(struct k3_ring *ring);
> +
> +/**
> + * k3_ringacc_ring_get_occ - get ring occupancy
> + * @ring: pointer on ring
> + *
> + * Returns total number of valid entries on the ring
> + */
> +u32 k3_ringacc_ring_get_occ(struct k3_ring *ring);
> +
> +/**
> + * k3_ringacc_ring_is_full - checks if ring is full
> + * @ring: pointer on ring
> + *
> + * Returns true if the ring is full
> + */
> +u32 k3_ringacc_ring_is_full(struct k3_ring *ring);
> +
> +/**
> + * k3_ringacc_ring_push - push element to the ring tail
> + * @ring: pointer on ring
> + * @elem: pointer on ring element buffer
> + *
> + * Push one ring element to the ring tail. Size of the ring element is
> + * determined by ring configuration &struct k3_ring_cfg elm_size.
> + *
> + * Returns 0 on success, errno otherwise.
> + */
> +int k3_ringacc_ring_push(struct k3_ring *ring, void *elem);
> +
> +/**
> + * k3_ringacc_ring_pop - pop element from the ring head
> + * @ring: pointer on ring
> + * @elem: pointer on ring element buffer
> + *
> + * Push one ring element from the ring head. Size of the ring element is
> + * determined by ring configuration &struct k3_ring_cfg elm_size..
> + *
> + * Returns 0 on success, errno otherwise.
> + */
> +int k3_ringacc_ring_pop(struct k3_ring *ring, void *elem);
> +
> +/**
> + * k3_ringacc_ring_push_head - push element to the ring head
> + * @ring: pointer on ring
> + * @elem: pointer on ring element buffer
> + *
> + * Push one ring element to the ring head. Size of the ring element is
> + * determined by ring configuration &struct k3_ring_cfg elm_size.
> + *
> + * Returns 0 on success, errno otherwise.
> + * Not Supported by ring modes: K3_RINGACC_RING_MODE_RING
> + */
> +int k3_ringacc_ring_push_head(struct k3_ring *ring, void *elem);
> +
> +/**
> + * k3_ringacc_ring_pop_tail - pop element from the ring tail
> + * @ring: pointer on ring
> + * @elem: pointer on ring element buffer
> + *
> + * Push one ring element from the ring tail. Size of the ring element is
> + * determined by ring configuration &struct k3_ring_cfg elm_size.
> + *
> + * Returns 0 on success, errno otherwise.
> + * Not Supported by ring modes: K3_RINGACC_RING_MODE_RING
> + */
> +int k3_ringacc_ring_pop_tail(struct k3_ring *ring, void *elem);
> +
> +u32 k3_ringacc_get_tisci_dev_id(struct k3_ring *ring);
> +
> +/**
> + * Debugging definitions
> + * TODO: might be removed
> + */
> +#ifdef CONFIG_TI_K3_RINGACC_DEBUG
> +void k3_ringacc_ring_dump(struct k3_ring *ring);
> +#else
> +static inline void k3_ringacc_ring_dump(struct k3_ring *ring) {};
> +#endif
> +
> +#endif /* __SOC_TI_K3_RINGACC_API_H_ */
> 

--
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Vignesh Raghavendra Sept. 9, 2019, 7:25 a.m. UTC | #3
Hi,

On 09/09/19 11:39 AM, Tero Kristo wrote:
[...]
>> diff --git a/drivers/soc/ti/k3-ringacc.c b/drivers/soc/ti/k3-ringacc.c
>> new file mode 100644
>> index 000000000000..401dfc963319
>> --- /dev/null
>> +++ b/drivers/soc/ti/k3-ringacc.c
>> @@ -0,0 +1,1191 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * TI K3 NAVSS Ring Accelerator subsystem driver
>> + *
>> + * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
>> + */
>> +
>> +#include <linux/dma-mapping.h>
>> +#include <linux/io.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/pm_runtime.h>
>> +#include <linux/soc/ti/k3-ringacc.h>
>> +#include <linux/soc/ti/ti_sci_protocol.h>
>> +#include <linux/soc/ti/ti_sci_inta_msi.h>
>> +#include <linux/of_irq.h>
>> +#include <linux/irqdomain.h>
>> +
>> +static LIST_HEAD(k3_ringacc_list);
>> +static DEFINE_MUTEX(k3_ringacc_list_lock);
>> +
>> +#ifdef CONFIG_TI_K3_RINGACC_DEBUG
>> +#define    k3_nav_dbg(dev, arg...) dev_err(dev, arg)
> 
> dev_err seems exaggeration for debug purposes, maybe just dev_info.

If you make this dev_dbg(), it should be possible to just enable
CONFIG_DYNAMIC_DEBUG[1] and control whether or not debug prints are
enabled for this module. Have you explored that option? If that works we
may not need CONFIG_TI_K3_RINGACC_DEBUG at all.

[1] Documentation/admin-guide/dynamic-debug-howto.rst

Regards
Vignesh

> 
>> +static    void dbg_writel(u32 v, void __iomem *reg)
>> +{
>> +    pr_err("WRITEL(32): v(%08X)-->reg(%p)\n", v, reg);
> 
> Again, maybe just pr_info.
> 
>> +    writel(v, reg);
>> +}
>> +
>> +static    u32 dbg_readl(void __iomem *reg)
>> +{
>> +    u32 v;
>> +
>> +    v = readl(reg);
>> +    pr_err("READL(32): v(%08X)<--reg(%p)\n", v, reg);
>> +    return v;
>> +}
>> +#else
>> +#define    k3_nav_dbg(dev, arg...) dev_dbg(dev, arg)
>> +#define dbg_writel(v, reg) writel(v, reg)
> 
> Do you need to use hard writel, writel_relaxed is not enough?
> 
>> +
>> +#define dbg_readl(reg) readl(reg)
> 
> Same as above but for read?
> 
>> +#endif
>> +
>> +#define K3_RINGACC_CFG_RING_SIZE_ELCNT_MASK        GENMASK(19, 0)
>> +
>> +/**
>> + * struct k3_ring_rt_regs -  The RA Control/Status Registers region
>> + */
>> +struct k3_ring_rt_regs {
>> +    u32    resv_16[4];
>> +    u32    db;        /* RT Ring N Doorbell Register */
>> +    u32    resv_4[1];
>> +    u32    occ;        /* RT Ring N Occupancy Register */
>> +    u32    indx;        /* RT Ring N Current Index Register */
>> +    u32    hwocc;        /* RT Ring N Hardware Occupancy Register */
>> +    u32    hwindx;        /* RT Ring N Current Index Register */
>> +};
>> +
>> +#define K3_RINGACC_RT_REGS_STEP    0x1000
>> +
>> +/**
>> + * struct k3_ring_fifo_regs -  The Ring Accelerator Queues Registers
>> region
>> + */
>> +struct k3_ring_fifo_regs {
>> +    u32    head_data[128];        /* Ring Head Entry Data Registers */
>> +    u32    tail_data[128];        /* Ring Tail Entry Data Registers */
>> +    u32    peek_head_data[128];    /* Ring Peek Head Entry Data Regs */
>> +    u32    peek_tail_data[128];    /* Ring Peek Tail Entry Data Regs */
>> +};
>> +
>> +/**
>> + * struct k3_ringacc_proxy_gcfg_regs - RA Proxy Global Config MMIO
>> Region
>> + */
>> +struct k3_ringacc_proxy_gcfg_regs {
>> +    u32    revision;    /* Revision Register */
>> +    u32    config;        /* Config Register */
>> +};
>> +
>> +#define K3_RINGACC_PROXY_CFG_THREADS_MASK        GENMASK(15, 0)
>> +
>> +/**
>> + * struct k3_ringacc_proxy_target_regs -  Proxy Datapath MMIO Region
>> + */
>> +struct k3_ringacc_proxy_target_regs {
>> +    u32    control;    /* Proxy Control Register */
>> +    u32    status;        /* Proxy Status Register */
>> +    u8    resv_512[504];
>> +    u32    data[128];    /* Proxy Data Register */
>> +};
>> +
>> +#define K3_RINGACC_PROXY_TARGET_STEP    0x1000
>> +#define K3_RINGACC_PROXY_NOT_USED    (-1)
>> +
>> +enum k3_ringacc_proxy_access_mode {
>> +    PROXY_ACCESS_MODE_HEAD = 0,
>> +    PROXY_ACCESS_MODE_TAIL = 1,
>> +    PROXY_ACCESS_MODE_PEEK_HEAD = 2,
>> +    PROXY_ACCESS_MODE_PEEK_TAIL = 3,
>> +};
>> +
>> +#define K3_RINGACC_FIFO_WINDOW_SIZE_BYTES  (512U)
>> +#define K3_RINGACC_FIFO_REGS_STEP    0x1000
>> +#define K3_RINGACC_MAX_DB_RING_CNT    (127U)
>> +
>> +/**
>> + * struct k3_ring_ops -  Ring operations
>> + */
>> +struct k3_ring_ops {
>> +    int (*push_tail)(struct k3_ring *ring, void *elm);
>> +    int (*push_head)(struct k3_ring *ring, void *elm);
>> +    int (*pop_tail)(struct k3_ring *ring, void *elm);
>> +    int (*pop_head)(struct k3_ring *ring, void *elm);
>> +};
>> +
>> +/**
>> + * struct k3_ring - RA Ring descriptor
>> + *
>> + * @rt - Ring control/status registers
>> + * @fifos - Ring queues registers
>> + * @proxy - Ring Proxy Datapath registers
>> + * @ring_mem_dma - Ring buffer dma address
>> + * @ring_mem_virt - Ring buffer virt address
>> + * @ops - Ring operations
>> + * @size - Ring size in elements
>> + * @elm_size - Size of the ring element
>> + * @mode - Ring mode
>> + * @flags - flags
>> + * @free - Number of free elements
>> + * @occ - Ring occupancy
>> + * @windex - Write index (only for @K3_RINGACC_RING_MODE_RING)
>> + * @rindex - Read index (only for @K3_RINGACC_RING_MODE_RING)
>> + * @ring_id - Ring Id
>> + * @parent - Pointer on struct @k3_ringacc
>> + * @use_count - Use count for shared rings
>> + * @proxy_id - RA Ring Proxy Id (only if @K3_RINGACC_RING_USE_PROXY)
>> + */
>> +struct k3_ring {
>> +    struct k3_ring_rt_regs __iomem *rt;
>> +    struct k3_ring_fifo_regs __iomem *fifos;
>> +    struct k3_ringacc_proxy_target_regs  __iomem *proxy;
>> +    dma_addr_t    ring_mem_dma;
>> +    void        *ring_mem_virt;
>> +    struct k3_ring_ops *ops;
>> +    u32        size;
>> +    enum k3_ring_size elm_size;
>> +    enum k3_ring_mode mode;
>> +    u32        flags;
>> +#define K3_RING_FLAG_BUSY    BIT(1)
>> +#define K3_RING_FLAG_SHARED    BIT(2)
>> +    u32        free;
>> +    u32        occ;
>> +    u32        windex;
>> +    u32        rindex;
>> +    u32        ring_id;
>> +    struct k3_ringacc    *parent;
>> +    u32        use_count;
>> +    int        proxy_id;
>> +};
>> +
>> +/**
>> + * struct k3_ringacc - Rings accelerator descriptor
>> + *
>> + * @dev - pointer on RA device
>> + * @proxy_gcfg - RA proxy global config registers
>> + * @proxy_target_base - RA proxy datapath region
>> + * @num_rings - number of ring in RA
>> + * @rm_gp_range - general purpose rings range from tisci
>> + * @dma_ring_reset_quirk - DMA reset w/a enable
>> + * @num_proxies - number of RA proxies
>> + * @rings - array of rings descriptors (struct @k3_ring)
>> + * @list - list of RAs in the system
>> + * @tisci - pointer ti-sci handle
>> + * @tisci_ring_ops - ti-sci rings ops
>> + * @tisci_dev_id - ti-sci device id
>> + */
>> +struct k3_ringacc {
>> +    struct device *dev;
>> +    struct k3_ringacc_proxy_gcfg_regs __iomem *proxy_gcfg;
>> +    void __iomem *proxy_target_base;
>> +    u32 num_rings; /* number of rings in Ringacc module */
>> +    unsigned long *rings_inuse;
>> +    struct ti_sci_resource *rm_gp_range;
>> +
>> +    bool dma_ring_reset_quirk;
>> +    u32 num_proxies;
>> +    unsigned long *proxy_inuse;
> 
> proxy_inuse is not documented above.
> 
>> +
>> +    struct k3_ring *rings;
>> +    struct list_head list;
>> +    struct mutex req_lock; /* protect rings allocation */
>> +
>> +    const struct ti_sci_handle *tisci;
>> +    const struct ti_sci_rm_ringacc_ops *tisci_ring_ops;
>> +    u32  tisci_dev_id;
>> +};
>> +
>> +static long k3_ringacc_ring_get_fifo_pos(struct k3_ring *ring)
>> +{
>> +    return K3_RINGACC_FIFO_WINDOW_SIZE_BYTES -
>> +           (4 << ring->elm_size);
>> +}
>> +
>> +static void *k3_ringacc_get_elm_addr(struct k3_ring *ring, u32 idx)
>> +{
>> +    return (idx * (4 << ring->elm_size) + ring->ring_mem_virt);
> 
> The arithmetic here seems backwards compared to most other code I've
> seen. It would be more readable if you have it like:
> 
> ring->ring_mem_virt + idx * (4 << ring->elm_size);
> 
>> +}
>> +
>> +static int k3_ringacc_ring_push_mem(struct k3_ring *ring, void *elem);
>> +static int k3_ringacc_ring_pop_mem(struct k3_ring *ring, void *elem);
>> +
>> +static struct k3_ring_ops k3_ring_mode_ring_ops = {
>> +        .push_tail = k3_ringacc_ring_push_mem,
>> +        .pop_head = k3_ringacc_ring_pop_mem,
>> +};
>> +
>> +static int k3_ringacc_ring_push_io(struct k3_ring *ring, void *elem);
>> +static int k3_ringacc_ring_pop_io(struct k3_ring *ring, void *elem);
>> +static int k3_ringacc_ring_push_head_io(struct k3_ring *ring, void
>> *elem);
>> +static int k3_ringacc_ring_pop_tail_io(struct k3_ring *ring, void
>> *elem);
>> +
>> +static struct k3_ring_ops k3_ring_mode_msg_ops = {
>> +        .push_tail = k3_ringacc_ring_push_io,
>> +        .push_head = k3_ringacc_ring_push_head_io,
>> +        .pop_tail = k3_ringacc_ring_pop_tail_io,
>> +        .pop_head = k3_ringacc_ring_pop_io,
>> +};
>> +
>> +static int k3_ringacc_ring_push_head_proxy(struct k3_ring *ring, void
>> *elem);
>> +static int k3_ringacc_ring_push_tail_proxy(struct k3_ring *ring, void
>> *elem);
>> +static int k3_ringacc_ring_pop_head_proxy(struct k3_ring *ring, void
>> *elem);
>> +static int k3_ringacc_ring_pop_tail_proxy(struct k3_ring *ring, void
>> *elem);
>> +
>> +static struct k3_ring_ops k3_ring_mode_proxy_ops = {
>> +        .push_tail = k3_ringacc_ring_push_tail_proxy,
>> +        .push_head = k3_ringacc_ring_push_head_proxy,
>> +        .pop_tail = k3_ringacc_ring_pop_tail_proxy,
>> +        .pop_head = k3_ringacc_ring_pop_head_proxy,
>> +};
>> +
>> +#ifdef CONFIG_TI_K3_RINGACC_DEBUG
>> +void k3_ringacc_ring_dump(struct k3_ring *ring)
>> +{
>> +    struct device *dev = ring->parent->dev;
>> +
>> +    k3_nav_dbg(dev, "dump ring: %d\n", ring->ring_id);
>> +    k3_nav_dbg(dev, "dump mem virt %p, dma %pad\n",
>> +           ring->ring_mem_virt, &ring->ring_mem_dma);
>> +    k3_nav_dbg(dev, "dump elmsize %d, size %d, mode %d, proxy_id %d\n",
>> +           ring->elm_size, ring->size, ring->mode, ring->proxy_id);
>> +
>> +    k3_nav_dbg(dev, "dump ring_rt_regs: db%08x\n",
>> +           readl(&ring->rt->db));
> 
> Why not use readl_relaxed in this func?
> 
>> +    k3_nav_dbg(dev, "dump occ%08x\n",
>> +           readl(&ring->rt->occ));
>> +    k3_nav_dbg(dev, "dump indx%08x\n",
>> +           readl(&ring->rt->indx));
>> +    k3_nav_dbg(dev, "dump hwocc%08x\n",
>> +           readl(&ring->rt->hwocc));
>> +    k3_nav_dbg(dev, "dump hwindx%08x\n",
>> +           readl(&ring->rt->hwindx));
>> +
>> +    if (ring->ring_mem_virt)
>> +        print_hex_dump(KERN_ERR, "dump ring_mem_virt ",
>> +                   DUMP_PREFIX_NONE, 16, 1,
>> +                   ring->ring_mem_virt, 16 * 8, false);
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_dump);
> 
> Do you really need to export a debug function?
> 
>> +#endif
>> +
>> +struct k3_ring *k3_ringacc_request_ring(struct k3_ringacc *ringacc,
>> +                    int id, u32 flags)
>> +{
>> +    int proxy_id = K3_RINGACC_PROXY_NOT_USED;
>> +
>> +    mutex_lock(&ringacc->req_lock);
>> +
>> +    if (id == K3_RINGACC_RING_ID_ANY) {
>> +        /* Request for any general purpose ring */
>> +        struct ti_sci_resource_desc *gp_rings =
>> +                        &ringacc->rm_gp_range->desc[0];
>> +        unsigned long size;
>> +
>> +        size = gp_rings->start + gp_rings->num;
>> +        id = find_next_zero_bit(ringacc->rings_inuse, size,
>> +                    gp_rings->start);
>> +        if (id == size)
>> +            goto error;
>> +    } else if (id < 0) {
>> +        goto error;
>> +    }
>> +
>> +    if (test_bit(id, ringacc->rings_inuse) &&
>> +        !(ringacc->rings[id].flags & K3_RING_FLAG_SHARED))
>> +        goto error;
>> +    else if (ringacc->rings[id].flags & K3_RING_FLAG_SHARED)
>> +        goto out;
>> +
>> +    if (flags & K3_RINGACC_RING_USE_PROXY) {
>> +        proxy_id = find_next_zero_bit(ringacc->proxy_inuse,
>> +                          ringacc->num_proxies, 0);
>> +        if (proxy_id == ringacc->num_proxies)
>> +            goto error;
>> +    }
>> +
>> +    if (!try_module_get(ringacc->dev->driver->owner))
>> +        goto error;
>> +
>> +    if (proxy_id != K3_RINGACC_PROXY_NOT_USED) {
>> +        set_bit(proxy_id, ringacc->proxy_inuse);
>> +        ringacc->rings[id].proxy_id = proxy_id;
>> +        k3_nav_dbg(ringacc->dev, "Giving ring#%d proxy#%d\n",
>> +               id, proxy_id);
>> +    } else {
>> +        k3_nav_dbg(ringacc->dev, "Giving ring#%d\n", id);
>> +    }
>> +
>> +    set_bit(id, ringacc->rings_inuse);
>> +out:
>> +    ringacc->rings[id].use_count++;
>> +    mutex_unlock(&ringacc->req_lock);
>> +    return &ringacc->rings[id];
>> +
>> +error:
>> +    mutex_unlock(&ringacc->req_lock);
>> +    return NULL;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_request_ring);
>> +
>> +static void k3_ringacc_ring_reset_sci(struct k3_ring *ring)
>> +{
>> +    struct k3_ringacc *ringacc = ring->parent;
>> +    int ret;
>> +
>> +    ret = ringacc->tisci_ring_ops->config(
>> +            ringacc->tisci,
>> +            TI_SCI_MSG_VALUE_RM_RING_COUNT_VALID,
>> +            ringacc->tisci_dev_id,
>> +            ring->ring_id,
>> +            0,
>> +            0,
>> +            ring->size,
>> +            0,
>> +            0,
>> +            0);
>> +    if (ret)
>> +        dev_err(ringacc->dev, "TISCI reset ring fail (%d) ring_idx
>> %d\n",
>> +            ret, ring->ring_id);
> 
> Return value of sci ops is masked, why not return it and let the caller
> handle it properly?
> 
> Same comment for anything similar that follows.
> 
>> +}
>> +
>> +void k3_ringacc_ring_reset(struct k3_ring *ring)
>> +{
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return;
>> +
>> +    ring->occ = 0;
>> +    ring->free = 0;
>> +    ring->rindex = 0;
>> +    ring->windex = 0;
>> +
>> +    k3_ringacc_ring_reset_sci(ring);
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset);
>> +
>> +static void k3_ringacc_ring_reconfig_qmode_sci(struct k3_ring *ring,
>> +                           enum k3_ring_mode mode)
>> +{
>> +    struct k3_ringacc *ringacc = ring->parent;
>> +    int ret;
>> +
>> +    ret = ringacc->tisci_ring_ops->config(
>> +            ringacc->tisci,
>> +            TI_SCI_MSG_VALUE_RM_RING_MODE_VALID,
>> +            ringacc->tisci_dev_id,
>> +            ring->ring_id,
>> +            0,
>> +            0,
>> +            0,
>> +            mode,
>> +            0,
>> +            0);
>> +    if (ret)
>> +        dev_err(ringacc->dev, "TISCI reconf qmode fail (%d) ring_idx
>> %d\n",
>> +            ret, ring->ring_id);
>> +}
>> +
>> +void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ)
>> +{
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return;
>> +
>> +    if (!ring->parent->dma_ring_reset_quirk)
>> +        return;
>> +
>> +    if (!occ)
>> +        occ = dbg_readl(&ring->rt->occ);
>> +
>> +    if (occ) {
>> +        u32 db_ring_cnt, db_ring_cnt_cur;
>> +
>> +        k3_nav_dbg(ring->parent->dev, "%s %u occ: %u\n", __func__,
>> +               ring->ring_id, occ);
>> +        /* 2. Reset the ring */
> 
> 2? Where is 1?
> 
>> +        k3_ringacc_ring_reset_sci(ring);
>> +
>> +        /*
>> +         * 3. Setup the ring in ring/doorbell mode
>> +         * (if not already in this mode)
>> +         */
>> +        if (ring->mode != K3_RINGACC_RING_MODE_RING)
>> +            k3_ringacc_ring_reconfig_qmode_sci(
>> +                    ring, K3_RINGACC_RING_MODE_RING);
>> +        /*
>> +         * 4. Ring the doorbell 2**22 – ringOcc times.
>> +         * This will wrap the internal UDMAP ring state occupancy
>> +         * counter (which is 21-bits wide) to 0.
>> +         */
>> +        db_ring_cnt = (1U << 22) - occ;
>> +
>> +        while (db_ring_cnt != 0) {
>> +            /*
>> +             * Ring the doorbell with the maximum count each
>> +             * iteration if possible to minimize the total
>> +             * of writes
>> +             */
>> +            if (db_ring_cnt > K3_RINGACC_MAX_DB_RING_CNT)
>> +                db_ring_cnt_cur = K3_RINGACC_MAX_DB_RING_CNT;
>> +            else
>> +                db_ring_cnt_cur = db_ring_cnt;
>> +
>> +            writel(db_ring_cnt_cur, &ring->rt->db);
>> +            db_ring_cnt -= db_ring_cnt_cur;
>> +        }
>> +
>> +        /* 5. Restore the original ring mode (if not ring mode) */
>> +        if (ring->mode != K3_RINGACC_RING_MODE_RING)
>> +            k3_ringacc_ring_reconfig_qmode_sci(ring, ring->mode);
>> +    }
>> +
>> +    /* 2. Reset the ring */
> 
> Again 2?
> 
>> +    k3_ringacc_ring_reset(ring);
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset_dma);
>> +
>> +static void k3_ringacc_ring_free_sci(struct k3_ring *ring)
>> +{
>> +    struct k3_ringacc *ringacc = ring->parent;
>> +    int ret;
>> +
>> +    ret = ringacc->tisci_ring_ops->config(
>> +            ringacc->tisci,
>> +            TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
>> +            ringacc->tisci_dev_id,
>> +            ring->ring_id,
>> +            0,
>> +            0,
>> +            0,
>> +            0,
>> +            0,
>> +            0);
>> +    if (ret)
>> +        dev_err(ringacc->dev, "TISCI ring free fail (%d) ring_idx %d\n",
>> +            ret, ring->ring_id);
>> +}
>> +
>> +int k3_ringacc_ring_free(struct k3_ring *ring)
>> +{
>> +    struct k3_ringacc *ringacc;
>> +
>> +    if (!ring)
>> +        return -EINVAL;
>> +
>> +    ringacc = ring->parent;
>> +
>> +    k3_nav_dbg(ring->parent->dev, "flags: 0x%08x\n", ring->flags);
>> +
>> +    if (!test_bit(ring->ring_id, ringacc->rings_inuse))
>> +        return -EINVAL;
>> +
>> +    mutex_lock(&ringacc->req_lock);
>> +
>> +    if (--ring->use_count)
>> +        goto out;
>> +
>> +    if (!(ring->flags & K3_RING_FLAG_BUSY))
>> +        goto no_init;
>> +
>> +    k3_ringacc_ring_free_sci(ring);
>> +
>> +    dma_free_coherent(ringacc->dev,
>> +              ring->size * (4 << ring->elm_size),
>> +              ring->ring_mem_virt, ring->ring_mem_dma);
>> +    ring->flags = 0;
>> +    ring->ops = NULL;
>> +    if (ring->proxy_id != K3_RINGACC_PROXY_NOT_USED) {
>> +        clear_bit(ring->proxy_id, ringacc->proxy_inuse);
>> +        ring->proxy = NULL;
>> +        ring->proxy_id = K3_RINGACC_PROXY_NOT_USED;
>> +    }
>> +
>> +no_init:
>> +    clear_bit(ring->ring_id, ringacc->rings_inuse);
>> +
>> +    module_put(ringacc->dev->driver->owner);
>> +
>> +out:
>> +    mutex_unlock(&ringacc->req_lock);
>> +    return 0;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_free);
>> +
>> +u32 k3_ringacc_get_ring_id(struct k3_ring *ring)
>> +{
>> +    if (!ring)
>> +        return -EINVAL;
>> +
>> +    return ring->ring_id;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_id);
>> +
>> +u32 k3_ringacc_get_tisci_dev_id(struct k3_ring *ring)
>> +{
>> +    if (!ring)
>> +        return -EINVAL;
>> +
> 
> What if parent is NULL? Can it ever be here?
> 
>> +    return ring->parent->tisci_dev_id;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_get_tisci_dev_id);
>> +
>> +int k3_ringacc_get_ring_irq_num(struct k3_ring *ring)
>> +{
>> +    int irq_num;
>> +
>> +    if (!ring)
>> +        return -EINVAL;
>> +
>> +    irq_num = ti_sci_inta_msi_get_virq(ring->parent->dev,
>> ring->ring_id);
>> +    if (irq_num <= 0)
>> +        irq_num = -EINVAL;
>> +    return irq_num;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_irq_num);
>> +
>> +static int k3_ringacc_ring_cfg_sci(struct k3_ring *ring)
>> +{
>> +    struct k3_ringacc *ringacc = ring->parent;
>> +    u32 ring_idx;
>> +    int ret;
>> +
>> +    if (!ringacc->tisci)
>> +        return -EINVAL;
>> +
>> +    ring_idx = ring->ring_id;
>> +    ret = ringacc->tisci_ring_ops->config(
>> +            ringacc->tisci,
>> +            TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
>> +            ringacc->tisci_dev_id,
>> +            ring_idx,
>> +            lower_32_bits(ring->ring_mem_dma),
>> +            upper_32_bits(ring->ring_mem_dma),
>> +            ring->size,
>> +            ring->mode,
>> +            ring->elm_size,
>> +            0);
>> +    if (ret)
>> +        dev_err(ringacc->dev, "TISCI config ring fail (%d) ring_idx
>> %d\n",
>> +            ret, ring_idx);
>> +
>> +    return ret;
>> +}
>> +
>> +int k3_ringacc_ring_cfg(struct k3_ring *ring, struct k3_ring_cfg *cfg)
>> +{
>> +    struct k3_ringacc *ringacc = ring->parent;
>> +    int ret = 0;
>> +
>> +    if (!ring || !cfg)
>> +        return -EINVAL;
>> +    if (cfg->elm_size > K3_RINGACC_RING_ELSIZE_256 ||
>> +        cfg->mode > K3_RINGACC_RING_MODE_QM ||
>> +        cfg->size & ~K3_RINGACC_CFG_RING_SIZE_ELCNT_MASK ||
>> +        !test_bit(ring->ring_id, ringacc->rings_inuse))
>> +        return -EINVAL;
>> +
>> +    if (ring->use_count != 1)
> 
> Hmm, isn't this a failure actually?
> 
>> +        return 0;
>> +
>> +    ring->size = cfg->size;
>> +    ring->elm_size = cfg->elm_size;
>> +    ring->mode = cfg->mode;
>> +    ring->occ = 0;
>> +    ring->free = 0;
>> +    ring->rindex = 0;
>> +    ring->windex = 0;
>> +
>> +    if (ring->proxy_id != K3_RINGACC_PROXY_NOT_USED)
>> +        ring->proxy = ringacc->proxy_target_base +
>> +                  ring->proxy_id * K3_RINGACC_PROXY_TARGET_STEP;
>> +
>> +    switch (ring->mode) {
>> +    case K3_RINGACC_RING_MODE_RING:
>> +        ring->ops = &k3_ring_mode_ring_ops;
>> +        break;
>> +    case K3_RINGACC_RING_MODE_QM:
>> +        /*
>> +         * In Queue mode elm_size can be 8 only and each operation
>> +         * uses 2 element slots
>> +         */
>> +        if (cfg->elm_size != K3_RINGACC_RING_ELSIZE_8 ||
>> +            cfg->size % 2)
>> +            goto err_free_proxy;
>> +        /* else, fall through */
>> +    case K3_RINGACC_RING_MODE_MESSAGE:
>> +        if (ring->proxy)
>> +            ring->ops = &k3_ring_mode_proxy_ops;
>> +        else
>> +            ring->ops = &k3_ring_mode_msg_ops;
>> +        break;
>> +    default:
>> +        ring->ops = NULL;
>> +        ret = -EINVAL;
>> +        goto err_free_proxy;
>> +    };
>> +
>> +    ring->ring_mem_virt =
>> +            dma_alloc_coherent(ringacc->dev,
>> +                       ring->size * (4 << ring->elm_size),
>> +                       &ring->ring_mem_dma, GFP_KERNEL);
>> +    if (!ring->ring_mem_virt) {
>> +        dev_err(ringacc->dev, "Failed to alloc ring mem\n");
>> +        ret = -ENOMEM;
>> +        goto err_free_ops;
>> +    }
>> +
>> +    ret = k3_ringacc_ring_cfg_sci(ring);
>> +
>> +    if (ret)
>> +        goto err_free_mem;
>> +
>> +    ring->flags |= K3_RING_FLAG_BUSY;
>> +    ring->flags |= (cfg->flags & K3_RINGACC_RING_SHARED) ?
>> +            K3_RING_FLAG_SHARED : 0;
>> +
>> +    k3_ringacc_ring_dump(ring);
>> +
>> +    return 0;
>> +
>> +err_free_mem:
>> +    dma_free_coherent(ringacc->dev,
>> +              ring->size * (4 << ring->elm_size),
>> +              ring->ring_mem_virt,
>> +              ring->ring_mem_dma);
>> +err_free_ops:
>> +    ring->ops = NULL;
>> +err_free_proxy:
>> +    ring->proxy = NULL;
>> +    return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_cfg);
>> +
>> +u32 k3_ringacc_ring_get_size(struct k3_ring *ring)
>> +{
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return -EINVAL;
>> +
>> +    return ring->size;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_size);
>> +
>> +u32 k3_ringacc_ring_get_free(struct k3_ring *ring)
>> +{
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return -EINVAL;
>> +
>> +    if (!ring->free)
>> +        ring->free = ring->size - dbg_readl(&ring->rt->occ);
>> +
>> +    return ring->free;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_free);
>> +
>> +u32 k3_ringacc_ring_get_occ(struct k3_ring *ring)
>> +{
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return -EINVAL;
>> +
>> +    return dbg_readl(&ring->rt->occ);
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_occ);
>> +
>> +u32 k3_ringacc_ring_is_full(struct k3_ring *ring)
>> +{
>> +    return !k3_ringacc_ring_get_free(ring);
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_is_full);
>> +
>> +enum k3_ringacc_access_mode {
>> +    K3_RINGACC_ACCESS_MODE_PUSH_HEAD,
>> +    K3_RINGACC_ACCESS_MODE_POP_HEAD,
>> +    K3_RINGACC_ACCESS_MODE_PUSH_TAIL,
>> +    K3_RINGACC_ACCESS_MODE_POP_TAIL,
>> +    K3_RINGACC_ACCESS_MODE_PEEK_HEAD,
>> +    K3_RINGACC_ACCESS_MODE_PEEK_TAIL,
>> +};
>> +
>> +static int k3_ringacc_ring_cfg_proxy(struct k3_ring *ring,
>> +                     enum k3_ringacc_proxy_access_mode mode)
>> +{
>> +    u32 val;
>> +
>> +    val = ring->ring_id;
>> +    val |= mode << 16;
>> +    val |= ring->elm_size << 24;
> 
> Would be nice to have these magic shifts as defines.
> 
>> +    dbg_writel(val, &ring->proxy->control);
>> +    return 0;
>> +}
>> +
>> +static int k3_ringacc_ring_access_proxy(struct k3_ring *ring, void
>> *elem,
>> +                    enum k3_ringacc_access_mode access_mode)
>> +{
>> +    void __iomem *ptr;
>> +
>> +    ptr = (void __iomem *)&ring->proxy->data;
>> +
>> +    switch (access_mode) {
>> +    case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
>> +    case K3_RINGACC_ACCESS_MODE_POP_HEAD:
>> +        k3_ringacc_ring_cfg_proxy(ring, PROXY_ACCESS_MODE_HEAD);
>> +        break;
>> +    case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
>> +    case K3_RINGACC_ACCESS_MODE_POP_TAIL:
>> +        k3_ringacc_ring_cfg_proxy(ring, PROXY_ACCESS_MODE_TAIL);
>> +        break;
>> +    default:
>> +        return -EINVAL;
>> +    }
>> +
>> +    ptr += k3_ringacc_ring_get_fifo_pos(ring);
>> +
>> +    switch (access_mode) {
>> +    case K3_RINGACC_ACCESS_MODE_POP_HEAD:
>> +    case K3_RINGACC_ACCESS_MODE_POP_TAIL:
>> +        k3_nav_dbg(ring->parent->dev, "proxy:memcpy_fromio(x): -->
>> ptr(%p), mode:%d\n",
>> +               ptr, access_mode);
>> +        memcpy_fromio(elem, ptr, (4 << ring->elm_size));
>> +        ring->occ--;
>> +        break;
>> +    case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
>> +    case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
>> +        k3_nav_dbg(ring->parent->dev, "proxy:memcpy_toio(x): -->
>> ptr(%p), mode:%d\n",
>> +               ptr, access_mode);
>> +        memcpy_toio(ptr, elem, (4 << ring->elm_size));
>> +        ring->free--;
>> +        break;
>> +    default:
>> +        return -EINVAL;
>> +    }
>> +
>> +    k3_nav_dbg(ring->parent->dev, "proxy: free%d occ%d\n",
>> +           ring->free, ring->occ);
>> +    return 0;
>> +}
>> +
>> +static int k3_ringacc_ring_push_head_proxy(struct k3_ring *ring, void
>> *elem)
>> +{
>> +    return k3_ringacc_ring_access_proxy(ring, elem,
>> +                        K3_RINGACC_ACCESS_MODE_PUSH_HEAD);
>> +}
>> +
>> +static int k3_ringacc_ring_push_tail_proxy(struct k3_ring *ring, void
>> *elem)
>> +{
>> +    return k3_ringacc_ring_access_proxy(ring, elem,
>> +                        K3_RINGACC_ACCESS_MODE_PUSH_TAIL);
>> +}
>> +
>> +static int k3_ringacc_ring_pop_head_proxy(struct k3_ring *ring, void
>> *elem)
>> +{
>> +    return k3_ringacc_ring_access_proxy(ring, elem,
>> +                        K3_RINGACC_ACCESS_MODE_POP_HEAD);
>> +}
>> +
>> +static int k3_ringacc_ring_pop_tail_proxy(struct k3_ring *ring, void
>> *elem)
>> +{
>> +    return k3_ringacc_ring_access_proxy(ring, elem,
>> +                        K3_RINGACC_ACCESS_MODE_POP_HEAD);
>> +}
>> +
>> +static int k3_ringacc_ring_access_io(struct k3_ring *ring, void *elem,
>> +                     enum k3_ringacc_access_mode access_mode)
>> +{
>> +    void __iomem *ptr;
>> +
>> +    switch (access_mode) {
>> +    case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
>> +    case K3_RINGACC_ACCESS_MODE_POP_HEAD:
>> +        ptr = (void __iomem *)&ring->fifos->head_data;
>> +        break;
>> +    case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
>> +    case K3_RINGACC_ACCESS_MODE_POP_TAIL:
>> +        ptr = (void __iomem *)&ring->fifos->tail_data;
>> +        break;
>> +    default:
>> +        return -EINVAL;
>> +    }
>> +
>> +    ptr += k3_ringacc_ring_get_fifo_pos(ring);
>> +
>> +    switch (access_mode) {
>> +    case K3_RINGACC_ACCESS_MODE_POP_HEAD:
>> +    case K3_RINGACC_ACCESS_MODE_POP_TAIL:
>> +        k3_nav_dbg(ring->parent->dev, "memcpy_fromio(x): --> ptr(%p),
>> mode:%d\n",
>> +               ptr, access_mode);
>> +        memcpy_fromio(elem, ptr, (4 << ring->elm_size));
>> +        ring->occ--;
>> +        break;
>> +    case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
>> +    case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
>> +        k3_nav_dbg(ring->parent->dev, "memcpy_toio(x): --> ptr(%p),
>> mode:%d\n",
>> +               ptr, access_mode);
>> +        memcpy_toio(ptr, elem, (4 << ring->elm_size));
>> +        ring->free--;
>> +        break;
>> +    default:
>> +        return -EINVAL;
>> +    }
>> +
>> +    k3_nav_dbg(ring->parent->dev, "free%d index%d occ%d index%d\n",
>> +           ring->free, ring->windex, ring->occ, ring->rindex);
>> +    return 0;
>> +}
>> +
>> +static int k3_ringacc_ring_push_head_io(struct k3_ring *ring, void
>> *elem)
>> +{
>> +    return k3_ringacc_ring_access_io(ring, elem,
>> +                     K3_RINGACC_ACCESS_MODE_PUSH_HEAD);
>> +}
>> +
>> +static int k3_ringacc_ring_push_io(struct k3_ring *ring, void *elem)
>> +{
>> +    return k3_ringacc_ring_access_io(ring, elem,
>> +                     K3_RINGACC_ACCESS_MODE_PUSH_TAIL);
>> +}
>> +
>> +static int k3_ringacc_ring_pop_io(struct k3_ring *ring, void *elem)
>> +{
>> +    return k3_ringacc_ring_access_io(ring, elem,
>> +                     K3_RINGACC_ACCESS_MODE_POP_HEAD);
>> +}
>> +
>> +static int k3_ringacc_ring_pop_tail_io(struct k3_ring *ring, void *elem)
>> +{
>> +    return k3_ringacc_ring_access_io(ring, elem,
>> +                     K3_RINGACC_ACCESS_MODE_POP_HEAD);
>> +}
>> +
>> +static int k3_ringacc_ring_push_mem(struct k3_ring *ring, void *elem)
>> +{
>> +    void *elem_ptr;
>> +
>> +    elem_ptr = k3_ringacc_get_elm_addr(ring, ring->windex);
>> +
>> +    memcpy(elem_ptr, elem, (4 << ring->elm_size));
>> +
>> +    ring->windex = (ring->windex + 1) % ring->size;
>> +    ring->free--;
>> +    dbg_writel(1, &ring->rt->db);
>> +
>> +    k3_nav_dbg(ring->parent->dev, "ring_push_mem: free%d index%d\n",
>> +           ring->free, ring->windex);
>> +
>> +    return 0;
>> +}
>> +
>> +static int k3_ringacc_ring_pop_mem(struct k3_ring *ring, void *elem)
>> +{
>> +    void *elem_ptr;
>> +
>> +    elem_ptr = k3_ringacc_get_elm_addr(ring, ring->rindex);
>> +
>> +    memcpy(elem, elem_ptr, (4 << ring->elm_size));
>> +
>> +    ring->rindex = (ring->rindex + 1) % ring->size;
>> +    ring->occ--;
>> +    dbg_writel(-1, &ring->rt->db);
>> +
>> +    k3_nav_dbg(ring->parent->dev, "ring_pop_mem: occ%d index%d
>> pos_ptr%p\n",
>> +           ring->occ, ring->rindex, elem_ptr);
>> +    return 0;
>> +}
>> +
>> +int k3_ringacc_ring_push(struct k3_ring *ring, void *elem)
>> +{
>> +    int ret = -EOPNOTSUPP;
>> +
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return -EINVAL;
>> +
>> +    k3_nav_dbg(ring->parent->dev, "ring_push: free%d index%d\n",
>> +           ring->free, ring->windex);
>> +
>> +    if (k3_ringacc_ring_is_full(ring))
>> +        return -ENOMEM;
>> +
>> +    if (ring->ops && ring->ops->push_tail)
>> +        ret = ring->ops->push_tail(ring, elem);
>> +
>> +    return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_push);
>> +
>> +int k3_ringacc_ring_push_head(struct k3_ring *ring, void *elem)
>> +{
>> +    int ret = -EOPNOTSUPP;
>> +
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return -EINVAL;
>> +
>> +    k3_nav_dbg(ring->parent->dev, "ring_push_head: free%d index%d\n",
>> +           ring->free, ring->windex);
>> +
>> +    if (k3_ringacc_ring_is_full(ring))
>> +        return -ENOMEM;
>> +
>> +    if (ring->ops && ring->ops->push_head)
>> +        ret = ring->ops->push_head(ring, elem);
>> +
>> +    return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_push_head);
>> +
>> +int k3_ringacc_ring_pop(struct k3_ring *ring, void *elem)
>> +{
>> +    int ret = -EOPNOTSUPP;
>> +
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return -EINVAL;
>> +
>> +    if (!ring->occ)
>> +        ring->occ = k3_ringacc_ring_get_occ(ring);
>> +
>> +    k3_nav_dbg(ring->parent->dev, "ring_pop: occ%d index%d\n",
>> +           ring->occ, ring->rindex);
>> +
>> +    if (!ring->occ)
>> +        return -ENODATA;
>> +
>> +    if (ring->ops && ring->ops->pop_head)
>> +        ret = ring->ops->pop_head(ring, elem);
>> +
>> +    return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_pop);
>> +
>> +int k3_ringacc_ring_pop_tail(struct k3_ring *ring, void *elem)
>> +{
>> +    int ret = -EOPNOTSUPP;
>> +
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return -EINVAL;
>> +
>> +    if (!ring->occ)
>> +        ring->occ = k3_ringacc_ring_get_occ(ring);
>> +
>> +    k3_nav_dbg(ring->parent->dev, "ring_pop_tail: occ%d index%d\n",
>> +           ring->occ, ring->rindex);
>> +
>> +    if (!ring->occ)
>> +        return -ENODATA;
>> +
>> +    if (ring->ops && ring->ops->pop_tail)
>> +        ret = ring->ops->pop_tail(ring, elem);
>> +
>> +    return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_pop_tail);
>> +
>> +struct k3_ringacc *of_k3_ringacc_get_by_phandle(struct device_node *np,
>> +                        const char *property)
>> +{
>> +    struct device_node *ringacc_np;
>> +    struct k3_ringacc *ringacc = ERR_PTR(-EPROBE_DEFER);
>> +    struct k3_ringacc *entry;
>> +
>> +    ringacc_np = of_parse_phandle(np, property, 0);
>> +    if (!ringacc_np)
>> +        return ERR_PTR(-ENODEV);
>> +
>> +    mutex_lock(&k3_ringacc_list_lock);
>> +    list_for_each_entry(entry, &k3_ringacc_list, list)
>> +        if (entry->dev->of_node == ringacc_np) {
>> +            ringacc = entry;
>> +            break;
>> +        }
>> +    mutex_unlock(&k3_ringacc_list_lock);
>> +    of_node_put(ringacc_np);
>> +
>> +    return ringacc;
>> +}
>> +EXPORT_SYMBOL_GPL(of_k3_ringacc_get_by_phandle);
>> +
>> +static int k3_ringacc_probe_dt(struct k3_ringacc *ringacc)
>> +{
>> +    struct device_node *node = ringacc->dev->of_node;
>> +    struct device *dev = ringacc->dev;
>> +    struct platform_device *pdev = to_platform_device(dev);
>> +    int ret;
>> +
>> +    if (!node) {
>> +        dev_err(dev, "device tree info unavailable\n");
>> +        return -ENODEV;
>> +    }
>> +
>> +    ret = of_property_read_u32(node, "ti,num-rings",
>> &ringacc->num_rings);
>> +    if (ret) {
>> +        dev_err(dev, "ti,num-rings read failure %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    ringacc->dma_ring_reset_quirk =
>> +            of_property_read_bool(node, "ti,dma-ring-reset-quirk");
>> +
>> +    ringacc->tisci = ti_sci_get_by_phandle(node, "ti,sci");
>> +    if (IS_ERR(ringacc->tisci)) {
>> +        ret = PTR_ERR(ringacc->tisci);
>> +        if (ret != -EPROBE_DEFER)
>> +            dev_err(dev, "ti,sci read fail %d\n", ret);
>> +        ringacc->tisci = NULL;
>> +        return ret;
>> +    }
>> +
>> +    ret = of_property_read_u32(node, "ti,sci-dev-id",
>> +                   &ringacc->tisci_dev_id);
>> +    if (ret) {
>> +        dev_err(dev, "ti,sci-dev-id read fail %d\n", ret);
>> +        return ret;
>> +    }
>> +
>> +    pdev->id = ringacc->tisci_dev_id;
>> +
>> +    ringacc->rm_gp_range =
>> devm_ti_sci_get_of_resource(ringacc->tisci, dev,
>> +                        ringacc->tisci_dev_id,
>> +                        "ti,sci-rm-range-gp-rings");
>> +    if (IS_ERR(ringacc->rm_gp_range)) {
>> +        dev_err(dev, "Failed to allocate MSI interrupts\n");
>> +        return PTR_ERR(ringacc->rm_gp_range);
>> +    }
>> +
>> +    return ti_sci_inta_msi_domain_alloc_irqs(ringacc->dev,
>> +                         ringacc->rm_gp_range);
>> +}
>> +
>> +static int k3_ringacc_probe(struct platform_device *pdev)
>> +{
>> +    struct k3_ringacc *ringacc;
>> +    void __iomem *base_fifo, *base_rt;
>> +    struct device *dev = &pdev->dev;
>> +    struct resource *res;
>> +    int ret, i;
>> +
>> +    ringacc = devm_kzalloc(dev, sizeof(*ringacc), GFP_KERNEL);
>> +    if (!ringacc)
>> +        return -ENOMEM;
>> +
>> +    ringacc->dev = dev;
>> +    mutex_init(&ringacc->req_lock);
>> +
>> +    dev->msi_domain = of_msi_get_domain(dev, dev->of_node,
>> +                        DOMAIN_BUS_TI_SCI_INTA_MSI);
>> +    if (!dev->msi_domain) {
>> +        dev_err(dev, "Failed to get MSI domain\n");
>> +        return -EPROBE_DEFER;
>> +    }
>> +
>> +    ret = k3_ringacc_probe_dt(ringacc);
>> +    if (ret)
>> +        return ret;
>> +
>> +    res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rt");
>> +    base_rt = devm_ioremap_resource(dev, res);
>> +    if (IS_ERR(base_rt))
>> +        return PTR_ERR(base_rt);
>> +
>> +    res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fifos");
>> +    base_fifo = devm_ioremap_resource(dev, res);
>> +    if (IS_ERR(base_fifo))
>> +        return PTR_ERR(base_fifo);
>> +
>> +    res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>> "proxy_gcfg");
>> +    ringacc->proxy_gcfg = devm_ioremap_resource(dev, res);
>> +    if (IS_ERR(ringacc->proxy_gcfg))
>> +        return PTR_ERR(ringacc->proxy_gcfg);
>> +
>> +    res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>> +                       "proxy_target");
>> +    ringacc->proxy_target_base = devm_ioremap_resource(dev, res);
>> +    if (IS_ERR(ringacc->proxy_target_base))
>> +        return PTR_ERR(ringacc->proxy_target_base);
>> +
>> +    ringacc->num_proxies = dbg_readl(&ringacc->proxy_gcfg->config) &
>> +                     K3_RINGACC_PROXY_CFG_THREADS_MASK;
>> +
>> +    ringacc->rings = devm_kzalloc(dev,
>> +                      sizeof(*ringacc->rings) *
>> +                      ringacc->num_rings,
>> +                      GFP_KERNEL);
>> +    ringacc->rings_inuse = devm_kcalloc(dev,
>> +                        BITS_TO_LONGS(ringacc->num_rings),
>> +                        sizeof(unsigned long), GFP_KERNEL);
>> +    ringacc->proxy_inuse = devm_kcalloc(dev,
>> +                        BITS_TO_LONGS(ringacc->num_proxies),
>> +                        sizeof(unsigned long), GFP_KERNEL);
>> +
>> +    if (!ringacc->rings || !ringacc->rings_inuse ||
>> !ringacc->proxy_inuse)
>> +        return -ENOMEM;
>> +
>> +    for (i = 0; i < ringacc->num_rings; i++) {
>> +        ringacc->rings[i].rt = base_rt +
>> +                       K3_RINGACC_RT_REGS_STEP * i;
>> +        ringacc->rings[i].fifos = base_fifo +
>> +                      K3_RINGACC_FIFO_REGS_STEP * i;
>> +        ringacc->rings[i].parent = ringacc;
>> +        ringacc->rings[i].ring_id = i;
>> +        ringacc->rings[i].proxy_id = K3_RINGACC_PROXY_NOT_USED;
>> +    }
>> +    dev_set_drvdata(dev, ringacc);
>> +
>> +    ringacc->tisci_ring_ops = &ringacc->tisci->ops.rm_ring_ops;
>> +
>> +    pm_runtime_enable(dev);
>> +    ret = pm_runtime_get_sync(dev);
>> +    if (ret < 0) {
>> +        pm_runtime_put_noidle(dev);
>> +        dev_err(dev, "Failed to enable pm %d\n", ret);
>> +        goto err;
>> +    }
>> +
>> +    mutex_lock(&k3_ringacc_list_lock);
>> +    list_add_tail(&ringacc->list, &k3_ringacc_list);
>> +    mutex_unlock(&k3_ringacc_list_lock);
>> +
>> +    dev_info(dev, "Ring Accelerator probed rings:%u, gp-rings[%u,%u]
>> sci-dev-id:%u\n",
>> +         ringacc->num_rings,
>> +         ringacc->rm_gp_range->desc[0].start,
>> +         ringacc->rm_gp_range->desc[0].num,
>> +         ringacc->tisci_dev_id);
>> +    dev_info(dev, "dma-ring-reset-quirk: %s\n",
>> +         ringacc->dma_ring_reset_quirk ? "enabled" : "disabled");
>> +    dev_info(dev, "RA Proxy rev. %08x, num_proxies:%u\n",
>> +         dbg_readl(&ringacc->proxy_gcfg->revision),
>> +         ringacc->num_proxies);
>> +    return 0;
>> +
>> +err:
>> +    pm_runtime_disable(dev);
>> +    return ret;
>> +}
>> +
>> +static int k3_ringacc_remove(struct platform_device *pdev)
>> +{
>> +    struct k3_ringacc *ringacc = dev_get_drvdata(&pdev->dev);
>> +
>> +    pm_runtime_put_sync(&pdev->dev);
>> +    pm_runtime_disable(&pdev->dev);
>> +
>> +    mutex_lock(&k3_ringacc_list_lock);
>> +    list_del(&ringacc->list);
>> +    mutex_unlock(&k3_ringacc_list_lock);
>> +    return 0;
>> +}
>> +
>> +/* Match table for of_platform binding */
>> +static const struct of_device_id k3_ringacc_of_match[] = {
>> +    { .compatible = "ti,am654-navss-ringacc", },
>> +    {},
>> +};
>> +MODULE_DEVICE_TABLE(of, k3_ringacc_of_match);
>> +
>> +static struct platform_driver k3_ringacc_driver = {
>> +    .probe        = k3_ringacc_probe,
>> +    .remove        = k3_ringacc_remove,
>> +    .driver        = {
>> +        .name    = "k3-ringacc",
>> +        .of_match_table = k3_ringacc_of_match,
>> +    },
>> +};
>> +module_platform_driver(k3_ringacc_driver);
>> +
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_DESCRIPTION("TI Ringacc driver for K3 SOCs");
>> +MODULE_AUTHOR("Grygorii Strashko <grygorii.strashko@ti.com>");
>> diff --git a/include/linux/soc/ti/k3-ringacc.h
>> b/include/linux/soc/ti/k3-ringacc.h
>> new file mode 100644
>> index 000000000000..debffba48ac9
>> --- /dev/null
>> +++ b/include/linux/soc/ti/k3-ringacc.h
>> @@ -0,0 +1,262 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * K3 Ring Accelerator (RA) subsystem interface
>> + *
>> + * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
>> + */
>> +
>> +#ifndef __SOC_TI_K3_RINGACC_API_H_
>> +#define __SOC_TI_K3_RINGACC_API_H_
>> +
>> +#include <linux/types.h>
>> +
>> +struct device_node;
>> +
>> +/**
>> + * enum k3_ring_mode - &struct k3_ring_cfg mode
>> + *
>> + * RA ring operational modes
>> + *
>> + * @K3_RINGACC_RING_MODE_RING: Exposed Ring mode for SW direct access
>> + * @K3_RINGACC_RING_MODE_MESSAGE: Messaging mode. Messaging mode
>> requires
>> + *    that all accesses to the queue must go through this IP so that all
>> + *    accesses to the memory are controlled and ordered. This IP then
>> + *    controls the entire state of the queue, and SW has no directly
>> control,
>> + *    such as through doorbells and cannot access the storage memory
>> directly.
>> + *    This is particularly useful when more than one SW or HW entity
>> can be
>> + *    the producer and/or consumer at the same time
>> + * @K3_RINGACC_RING_MODE_CREDENTIALS: Credentials mode is message
>> mode plus
>> + *    stores credentials with each message, requiring the element
>> size to be
>> + *    doubled to fit the credentials. Any exposed memory should be
>> protected
>> + *    by a firewall from unwanted access
>> + * @K3_RINGACC_RING_MODE_QM:  Queue manager mode. This takes the
>> credentials
>> + *    mode and adds packet length per element, along with additional
>> read only
>> + *    fields for element count and accumulated queue length. The QM
>> mode only
>> + *    operates with an 8 byte element size (any other element size is
>> + *    illegal), and like in credentials mode each operation uses 2
>> element
>> + *    slots to store the credentials and length fields
>> + */
>> +enum k3_ring_mode {
>> +    K3_RINGACC_RING_MODE_RING = 0,
>> +    K3_RINGACC_RING_MODE_MESSAGE,
>> +    K3_RINGACC_RING_MODE_CREDENTIALS,
>> +    K3_RINGACC_RING_MODE_QM,
>> +    K3_RINGACC_RING_MODE_INVALID
>> +};
>> +
>> +/**
>> + * enum k3_ring_size - &struct k3_ring_cfg elm_size
>> + *
>> + * RA ring element's sizes in bytes.
>> + */
>> +enum k3_ring_size {
>> +    K3_RINGACC_RING_ELSIZE_4 = 0,
>> +    K3_RINGACC_RING_ELSIZE_8,
>> +    K3_RINGACC_RING_ELSIZE_16,
>> +    K3_RINGACC_RING_ELSIZE_32,
>> +    K3_RINGACC_RING_ELSIZE_64,
>> +    K3_RINGACC_RING_ELSIZE_128,
>> +    K3_RINGACC_RING_ELSIZE_256,
>> +    K3_RINGACC_RING_ELSIZE_INVALID
>> +};
>> +
>> +struct k3_ringacc;
>> +struct k3_ring;
>> +
>> +/**
>> + * enum k3_ring_cfg - RA ring configuration structure
>> + *
>> + * @size: Ring size, number of elements
>> + * @elm_size: Ring element size
>> + * @mode: Ring operational mode
>> + * @flags: Ring configuration flags. Possible values:
>> + *     @K3_RINGACC_RING_SHARED: when set allows to request the same ring
>> + *     few times. It's usable when the same ring is used as Free Host
>> PD ring
>> + *     for different flows, for example.
>> + *     Note: Locking should be done by consumer if required
>> + */
>> +struct k3_ring_cfg {
>> +    u32 size;
>> +    enum k3_ring_size elm_size;
>> +    enum k3_ring_mode mode;
>> +#define K3_RINGACC_RING_SHARED BIT(1)
>> +    u32 flags;
>> +};
>> +
>> +#define K3_RINGACC_RING_ID_ANY (-1)
>> +
>> +/**
>> + * of_k3_ringacc_get_by_phandle - find a RA by phandle property
>> + * @np: device node
>> + * @propname: property name containing phandle on RA node
>> + *
>> + * Returns pointer on the RA - struct k3_ringacc
>> + * or -ENODEV if not found,
>> + * or -EPROBE_DEFER if not yet registered
>> + */
>> +struct k3_ringacc *of_k3_ringacc_get_by_phandle(struct device_node *np,
>> +                        const char *property);
>> +
>> +#define K3_RINGACC_RING_USE_PROXY BIT(1)
>> +
>> +/**
>> + * k3_ringacc_request_ring - request ring from ringacc
>> + * @ringacc: pointer on ringacc
>> + * @id: ring id or K3_RINGACC_RING_ID_ANY for any general purpose ring
>> + * @flags:
>> + *    @K3_RINGACC_RING_USE_PROXY: if set - proxy will be allocated and
>> + *        used to access ring memory. Sopported only for rings in
>> + *        Message/Credentials/Queue mode.
>> + *
>> + * Returns pointer on the Ring - struct k3_ring
>> + * or NULL in case of failure.
>> + */
>> +struct k3_ring *k3_ringacc_request_ring(struct k3_ringacc *ringacc,
>> +                    int id, u32 flags);
>> +
>> +/**
>> + * k3_ringacc_ring_reset - ring reset
>> + * @ring: pointer on Ring
>> + *
>> + * Resets ring internal state ((hw)occ, (hw)idx).
>> + * TODO_GS: ? Ring can be reused without reconfiguration
>> + */
>> +void k3_ringacc_ring_reset(struct k3_ring *ring);
>> +/**
>> + * k3_ringacc_ring_reset - ring reset for DMA rings
>> + * @ring: pointer on Ring
>> + *
>> + * Resets ring internal state ((hw)occ, (hw)idx). Should be used for
>> rings
>> + * which are read by K3 UDMA, like TX or Free Host PD rings.
>> + */
>> +void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ);
>> +
>> +/**
>> + * k3_ringacc_ring_free - ring free
>> + * @ring: pointer on Ring
>> + *
>> + * Resets ring and free all alocated resources.
>> + */
>> +int k3_ringacc_ring_free(struct k3_ring *ring);
>> +
>> +/**
>> + * k3_ringacc_get_ring_id - Get the Ring ID
>> + * @ring: pointer on ring
>> + *
>> + * Returns the Ring ID
>> + */
>> +u32 k3_ringacc_get_ring_id(struct k3_ring *ring);
>> +
>> +/**
>> + * k3_ringacc_get_ring_irq_num - Get the irq number for the ring
>> + * @ring: pointer on ring
>> + *
>> + * Returns the interrupt number which can be used to request the
>> interrupt
>> + */
>> +int k3_ringacc_get_ring_irq_num(struct k3_ring *ring);
>> +
>> +/**
>> + * k3_ringacc_ring_cfg - ring configure
>> + * @ring: pointer on ring
>> + * @cfg: Ring configuration parameters (see &struct k3_ring_cfg)
>> + *
>> + * Configures ring, including ring memory allocation.
>> + * Returns 0 on success, errno otherwise.
>> + */
>> +int k3_ringacc_ring_cfg(struct k3_ring *ring, struct k3_ring_cfg *cfg);
>> +
>> +/**
>> + * k3_ringacc_ring_get_size - get ring size
>> + * @ring: pointer on ring
>> + *
>> + * Returns ring size in number of elements.
>> + */
>> +u32 k3_ringacc_ring_get_size(struct k3_ring *ring);
>> +
>> +/**
>> + * k3_ringacc_ring_get_free - get free elements
>> + * @ring: pointer on ring
>> + *
>> + * Returns number of free elements in the ring.
>> + */
>> +u32 k3_ringacc_ring_get_free(struct k3_ring *ring);
>> +
>> +/**
>> + * k3_ringacc_ring_get_occ - get ring occupancy
>> + * @ring: pointer on ring
>> + *
>> + * Returns total number of valid entries on the ring
>> + */
>> +u32 k3_ringacc_ring_get_occ(struct k3_ring *ring);
>> +
>> +/**
>> + * k3_ringacc_ring_is_full - checks if ring is full
>> + * @ring: pointer on ring
>> + *
>> + * Returns true if the ring is full
>> + */
>> +u32 k3_ringacc_ring_is_full(struct k3_ring *ring);
>> +
>> +/**
>> + * k3_ringacc_ring_push - push element to the ring tail
>> + * @ring: pointer on ring
>> + * @elem: pointer on ring element buffer
>> + *
>> + * Push one ring element to the ring tail. Size of the ring element is
>> + * determined by ring configuration &struct k3_ring_cfg elm_size.
>> + *
>> + * Returns 0 on success, errno otherwise.
>> + */
>> +int k3_ringacc_ring_push(struct k3_ring *ring, void *elem);
>> +
>> +/**
>> + * k3_ringacc_ring_pop - pop element from the ring head
>> + * @ring: pointer on ring
>> + * @elem: pointer on ring element buffer
>> + *
>> + * Push one ring element from the ring head. Size of the ring element is
>> + * determined by ring configuration &struct k3_ring_cfg elm_size..
>> + *
>> + * Returns 0 on success, errno otherwise.
>> + */
>> +int k3_ringacc_ring_pop(struct k3_ring *ring, void *elem);
>> +
>> +/**
>> + * k3_ringacc_ring_push_head - push element to the ring head
>> + * @ring: pointer on ring
>> + * @elem: pointer on ring element buffer
>> + *
>> + * Push one ring element to the ring head. Size of the ring element is
>> + * determined by ring configuration &struct k3_ring_cfg elm_size.
>> + *
>> + * Returns 0 on success, errno otherwise.
>> + * Not Supported by ring modes: K3_RINGACC_RING_MODE_RING
>> + */
>> +int k3_ringacc_ring_push_head(struct k3_ring *ring, void *elem);
>> +
>> +/**
>> + * k3_ringacc_ring_pop_tail - pop element from the ring tail
>> + * @ring: pointer on ring
>> + * @elem: pointer on ring element buffer
>> + *
>> + * Push one ring element from the ring tail. Size of the ring element is
>> + * determined by ring configuration &struct k3_ring_cfg elm_size.
>> + *
>> + * Returns 0 on success, errno otherwise.
>> + * Not Supported by ring modes: K3_RINGACC_RING_MODE_RING
>> + */
>> +int k3_ringacc_ring_pop_tail(struct k3_ring *ring, void *elem);
>> +
>> +u32 k3_ringacc_get_tisci_dev_id(struct k3_ring *ring);
>> +
>> +/**
>> + * Debugging definitions
>> + * TODO: might be removed
>> + */
>> +#ifdef CONFIG_TI_K3_RINGACC_DEBUG
>> +void k3_ringacc_ring_dump(struct k3_ring *ring);
>> +#else
>> +static inline void k3_ringacc_ring_dump(struct k3_ring *ring) {};
>> +#endif
>> +
>> +#endif /* __SOC_TI_K3_RINGACC_API_H_ */
>>
> 
> -- 
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> Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
> 
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Peter Ujfalusi Sept. 9, 2019, 1 p.m. UTC | #4
Hi,

Grygorii, can you take a look?

On 09/09/2019 9.09, Tero Kristo wrote:
> Hi,
> 
> Mostly some cosmetic comments below, other than that seems fine to me.
> 
> On 30/07/2019 12:34, Peter Ujfalusi wrote:
>> From: Grygorii Strashko <grygorii.strashko@ti.com>
>>
>> The Ring Accelerator (RINGACC or RA) provides hardware acceleration to
>> enable straightforward passing of work between a producer and a consumer.
>> There is one RINGACC module per NAVSS on TI AM65x SoCs.
>>
>> The RINGACC converts constant-address read and write accesses to
>> equivalent
>> read or write accesses to a circular data structure in memory. The
>> RINGACC
>> eliminates the need for each DMA controller which needs to access ring
>> elements from having to know the current state of the ring (base address,
>> current offset). The DMA controller performs a read or write access to a
>> specific address range (which maps to the source interface on the
>> RINGACC)
>> and the RINGACC replaces the address for the transaction with a new
>> address
>> which corresponds to the head or tail element of the ring (head for
>> reads,
>> tail for writes). Since the RINGACC maintains the state, multiple DMA
>> controllers or channels are allowed to coherently share the same rings as
>> applicable. The RINGACC is able to place data which is destined towards
>> software into cached memory directly.
>>
>> Supported ring modes:
>> - Ring Mode
>> - Messaging Mode
>> - Credentials Mode
>> - Queue Manager Mode
>>
>> TI-SCI integration:
>>
>> Texas Instrument's System Control Interface (TI-SCI) Message Protocol now
>> has control over Ringacc module resources management (RM) and Rings
>> configuration.
>>
>> The corresponding support of TI-SCI Ringacc module RM protocol
>> introduced as option through DT parameters:
>> - ti,sci: phandle on TI-SCI firmware controller DT node
>> - ti,sci-dev-id: TI-SCI device identifier as per TI-SCI firmware spec
>>
>> if both parameters present - Ringacc driver will configure/free/reset
>> Rings
>> using TI-SCI Message Ringacc RM Protocol.
>>
>> The Ringacc driver manages Rings allocation by itself now and requests
>> TI-SCI firmware to allocate and configure specific Rings only. It's done
>> this way because, Linux driver implements two stage Rings allocation and
>> configuration (allocate ring and configure ring) while I-SCI Message
> 
> I-SCI should be TI-SCI I believe.

Yes, it supposed to be.

> 
>> Protocol supports only one combined operation (allocate+configure).
>>
>> Grygorii Strashko <grygorii.strashko@ti.com>
> 
> Above seems to be missing SoB?

Oh, it is really missing.

> 
>> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
>> ---
>>   drivers/soc/ti/Kconfig            |   17 +
>>   drivers/soc/ti/Makefile           |    1 +
>>   drivers/soc/ti/k3-ringacc.c       | 1191 +++++++++++++++++++++++++++++
>>   include/linux/soc/ti/k3-ringacc.h |  262 +++++++
>>   4 files changed, 1471 insertions(+)
>>   create mode 100644 drivers/soc/ti/k3-ringacc.c
>>   create mode 100644 include/linux/soc/ti/k3-ringacc.h
>>
>> diff --git a/drivers/soc/ti/Kconfig b/drivers/soc/ti/Kconfig
>> index cf545f428d03..10c76faa503e 100644
>> --- a/drivers/soc/ti/Kconfig
>> +++ b/drivers/soc/ti/Kconfig
>> @@ -80,6 +80,23 @@ config TI_SCI_PM_DOMAINS
>>         called ti_sci_pm_domains. Note this is needed early in boot
>> before
>>         rootfs may be available.
>>   +config TI_K3_RINGACC
>> +    tristate "K3 Ring accelerator Sub System"
>> +    depends on ARCH_K3 || COMPILE_TEST
>> +    depends on TI_SCI_INTA_IRQCHIP
>> +    default y
>> +    help
>> +      Say y here to support the K3 Ring accelerator module.
>> +      The Ring Accelerator (RINGACC or RA)  provides hardware
>> acceleration
>> +      to enable straightforward passing of work between a producer
>> +      and a consumer. There is one RINGACC module per NAVSS on TI
>> AM65x SoCs
>> +      If unsure, say N.
>> +
>> +config TI_K3_RINGACC_DEBUG
>> +    tristate "K3 Ring accelerator Sub System tests and debug"
>> +    depends on TI_K3_RINGACC
>> +    default n
>> +
>>   endif # SOC_TI
>>     config TI_SCI_INTA_MSI_DOMAIN
>> diff --git a/drivers/soc/ti/Makefile b/drivers/soc/ti/Makefile
>> index b3868d392d4f..cc4bc8b08bf5 100644
>> --- a/drivers/soc/ti/Makefile
>> +++ b/drivers/soc/ti/Makefile
>> @@ -9,3 +9,4 @@ obj-$(CONFIG_AMX3_PM)            += pm33xx.o
>>   obj-$(CONFIG_WKUP_M3_IPC)        += wkup_m3_ipc.o
>>   obj-$(CONFIG_TI_SCI_PM_DOMAINS)        += ti_sci_pm_domains.o
>>   obj-$(CONFIG_TI_SCI_INTA_MSI_DOMAIN)    += ti_sci_inta_msi.o
>> +obj-$(CONFIG_TI_K3_RINGACC)        += k3-ringacc.o
>> diff --git a/drivers/soc/ti/k3-ringacc.c b/drivers/soc/ti/k3-ringacc.c
>> new file mode 100644
>> index 000000000000..401dfc963319
>> --- /dev/null
>> +++ b/drivers/soc/ti/k3-ringacc.c
>> @@ -0,0 +1,1191 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * TI K3 NAVSS Ring Accelerator subsystem driver
>> + *
>> + * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
>> + */
>> +
>> +#include <linux/dma-mapping.h>
>> +#include <linux/io.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/pm_runtime.h>
>> +#include <linux/soc/ti/k3-ringacc.h>
>> +#include <linux/soc/ti/ti_sci_protocol.h>
>> +#include <linux/soc/ti/ti_sci_inta_msi.h>
>> +#include <linux/of_irq.h>
>> +#include <linux/irqdomain.h>
>> +
>> +static LIST_HEAD(k3_ringacc_list);
>> +static DEFINE_MUTEX(k3_ringacc_list_lock);
>> +
>> +#ifdef CONFIG_TI_K3_RINGACC_DEBUG
>> +#define    k3_nav_dbg(dev, arg...) dev_err(dev, arg)
> 
> dev_err seems exaggeration for debug purposes, maybe just dev_info.
> 
>> +static    void dbg_writel(u32 v, void __iomem *reg)
>> +{
>> +    pr_err("WRITEL(32): v(%08X)-->reg(%p)\n", v, reg);
> 
> Again, maybe just pr_info.

I think I'll just drop CONFIG_TI_K3_RINGACC_DEBUG altogether along with
dbg_writel/dbg_readl/k3_nav_dbg and use dev_dbg() when appropriate.

> 
>> +    writel(v, reg);
>> +}
>> +
>> +static    u32 dbg_readl(void __iomem *reg)
>> +{
>> +    u32 v;
>> +
>> +    v = readl(reg);
>> +    pr_err("READL(32): v(%08X)<--reg(%p)\n", v, reg);
>> +    return v;
>> +}
>> +#else
>> +#define    k3_nav_dbg(dev, arg...) dev_dbg(dev, arg)
>> +#define dbg_writel(v, reg) writel(v, reg)
> 
> Do you need to use hard writel, writel_relaxed is not enough?

not sure if we really need the barriers, but __raw_writel() should be
fine here imho

>> +
>> +#define dbg_readl(reg) readl(reg)
> 
> Same as above but for read?

__raw_readl() could be fine in also.

...

>> +/**
>> + * struct k3_ringacc - Rings accelerator descriptor
>> + *
>> + * @dev - pointer on RA device
>> + * @proxy_gcfg - RA proxy global config registers
>> + * @proxy_target_base - RA proxy datapath region
>> + * @num_rings - number of ring in RA
>> + * @rm_gp_range - general purpose rings range from tisci
>> + * @dma_ring_reset_quirk - DMA reset w/a enable
>> + * @num_proxies - number of RA proxies
>> + * @rings - array of rings descriptors (struct @k3_ring)
>> + * @list - list of RAs in the system
>> + * @tisci - pointer ti-sci handle
>> + * @tisci_ring_ops - ti-sci rings ops
>> + * @tisci_dev_id - ti-sci device id
>> + */
>> +struct k3_ringacc {
>> +    struct device *dev;
>> +    struct k3_ringacc_proxy_gcfg_regs __iomem *proxy_gcfg;
>> +    void __iomem *proxy_target_base;
>> +    u32 num_rings; /* number of rings in Ringacc module */
>> +    unsigned long *rings_inuse;
>> +    struct ti_sci_resource *rm_gp_range;
>> +
>> +    bool dma_ring_reset_quirk;
>> +    u32 num_proxies;
>> +    unsigned long *proxy_inuse;
> 
> proxy_inuse is not documented above.

I see, I'll update the documentation.

>> +
>> +    struct k3_ring *rings;
>> +    struct list_head list;
>> +    struct mutex req_lock; /* protect rings allocation */
>> +
>> +    const struct ti_sci_handle *tisci;
>> +    const struct ti_sci_rm_ringacc_ops *tisci_ring_ops;
>> +    u32  tisci_dev_id;
>> +};
>> +
>> +static long k3_ringacc_ring_get_fifo_pos(struct k3_ring *ring)
>> +{
>> +    return K3_RINGACC_FIFO_WINDOW_SIZE_BYTES -
>> +           (4 << ring->elm_size);
>> +}
>> +
>> +static void *k3_ringacc_get_elm_addr(struct k3_ring *ring, u32 idx)
>> +{
>> +    return (idx * (4 << ring->elm_size) + ring->ring_mem_virt);
> 
> The arithmetic here seems backwards compared to most other code I've
> seen. It would be more readable if you have it like:
> 
> ring->ring_mem_virt + idx * (4 << ring->elm_size);

Yes, I'll update.

> 
>> +}
>> +
>> +static int k3_ringacc_ring_push_mem(struct k3_ring *ring, void *elem);
>> +static int k3_ringacc_ring_pop_mem(struct k3_ring *ring, void *elem);
>> +
>> +static struct k3_ring_ops k3_ring_mode_ring_ops = {
>> +        .push_tail = k3_ringacc_ring_push_mem,
>> +        .pop_head = k3_ringacc_ring_pop_mem,
>> +};
>> +
>> +static int k3_ringacc_ring_push_io(struct k3_ring *ring, void *elem);
>> +static int k3_ringacc_ring_pop_io(struct k3_ring *ring, void *elem);
>> +static int k3_ringacc_ring_push_head_io(struct k3_ring *ring, void
>> *elem);
>> +static int k3_ringacc_ring_pop_tail_io(struct k3_ring *ring, void
>> *elem);
>> +
>> +static struct k3_ring_ops k3_ring_mode_msg_ops = {
>> +        .push_tail = k3_ringacc_ring_push_io,
>> +        .push_head = k3_ringacc_ring_push_head_io,
>> +        .pop_tail = k3_ringacc_ring_pop_tail_io,
>> +        .pop_head = k3_ringacc_ring_pop_io,
>> +};
>> +
>> +static int k3_ringacc_ring_push_head_proxy(struct k3_ring *ring, void
>> *elem);
>> +static int k3_ringacc_ring_push_tail_proxy(struct k3_ring *ring, void
>> *elem);
>> +static int k3_ringacc_ring_pop_head_proxy(struct k3_ring *ring, void
>> *elem);
>> +static int k3_ringacc_ring_pop_tail_proxy(struct k3_ring *ring, void
>> *elem);
>> +
>> +static struct k3_ring_ops k3_ring_mode_proxy_ops = {
>> +        .push_tail = k3_ringacc_ring_push_tail_proxy,
>> +        .push_head = k3_ringacc_ring_push_head_proxy,
>> +        .pop_tail = k3_ringacc_ring_pop_tail_proxy,
>> +        .pop_head = k3_ringacc_ring_pop_head_proxy,
>> +};
>> +
>> +#ifdef CONFIG_TI_K3_RINGACC_DEBUG
>> +void k3_ringacc_ring_dump(struct k3_ring *ring)
>> +{
>> +    struct device *dev = ring->parent->dev;
>> +
>> +    k3_nav_dbg(dev, "dump ring: %d\n", ring->ring_id);
>> +    k3_nav_dbg(dev, "dump mem virt %p, dma %pad\n",
>> +           ring->ring_mem_virt, &ring->ring_mem_dma);
>> +    k3_nav_dbg(dev, "dump elmsize %d, size %d, mode %d, proxy_id %d\n",
>> +           ring->elm_size, ring->size, ring->mode, ring->proxy_id);
>> +
>> +    k3_nav_dbg(dev, "dump ring_rt_regs: db%08x\n",
>> +           readl(&ring->rt->db));
> 
> Why not use readl_relaxed in this func?

__raw_readl() might be enough?

> 
>> +    k3_nav_dbg(dev, "dump occ%08x\n",
>> +           readl(&ring->rt->occ));
>> +    k3_nav_dbg(dev, "dump indx%08x\n",
>> +           readl(&ring->rt->indx));
>> +    k3_nav_dbg(dev, "dump hwocc%08x\n",
>> +           readl(&ring->rt->hwocc));
>> +    k3_nav_dbg(dev, "dump hwindx%08x\n",
>> +           readl(&ring->rt->hwindx));
>> +
>> +    if (ring->ring_mem_virt)
>> +        print_hex_dump(KERN_ERR, "dump ring_mem_virt ",
>> +                   DUMP_PREFIX_NONE, 16, 1,
>> +                   ring->ring_mem_virt, 16 * 8, false);
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_dump);
> 
> Do you really need to export a debug function?

It might come helpful for clients to dump the ring status runtime, but
since we don't have users, I'll move it to static.

>> +#endif
>> +
>> +struct k3_ring *k3_ringacc_request_ring(struct k3_ringacc *ringacc,
>> +                    int id, u32 flags)
>> +{
>> +    int proxy_id = K3_RINGACC_PROXY_NOT_USED;
>> +
>> +    mutex_lock(&ringacc->req_lock);
>> +
>> +    if (id == K3_RINGACC_RING_ID_ANY) {
>> +        /* Request for any general purpose ring */
>> +        struct ti_sci_resource_desc *gp_rings =
>> +                        &ringacc->rm_gp_range->desc[0];
>> +        unsigned long size;
>> +
>> +        size = gp_rings->start + gp_rings->num;
>> +        id = find_next_zero_bit(ringacc->rings_inuse, size,
>> +                    gp_rings->start);
>> +        if (id == size)
>> +            goto error;
>> +    } else if (id < 0) {
>> +        goto error;
>> +    }
>> +
>> +    if (test_bit(id, ringacc->rings_inuse) &&
>> +        !(ringacc->rings[id].flags & K3_RING_FLAG_SHARED))
>> +        goto error;
>> +    else if (ringacc->rings[id].flags & K3_RING_FLAG_SHARED)
>> +        goto out;
>> +
>> +    if (flags & K3_RINGACC_RING_USE_PROXY) {
>> +        proxy_id = find_next_zero_bit(ringacc->proxy_inuse,
>> +                          ringacc->num_proxies, 0);
>> +        if (proxy_id == ringacc->num_proxies)
>> +            goto error;
>> +    }
>> +
>> +    if (!try_module_get(ringacc->dev->driver->owner))
>> +        goto error;
>> +
>> +    if (proxy_id != K3_RINGACC_PROXY_NOT_USED) {
>> +        set_bit(proxy_id, ringacc->proxy_inuse);
>> +        ringacc->rings[id].proxy_id = proxy_id;
>> +        k3_nav_dbg(ringacc->dev, "Giving ring#%d proxy#%d\n",
>> +               id, proxy_id);
>> +    } else {
>> +        k3_nav_dbg(ringacc->dev, "Giving ring#%d\n", id);
>> +    }
>> +
>> +    set_bit(id, ringacc->rings_inuse);
>> +out:
>> +    ringacc->rings[id].use_count++;
>> +    mutex_unlock(&ringacc->req_lock);
>> +    return &ringacc->rings[id];
>> +
>> +error:
>> +    mutex_unlock(&ringacc->req_lock);
>> +    return NULL;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_request_ring);
>> +
>> +static void k3_ringacc_ring_reset_sci(struct k3_ring *ring)
>> +{
>> +    struct k3_ringacc *ringacc = ring->parent;
>> +    int ret;
>> +
>> +    ret = ringacc->tisci_ring_ops->config(
>> +            ringacc->tisci,
>> +            TI_SCI_MSG_VALUE_RM_RING_COUNT_VALID,
>> +            ringacc->tisci_dev_id,
>> +            ring->ring_id,
>> +            0,
>> +            0,
>> +            ring->size,
>> +            0,
>> +            0,
>> +            0);
>> +    if (ret)
>> +        dev_err(ringacc->dev, "TISCI reset ring fail (%d) ring_idx
>> %d\n",
>> +            ret, ring->ring_id);
> 
> Return value of sci ops is masked, why not return it and let the caller
> handle it properly?
> 
> Same comment for anything similar that follows.

Hrm, there is not much a caller can do other than PANIC in case the ring
configuration fails.
I can probagate the error, but not sure what action can be taken, if any.

>> +}
>> +
>> +void k3_ringacc_ring_reset(struct k3_ring *ring)
>> +{
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return;
>> +
>> +    ring->occ = 0;
>> +    ring->free = 0;
>> +    ring->rindex = 0;
>> +    ring->windex = 0;
>> +
>> +    k3_ringacc_ring_reset_sci(ring);
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset);
>> +
>> +static void k3_ringacc_ring_reconfig_qmode_sci(struct k3_ring *ring,
>> +                           enum k3_ring_mode mode)
>> +{
>> +    struct k3_ringacc *ringacc = ring->parent;
>> +    int ret;
>> +
>> +    ret = ringacc->tisci_ring_ops->config(
>> +            ringacc->tisci,
>> +            TI_SCI_MSG_VALUE_RM_RING_MODE_VALID,
>> +            ringacc->tisci_dev_id,
>> +            ring->ring_id,
>> +            0,
>> +            0,
>> +            0,
>> +            mode,
>> +            0,
>> +            0);
>> +    if (ret)
>> +        dev_err(ringacc->dev, "TISCI reconf qmode fail (%d) ring_idx
>> %d\n",
>> +            ret, ring->ring_id);
>> +}
>> +
>> +void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ)
>> +{
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return;
>> +
>> +    if (!ring->parent->dma_ring_reset_quirk)
>> +        return;
>> +
>> +    if (!occ)
>> +        occ = dbg_readl(&ring->rt->occ);
>> +
>> +    if (occ) {
>> +        u32 db_ring_cnt, db_ring_cnt_cur;
>> +
>> +        k3_nav_dbg(ring->parent->dev, "%s %u occ: %u\n", __func__,
>> +               ring->ring_id, occ);
>> +        /* 2. Reset the ring */
> 
> 2? Where is 1?

Oh, I'll fix the numbering.

> 
>> +        k3_ringacc_ring_reset_sci(ring);
>> +
>> +        /*
>> +         * 3. Setup the ring in ring/doorbell mode
>> +         * (if not already in this mode)
>> +         */
>> +        if (ring->mode != K3_RINGACC_RING_MODE_RING)
>> +            k3_ringacc_ring_reconfig_qmode_sci(
>> +                    ring, K3_RINGACC_RING_MODE_RING);
>> +        /*
>> +         * 4. Ring the doorbell 2**22 – ringOcc times.
>> +         * This will wrap the internal UDMAP ring state occupancy
>> +         * counter (which is 21-bits wide) to 0.
>> +         */
>> +        db_ring_cnt = (1U << 22) - occ;
>> +
>> +        while (db_ring_cnt != 0) {
>> +            /*
>> +             * Ring the doorbell with the maximum count each
>> +             * iteration if possible to minimize the total
>> +             * of writes
>> +             */
>> +            if (db_ring_cnt > K3_RINGACC_MAX_DB_RING_CNT)
>> +                db_ring_cnt_cur = K3_RINGACC_MAX_DB_RING_CNT;
>> +            else
>> +                db_ring_cnt_cur = db_ring_cnt;
>> +
>> +            writel(db_ring_cnt_cur, &ring->rt->db);
>> +            db_ring_cnt -= db_ring_cnt_cur;
>> +        }
>> +
>> +        /* 5. Restore the original ring mode (if not ring mode) */
>> +        if (ring->mode != K3_RINGACC_RING_MODE_RING)
>> +            k3_ringacc_ring_reconfig_qmode_sci(ring, ring->mode);
>> +    }
>> +
>> +    /* 2. Reset the ring */
> 
> Again 2?

I'll drop the '2.'

> 
>> +    k3_ringacc_ring_reset(ring);
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset_dma);
>> +
>> +static void k3_ringacc_ring_free_sci(struct k3_ring *ring)
>> +{
>> +    struct k3_ringacc *ringacc = ring->parent;
>> +    int ret;
>> +
>> +    ret = ringacc->tisci_ring_ops->config(
>> +            ringacc->tisci,
>> +            TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
>> +            ringacc->tisci_dev_id,
>> +            ring->ring_id,
>> +            0,
>> +            0,
>> +            0,
>> +            0,
>> +            0,
>> +            0);
>> +    if (ret)
>> +        dev_err(ringacc->dev, "TISCI ring free fail (%d) ring_idx %d\n",
>> +            ret, ring->ring_id);
>> +}
>> +
>> +int k3_ringacc_ring_free(struct k3_ring *ring)
>> +{
>> +    struct k3_ringacc *ringacc;
>> +
>> +    if (!ring)
>> +        return -EINVAL;
>> +
>> +    ringacc = ring->parent;
>> +
>> +    k3_nav_dbg(ring->parent->dev, "flags: 0x%08x\n", ring->flags);
>> +
>> +    if (!test_bit(ring->ring_id, ringacc->rings_inuse))
>> +        return -EINVAL;
>> +
>> +    mutex_lock(&ringacc->req_lock);
>> +
>> +    if (--ring->use_count)
>> +        goto out;
>> +
>> +    if (!(ring->flags & K3_RING_FLAG_BUSY))
>> +        goto no_init;
>> +
>> +    k3_ringacc_ring_free_sci(ring);
>> +
>> +    dma_free_coherent(ringacc->dev,
>> +              ring->size * (4 << ring->elm_size),
>> +              ring->ring_mem_virt, ring->ring_mem_dma);
>> +    ring->flags = 0;
>> +    ring->ops = NULL;
>> +    if (ring->proxy_id != K3_RINGACC_PROXY_NOT_USED) {
>> +        clear_bit(ring->proxy_id, ringacc->proxy_inuse);
>> +        ring->proxy = NULL;
>> +        ring->proxy_id = K3_RINGACC_PROXY_NOT_USED;
>> +    }
>> +
>> +no_init:
>> +    clear_bit(ring->ring_id, ringacc->rings_inuse);
>> +
>> +    module_put(ringacc->dev->driver->owner);
>> +
>> +out:
>> +    mutex_unlock(&ringacc->req_lock);
>> +    return 0;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_free);
>> +
>> +u32 k3_ringacc_get_ring_id(struct k3_ring *ring)
>> +{
>> +    if (!ring)
>> +        return -EINVAL;
>> +
>> +    return ring->ring_id;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_id);
>> +
>> +u32 k3_ringacc_get_tisci_dev_id(struct k3_ring *ring)
>> +{
>> +    if (!ring)
>> +        return -EINVAL;
>> +
> 
> What if parent is NULL? Can it ever be here?

No, parent can not be NULL as the client would not have the ring in the
first place.

> 
>> +    return ring->parent->tisci_dev_id;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_get_tisci_dev_id);
>> +
>> +int k3_ringacc_get_ring_irq_num(struct k3_ring *ring)
>> +{
>> +    int irq_num;
>> +
>> +    if (!ring)
>> +        return -EINVAL;
>> +
>> +    irq_num = ti_sci_inta_msi_get_virq(ring->parent->dev,
>> ring->ring_id);
>> +    if (irq_num <= 0)
>> +        irq_num = -EINVAL;
>> +    return irq_num;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_irq_num);
>> +
>> +static int k3_ringacc_ring_cfg_sci(struct k3_ring *ring)
>> +{
>> +    struct k3_ringacc *ringacc = ring->parent;
>> +    u32 ring_idx;
>> +    int ret;
>> +
>> +    if (!ringacc->tisci)
>> +        return -EINVAL;
>> +
>> +    ring_idx = ring->ring_id;
>> +    ret = ringacc->tisci_ring_ops->config(
>> +            ringacc->tisci,
>> +            TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
>> +            ringacc->tisci_dev_id,
>> +            ring_idx,
>> +            lower_32_bits(ring->ring_mem_dma),
>> +            upper_32_bits(ring->ring_mem_dma),
>> +            ring->size,
>> +            ring->mode,
>> +            ring->elm_size,
>> +            0);
>> +    if (ret)
>> +        dev_err(ringacc->dev, "TISCI config ring fail (%d) ring_idx
>> %d\n",
>> +            ret, ring_idx);
>> +
>> +    return ret;
>> +}
>> +
>> +int k3_ringacc_ring_cfg(struct k3_ring *ring, struct k3_ring_cfg *cfg)
>> +{
>> +    struct k3_ringacc *ringacc = ring->parent;
>> +    int ret = 0;
>> +
>> +    if (!ring || !cfg)
>> +        return -EINVAL;
>> +    if (cfg->elm_size > K3_RINGACC_RING_ELSIZE_256 ||
>> +        cfg->mode > K3_RINGACC_RING_MODE_QM ||
>> +        cfg->size & ~K3_RINGACC_CFG_RING_SIZE_ELCNT_MASK ||
>> +        !test_bit(ring->ring_id, ringacc->rings_inuse))
>> +        return -EINVAL;
>> +
>> +    if (ring->use_count != 1)
> 
> Hmm, isn't this a failure actually?

Yes, it is: -EBUSY

>> +        return 0;
>> +
>> +    ring->size = cfg->size;
>> +    ring->elm_size = cfg->elm_size;
>> +    ring->mode = cfg->mode;
>> +    ring->occ = 0;
>> +    ring->free = 0;
>> +    ring->rindex = 0;
>> +    ring->windex = 0;
>> +
>> +    if (ring->proxy_id != K3_RINGACC_PROXY_NOT_USED)
>> +        ring->proxy = ringacc->proxy_target_base +
>> +                  ring->proxy_id * K3_RINGACC_PROXY_TARGET_STEP;
>> +
>> +    switch (ring->mode) {
>> +    case K3_RINGACC_RING_MODE_RING:
>> +        ring->ops = &k3_ring_mode_ring_ops;
>> +        break;
>> +    case K3_RINGACC_RING_MODE_QM:
>> +        /*
>> +         * In Queue mode elm_size can be 8 only and each operation
>> +         * uses 2 element slots
>> +         */
>> +        if (cfg->elm_size != K3_RINGACC_RING_ELSIZE_8 ||
>> +            cfg->size % 2)
>> +            goto err_free_proxy;
>> +        /* else, fall through */
>> +    case K3_RINGACC_RING_MODE_MESSAGE:
>> +        if (ring->proxy)
>> +            ring->ops = &k3_ring_mode_proxy_ops;
>> +        else
>> +            ring->ops = &k3_ring_mode_msg_ops;
>> +        break;
>> +    default:
>> +        ring->ops = NULL;
>> +        ret = -EINVAL;
>> +        goto err_free_proxy;
>> +    };
>> +
>> +    ring->ring_mem_virt =
>> +            dma_alloc_coherent(ringacc->dev,
>> +                       ring->size * (4 << ring->elm_size),
>> +                       &ring->ring_mem_dma, GFP_KERNEL);
>> +    if (!ring->ring_mem_virt) {
>> +        dev_err(ringacc->dev, "Failed to alloc ring mem\n");
>> +        ret = -ENOMEM;
>> +        goto err_free_ops;
>> +    }
>> +
>> +    ret = k3_ringacc_ring_cfg_sci(ring);
>> +
>> +    if (ret)
>> +        goto err_free_mem;
>> +
>> +    ring->flags |= K3_RING_FLAG_BUSY;
>> +    ring->flags |= (cfg->flags & K3_RINGACC_RING_SHARED) ?
>> +            K3_RING_FLAG_SHARED : 0;
>> +
>> +    k3_ringacc_ring_dump(ring);
>> +
>> +    return 0;
>> +
>> +err_free_mem:
>> +    dma_free_coherent(ringacc->dev,
>> +              ring->size * (4 << ring->elm_size),
>> +              ring->ring_mem_virt,
>> +              ring->ring_mem_dma);
>> +err_free_ops:
>> +    ring->ops = NULL;
>> +err_free_proxy:
>> +    ring->proxy = NULL;
>> +    return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_cfg);
>> +
>> +u32 k3_ringacc_ring_get_size(struct k3_ring *ring)
>> +{
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return -EINVAL;
>> +
>> +    return ring->size;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_size);
>> +
>> +u32 k3_ringacc_ring_get_free(struct k3_ring *ring)
>> +{
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return -EINVAL;
>> +
>> +    if (!ring->free)
>> +        ring->free = ring->size - dbg_readl(&ring->rt->occ);
>> +
>> +    return ring->free;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_free);
>> +
>> +u32 k3_ringacc_ring_get_occ(struct k3_ring *ring)
>> +{
>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>> +        return -EINVAL;
>> +
>> +    return dbg_readl(&ring->rt->occ);
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_occ);
>> +
>> +u32 k3_ringacc_ring_is_full(struct k3_ring *ring)
>> +{
>> +    return !k3_ringacc_ring_get_free(ring);
>> +}
>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_is_full);
>> +
>> +enum k3_ringacc_access_mode {
>> +    K3_RINGACC_ACCESS_MODE_PUSH_HEAD,
>> +    K3_RINGACC_ACCESS_MODE_POP_HEAD,
>> +    K3_RINGACC_ACCESS_MODE_PUSH_TAIL,
>> +    K3_RINGACC_ACCESS_MODE_POP_TAIL,
>> +    K3_RINGACC_ACCESS_MODE_PEEK_HEAD,
>> +    K3_RINGACC_ACCESS_MODE_PEEK_TAIL,
>> +};
>> +
>> +static int k3_ringacc_ring_cfg_proxy(struct k3_ring *ring,
>> +                     enum k3_ringacc_proxy_access_mode mode)
>> +{
>> +    u32 val;
>> +
>> +    val = ring->ring_id;
>> +    val |= mode << 16;
>> +    val |= ring->elm_size << 24;
> 
> Would be nice to have these magic shifts as defines.

OK, I'll add defines for the magic shifts.

> 
>> +    dbg_writel(val, &ring->proxy->control);
>> +    return 0;
>> +}
>> +

Thanks for the review,
- Péter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
Grygorii Strashko Sept. 9, 2019, 4:58 p.m. UTC | #5
On 09/09/2019 16:00, Peter Ujfalusi wrote:
> Hi,
> 
> Grygorii, can you take a look?
> 
> On 09/09/2019 9.09, Tero Kristo wrote:
>> Hi,
>>
>> Mostly some cosmetic comments below, other than that seems fine to me.
>>
>> On 30/07/2019 12:34, Peter Ujfalusi wrote:
>>> From: Grygorii Strashko <grygorii.strashko@ti.com>
>>>
>>> The Ring Accelerator (RINGACC or RA) provides hardware acceleration to
>>> enable straightforward passing of work between a producer and a consumer.
>>> There is one RINGACC module per NAVSS on TI AM65x SoCs.
>>>
>>> The RINGACC converts constant-address read and write accesses to
>>> equivalent
>>> read or write accesses to a circular data structure in memory. The
>>> RINGACC
>>> eliminates the need for each DMA controller which needs to access ring
>>> elements from having to know the current state of the ring (base address,
>>> current offset). The DMA controller performs a read or write access to a
>>> specific address range (which maps to the source interface on the
>>> RINGACC)
>>> and the RINGACC replaces the address for the transaction with a new
>>> address
>>> which corresponds to the head or tail element of the ring (head for
>>> reads,
>>> tail for writes). Since the RINGACC maintains the state, multiple DMA
>>> controllers or channels are allowed to coherently share the same rings as
>>> applicable. The RINGACC is able to place data which is destined towards
>>> software into cached memory directly.
>>>
>>> Supported ring modes:
>>> - Ring Mode
>>> - Messaging Mode
>>> - Credentials Mode
>>> - Queue Manager Mode
>>>
>>> TI-SCI integration:
>>>
>>> Texas Instrument's System Control Interface (TI-SCI) Message Protocol now
>>> has control over Ringacc module resources management (RM) and Rings
>>> configuration.
>>>
>>> The corresponding support of TI-SCI Ringacc module RM protocol
>>> introduced as option through DT parameters:
>>> - ti,sci: phandle on TI-SCI firmware controller DT node
>>> - ti,sci-dev-id: TI-SCI device identifier as per TI-SCI firmware spec
>>>
>>> if both parameters present - Ringacc driver will configure/free/reset
>>> Rings
>>> using TI-SCI Message Ringacc RM Protocol.
>>>
>>> The Ringacc driver manages Rings allocation by itself now and requests
>>> TI-SCI firmware to allocate and configure specific Rings only. It's done
>>> this way because, Linux driver implements two stage Rings allocation and
>>> configuration (allocate ring and configure ring) while I-SCI Message
>>
>> I-SCI should be TI-SCI I believe.
> 
> Yes, it supposed to be.
> 
>>
>>> Protocol supports only one combined operation (allocate+configure).
>>>
>>> Grygorii Strashko <grygorii.strashko@ti.com>
>>
>> Above seems to be missing SoB?
> 
> Oh, it is really missing.
> 
>>
>>> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
>>> ---
>>>    drivers/soc/ti/Kconfig            |   17 +
>>>    drivers/soc/ti/Makefile           |    1 +
>>>    drivers/soc/ti/k3-ringacc.c       | 1191 +++++++++++++++++++++++++++++
>>>    include/linux/soc/ti/k3-ringacc.h |  262 +++++++
>>>    4 files changed, 1471 insertions(+)
>>>    create mode 100644 drivers/soc/ti/k3-ringacc.c
>>>    create mode 100644 include/linux/soc/ti/k3-ringacc.h
>>>
>>> diff --git a/drivers/soc/ti/Kconfig b/drivers/soc/ti/Kconfig
>>> index cf545f428d03..10c76faa503e 100644
>>> --- a/drivers/soc/ti/Kconfig
>>> +++ b/drivers/soc/ti/Kconfig
>>> @@ -80,6 +80,23 @@ config TI_SCI_PM_DOMAINS
>>>          called ti_sci_pm_domains. Note this is needed early in boot
>>> before
>>>          rootfs may be available.
>>>    +config TI_K3_RINGACC
>>> +    tristate "K3 Ring accelerator Sub System"
>>> +    depends on ARCH_K3 || COMPILE_TEST
>>> +    depends on TI_SCI_INTA_IRQCHIP
>>> +    default y
>>> +    help
>>> +      Say y here to support the K3 Ring accelerator module.
>>> +      The Ring Accelerator (RINGACC or RA)  provides hardware
>>> acceleration
>>> +      to enable straightforward passing of work between a producer
>>> +      and a consumer. There is one RINGACC module per NAVSS on TI
>>> AM65x SoCs
>>> +      If unsure, say N.
>>> +
>>> +config TI_K3_RINGACC_DEBUG
>>> +    tristate "K3 Ring accelerator Sub System tests and debug"
>>> +    depends on TI_K3_RINGACC
>>> +    default n
>>> +
>>>    endif # SOC_TI
>>>      config TI_SCI_INTA_MSI_DOMAIN
>>> diff --git a/drivers/soc/ti/Makefile b/drivers/soc/ti/Makefile
>>> index b3868d392d4f..cc4bc8b08bf5 100644
>>> --- a/drivers/soc/ti/Makefile
>>> +++ b/drivers/soc/ti/Makefile
>>> @@ -9,3 +9,4 @@ obj-$(CONFIG_AMX3_PM)            += pm33xx.o
>>>    obj-$(CONFIG_WKUP_M3_IPC)        += wkup_m3_ipc.o
>>>    obj-$(CONFIG_TI_SCI_PM_DOMAINS)        += ti_sci_pm_domains.o
>>>    obj-$(CONFIG_TI_SCI_INTA_MSI_DOMAIN)    += ti_sci_inta_msi.o
>>> +obj-$(CONFIG_TI_K3_RINGACC)        += k3-ringacc.o
>>> diff --git a/drivers/soc/ti/k3-ringacc.c b/drivers/soc/ti/k3-ringacc.c
>>> new file mode 100644
>>> index 000000000000..401dfc963319
>>> --- /dev/null
>>> +++ b/drivers/soc/ti/k3-ringacc.c
>>> @@ -0,0 +1,1191 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +/*
>>> + * TI K3 NAVSS Ring Accelerator subsystem driver
>>> + *
>>> + * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
>>> + */
>>> +
>>> +#include <linux/dma-mapping.h>
>>> +#include <linux/io.h>
>>> +#include <linux/module.h>
>>> +#include <linux/of.h>
>>> +#include <linux/platform_device.h>
>>> +#include <linux/pm_runtime.h>
>>> +#include <linux/soc/ti/k3-ringacc.h>
>>> +#include <linux/soc/ti/ti_sci_protocol.h>
>>> +#include <linux/soc/ti/ti_sci_inta_msi.h>
>>> +#include <linux/of_irq.h>
>>> +#include <linux/irqdomain.h>
>>> +
>>> +static LIST_HEAD(k3_ringacc_list);
>>> +static DEFINE_MUTEX(k3_ringacc_list_lock);
>>> +
>>> +#ifdef CONFIG_TI_K3_RINGACC_DEBUG
>>> +#define    k3_nav_dbg(dev, arg...) dev_err(dev, arg)
>>
>> dev_err seems exaggeration for debug purposes, maybe just dev_info.
>>
>>> +static    void dbg_writel(u32 v, void __iomem *reg)
>>> +{
>>> +    pr_err("WRITEL(32): v(%08X)-->reg(%p)\n", v, reg);
>>
>> Again, maybe just pr_info.
> 
> I think I'll just drop CONFIG_TI_K3_RINGACC_DEBUG altogether along with
> dbg_writel/dbg_readl/k3_nav_dbg and use dev_dbg() when appropriate.

Sounds good.

> 
>>
>>> +    writel(v, reg);
>>> +}
>>> +
>>> +static    u32 dbg_readl(void __iomem *reg)
>>> +{
>>> +    u32 v;
>>> +
>>> +    v = readl(reg);
>>> +    pr_err("READL(32): v(%08X)<--reg(%p)\n", v, reg);
>>> +    return v;
>>> +}
>>> +#else
>>> +#define    k3_nav_dbg(dev, arg...) dev_dbg(dev, arg)
>>> +#define dbg_writel(v, reg) writel(v, reg)
>>
>> Do you need to use hard writel, writel_relaxed is not enough?
> 
> not sure if we really need the barriers, but __raw_writel() should be
> fine here imho

xxx_relaxed relaxed versions should be used only when necessary and with
adding appropriate comments why they've been used and what benefits from using
them for each particular case.
So, i do not agree with this blind conversation.

> 
>>> +
>>> +#define dbg_readl(reg) readl(reg)
>>
>> Same as above but for read?
> 
> __raw_readl() could be fine in also.

No. __raw_xxx api should never be used by drivers.


> 
> ...
> 
>>> +/**
>>> + * struct k3_ringacc - Rings accelerator descriptor
>>> + *
>>> + * @dev - pointer on RA device
>>> + * @proxy_gcfg - RA proxy global config registers
>>> + * @proxy_target_base - RA proxy datapath region
>>> + * @num_rings - number of ring in RA
>>> + * @rm_gp_range - general purpose rings range from tisci
>>> + * @dma_ring_reset_quirk - DMA reset w/a enable
>>> + * @num_proxies - number of RA proxies
>>> + * @rings - array of rings descriptors (struct @k3_ring)
>>> + * @list - list of RAs in the system
>>> + * @tisci - pointer ti-sci handle
>>> + * @tisci_ring_ops - ti-sci rings ops
>>> + * @tisci_dev_id - ti-sci device id
>>> + */

...

>>> +
>>> +#ifdef CONFIG_TI_K3_RINGACC_DEBUG
>>> +void k3_ringacc_ring_dump(struct k3_ring *ring)
>>> +{
>>> +    struct device *dev = ring->parent->dev;
>>> +
>>> +    k3_nav_dbg(dev, "dump ring: %d\n", ring->ring_id);
>>> +    k3_nav_dbg(dev, "dump mem virt %p, dma %pad\n",
>>> +           ring->ring_mem_virt, &ring->ring_mem_dma);
>>> +    k3_nav_dbg(dev, "dump elmsize %d, size %d, mode %d, proxy_id %d\n",
>>> +           ring->elm_size, ring->size, ring->mode, ring->proxy_id);
>>> +
>>> +    k3_nav_dbg(dev, "dump ring_rt_regs: db%08x\n",
>>> +           readl(&ring->rt->db));
>>
>> Why not use readl_relaxed in this func?
> 
> __raw_readl() might be enough?

No Raw, but this seems only one place where relaxed version can be used.

> 
>>
>>> +    k3_nav_dbg(dev, "dump occ%08x\n",
>>> +           readl(&ring->rt->occ));
>>> +    k3_nav_dbg(dev, "dump indx%08x\n",
>>> +           readl(&ring->rt->indx));
>>> +    k3_nav_dbg(dev, "dump hwocc%08x\n",
>>> +           readl(&ring->rt->hwocc));
>>> +    k3_nav_dbg(dev, "dump hwindx%08x\n",
>>> +           readl(&ring->rt->hwindx));
>>> +
>>> +    if (ring->ring_mem_virt)
>>> +        print_hex_dump(KERN_ERR, "dump ring_mem_virt ",
>>> +                   DUMP_PREFIX_NONE, 16, 1,
>>> +                   ring->ring_mem_virt, 16 * 8, false);
>>> +}
>>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_dump);
>>
>> Do you really need to export a debug function?
> 
> It might come helpful for clients to dump the ring status runtime, but
> since we don't have users, I'll move it to static.

Yep. It was exported for debug purposes. But hence there are no active users - cna be removed.

> 
>>> +#endif
>>> +
>>> +struct k3_ring *k3_ringacc_request_ring(struct k3_ringacc *ringacc,
>>> +                    int id, u32 flags)
>>> +{
>>> +    int proxy_id = K3_RINGACC_PROXY_NOT_USED;
>>> +
>>> +    mutex_lock(&ringacc->req_lock);
>>> +
>>> +    if (id == K3_RINGACC_RING_ID_ANY) {
>>> +        /* Request for any general purpose ring */
>>> +        struct ti_sci_resource_desc *gp_rings =
>>> +                        &ringacc->rm_gp_range->desc[0];
>>> +        unsigned long size;
>>> +
>>> +        size = gp_rings->start + gp_rings->num;
>>> +        id = find_next_zero_bit(ringacc->rings_inuse, size,
>>> +                    gp_rings->start);
>>> +        if (id == size)
>>> +            goto error;
>>> +    } else if (id < 0) {
>>> +        goto error;
>>> +    }
>>> +
>>> +    if (test_bit(id, ringacc->rings_inuse) &&
>>> +        !(ringacc->rings[id].flags & K3_RING_FLAG_SHARED))
>>> +        goto error;
>>> +    else if (ringacc->rings[id].flags & K3_RING_FLAG_SHARED)
>>> +        goto out;
>>> +
>>> +    if (flags & K3_RINGACC_RING_USE_PROXY) {
>>> +        proxy_id = find_next_zero_bit(ringacc->proxy_inuse,
>>> +                          ringacc->num_proxies, 0);
>>> +        if (proxy_id == ringacc->num_proxies)
>>> +            goto error;
>>> +    }
>>> +
>>> +    if (!try_module_get(ringacc->dev->driver->owner))
>>> +        goto error;
>>> +
>>> +    if (proxy_id != K3_RINGACC_PROXY_NOT_USED) {
>>> +        set_bit(proxy_id, ringacc->proxy_inuse);
>>> +        ringacc->rings[id].proxy_id = proxy_id;
>>> +        k3_nav_dbg(ringacc->dev, "Giving ring#%d proxy#%d\n",
>>> +               id, proxy_id);
>>> +    } else {
>>> +        k3_nav_dbg(ringacc->dev, "Giving ring#%d\n", id);
>>> +    }
>>> +
>>> +    set_bit(id, ringacc->rings_inuse);
>>> +out:
>>> +    ringacc->rings[id].use_count++;
>>> +    mutex_unlock(&ringacc->req_lock);
>>> +    return &ringacc->rings[id];
>>> +
>>> +error:
>>> +    mutex_unlock(&ringacc->req_lock);
>>> +    return NULL;
>>> +}
>>> +EXPORT_SYMBOL_GPL(k3_ringacc_request_ring);
>>> +
>>> +static void k3_ringacc_ring_reset_sci(struct k3_ring *ring)
>>> +{
>>> +    struct k3_ringacc *ringacc = ring->parent;
>>> +    int ret;
>>> +
>>> +    ret = ringacc->tisci_ring_ops->config(
>>> +            ringacc->tisci,
>>> +            TI_SCI_MSG_VALUE_RM_RING_COUNT_VALID,
>>> +            ringacc->tisci_dev_id,
>>> +            ring->ring_id,
>>> +            0,
>>> +            0,
>>> +            ring->size,
>>> +            0,
>>> +            0,
>>> +            0);
>>> +    if (ret)
>>> +        dev_err(ringacc->dev, "TISCI reset ring fail (%d) ring_idx
>>> %d\n",
>>> +            ret, ring->ring_id);
>>
>> Return value of sci ops is masked, why not return it and let the caller
>> handle it properly?
>>
>> Same comment for anything similar that follows.
> 
> Hrm, there is not much a caller can do other than PANIC in case the ring
> configuration fails.
> I can probagate the error, but not sure what action can be taken, if any.
> 
>>> +}
>>> +
>>> +void k3_ringacc_ring_reset(struct k3_ring *ring)
>>> +{
>>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>>> +        return;
>>> +
>>> +    ring->occ = 0;
>>> +    ring->free = 0;
>>> +    ring->rindex = 0;
>>> +    ring->windex = 0;
>>> +
>>> +    k3_ringacc_ring_reset_sci(ring);
>>> +}
>>> +EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset);
>>> +
>>> +static void k3_ringacc_ring_reconfig_qmode_sci(struct k3_ring *ring,
>>> +                           enum k3_ring_mode mode)
>>> +{
>>> +    struct k3_ringacc *ringacc = ring->parent;
>>> +    int ret;
>>> +
>>> +    ret = ringacc->tisci_ring_ops->config(
>>> +            ringacc->tisci,
>>> +            TI_SCI_MSG_VALUE_RM_RING_MODE_VALID,
>>> +            ringacc->tisci_dev_id,
>>> +            ring->ring_id,
>>> +            0,
>>> +            0,
>>> +            0,
>>> +            mode,
>>> +            0,
>>> +            0);
>>> +    if (ret)
>>> +        dev_err(ringacc->dev, "TISCI reconf qmode fail (%d) ring_idx
>>> %d\n",
>>> +            ret, ring->ring_id);
>>> +}
>>> +
>>> +void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ)
>>> +{
>>> +    if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
>>> +        return;
>>> +
>>> +    if (!ring->parent->dma_ring_reset_quirk)
>>> +        return;
>>> +
>>> +    if (!occ)
>>> +        occ = dbg_readl(&ring->rt->occ);
>>> +
>>> +    if (occ) {
>>> +        u32 db_ring_cnt, db_ring_cnt_cur;
>>> +
>>> +        k3_nav_dbg(ring->parent->dev, "%s %u occ: %u\n", __func__,
>>> +               ring->ring_id, occ);
>>> +        /* 2. Reset the ring */
>>
>> 2? Where is 1?
> 
> Oh, I'll fix the numbering.

1. is 'Get ring occupancy count"
I think you can just drop numbering

> 
>>
>>> +        k3_ringacc_ring_reset_sci(ring);
>>> +
>>> +        /*
>>> +         * 3. Setup the ring in ring/doorbell mode
>>> +         * (if not already in this mode)
>>> +         */
>>> +        if (ring->mode != K3_RINGACC_RING_MODE_RING)
>>> +            k3_ringacc_ring_reconfig_qmode_sci(
>>> +                    ring, K3_RINGACC_RING_MODE_RING);
>>> +        /*
>>> +         * 4. Ring the doorbell 2**22 – ringOcc times.
>>> +         * This will wrap the internal UDMAP ring state occupancy
>>> +         * counter (which is 21-bits wide) to 0.
>>> +         */
>>> +        db_ring_cnt = (1U << 22) - occ;
>>> +
>>> +        while (db_ring_cnt != 0) {
>>> +            /*
>>> +             * Ring the doorbell with the maximum count each
>>> +             * iteration if possible to minimize the total
>>> +             * of writes
>>> +             */
>>> +            if (db_ring_cnt > K3_RINGACC_MAX_DB_RING_CNT)
>>> +                db_ring_cnt_cur = K3_RINGACC_MAX_DB_RING_CNT;
>>> +            else
>>> +                db_ring_cnt_cur = db_ring_cnt;
>>> +
>>> +            writel(db_ring_cnt_cur, &ring->rt->db);
>>> +            db_ring_cnt -= db_ring_cnt_cur;
>>> +        }
>>> +
>>> +        /* 5. Restore the original ring mode (if not ring mode) */
>>> +        if (ring->mode != K3_RINGACC_RING_MODE_RING)
>>> +            k3_ringacc_ring_reconfig_qmode_sci(ring, ring->mode);
>>> +    }
>>> +
>>> +    /* 2. Reset the ring */
>>

>>> +
>>> +u32 k3_ringacc_get_tisci_dev_id(struct k3_ring *ring)
>>> +{
>>> +    if (!ring)
>>> +        return -EINVAL;
>>> +
>>
>> What if parent is NULL? Can it ever be here?
> 
> No, parent can not be NULL as the client would not have the ring in the
> first place.
> 
>>
>>> +    return ring->parent->tisci_dev_id;
>>> +}
>>> +EXPORT_SYMBOL_GPL(k3_ringacc_get_tisci_dev_id);
>>> +
>>> +int k3_ringacc_get_ring_irq_num(struct k3_ring *ring)
>>> +{
>>> +    int irq_num;
>>> +
>>> +    if (!ring)
>>> +        return -EINVAL;
>>> +
>>> +    irq_num = ti_sci_inta_msi_get_virq(ring->parent->dev,
>>> ring->ring_id);
>>> +    if (irq_num <= 0)
>>> +        irq_num = -EINVAL;
>>> +    return irq_num;
>>> +}
>>> +EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_irq_num);
>>> +
>>> +static int k3_ringacc_ring_cfg_sci(struct k3_ring *ring)
>>> +{
>>> +    struct k3_ringacc *ringacc = ring->parent;
>>> +    u32 ring_idx;
>>> +    int ret;
>>> +
>>> +    if (!ringacc->tisci)
>>> +        return -EINVAL;
>>> +
>>> +    ring_idx = ring->ring_id;
>>> +    ret = ringacc->tisci_ring_ops->config(
>>> +            ringacc->tisci,
>>> +            TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
>>> +            ringacc->tisci_dev_id,
>>> +            ring_idx,
>>> +            lower_32_bits(ring->ring_mem_dma),
>>> +            upper_32_bits(ring->ring_mem_dma),
>>> +            ring->size,
>>> +            ring->mode,
>>> +            ring->elm_size,
>>> +            0);
>>> +    if (ret)
>>> +        dev_err(ringacc->dev, "TISCI config ring fail (%d) ring_idx
>>> %d\n",
>>> +            ret, ring_idx);
>>> +
>>> +    return ret;
>>> +}
>>> +
>>> +int k3_ringacc_ring_cfg(struct k3_ring *ring, struct k3_ring_cfg *cfg)
>>> +{
>>> +    struct k3_ringacc *ringacc = ring->parent;
>>> +    int ret = 0;
>>> +
>>> +    if (!ring || !cfg)
>>> +        return -EINVAL;
>>> +    if (cfg->elm_size > K3_RINGACC_RING_ELSIZE_256 ||
>>> +        cfg->mode > K3_RINGACC_RING_MODE_QM ||
>>> +        cfg->size & ~K3_RINGACC_CFG_RING_SIZE_ELCNT_MASK ||
>>> +        !test_bit(ring->ring_id, ringacc->rings_inuse))
>>> +        return -EINVAL;
>>> +
>>> +    if (ring->use_count != 1)
>>
>> Hmm, isn't this a failure actually?
> 
> Yes, it is: -EBUSY

No. This is for shared rings.
0 - should never happens once ring is requested.
1 - only one user - configure ring
>1 - shared ring which is configured already - just exit as ring configure already.

> 
>>> +        return 0;
>>> +
>>> +    ring->size = cfg->size;
>>> +    ring->elm_size = cfg->elm_size;
>>> +    ring->mode = cfg->mode;
>>> +    ring->occ = 0;
>>> +    ring->free = 0;
>>> +    ring->rindex = 0;
>>> +    ring->windex = 0;
>>> +

[...]
diff mbox series

Patch

diff --git a/drivers/soc/ti/Kconfig b/drivers/soc/ti/Kconfig
index cf545f428d03..10c76faa503e 100644
--- a/drivers/soc/ti/Kconfig
+++ b/drivers/soc/ti/Kconfig
@@ -80,6 +80,23 @@  config TI_SCI_PM_DOMAINS
 	  called ti_sci_pm_domains. Note this is needed early in boot before
 	  rootfs may be available.
 
+config TI_K3_RINGACC
+	tristate "K3 Ring accelerator Sub System"
+	depends on ARCH_K3 || COMPILE_TEST
+	depends on TI_SCI_INTA_IRQCHIP
+	default y
+	help
+	  Say y here to support the K3 Ring accelerator module.
+	  The Ring Accelerator (RINGACC or RA)  provides hardware acceleration
+	  to enable straightforward passing of work between a producer
+	  and a consumer. There is one RINGACC module per NAVSS on TI AM65x SoCs
+	  If unsure, say N.
+
+config TI_K3_RINGACC_DEBUG
+	tristate "K3 Ring accelerator Sub System tests and debug"
+	depends on TI_K3_RINGACC
+	default n
+
 endif # SOC_TI
 
 config TI_SCI_INTA_MSI_DOMAIN
diff --git a/drivers/soc/ti/Makefile b/drivers/soc/ti/Makefile
index b3868d392d4f..cc4bc8b08bf5 100644
--- a/drivers/soc/ti/Makefile
+++ b/drivers/soc/ti/Makefile
@@ -9,3 +9,4 @@  obj-$(CONFIG_AMX3_PM)			+= pm33xx.o
 obj-$(CONFIG_WKUP_M3_IPC)		+= wkup_m3_ipc.o
 obj-$(CONFIG_TI_SCI_PM_DOMAINS)		+= ti_sci_pm_domains.o
 obj-$(CONFIG_TI_SCI_INTA_MSI_DOMAIN)	+= ti_sci_inta_msi.o
+obj-$(CONFIG_TI_K3_RINGACC)		+= k3-ringacc.o
diff --git a/drivers/soc/ti/k3-ringacc.c b/drivers/soc/ti/k3-ringacc.c
new file mode 100644
index 000000000000..401dfc963319
--- /dev/null
+++ b/drivers/soc/ti/k3-ringacc.c
@@ -0,0 +1,1191 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI K3 NAVSS Ring Accelerator subsystem driver
+ *
+ * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/soc/ti/k3-ringacc.h>
+#include <linux/soc/ti/ti_sci_protocol.h>
+#include <linux/soc/ti/ti_sci_inta_msi.h>
+#include <linux/of_irq.h>
+#include <linux/irqdomain.h>
+
+static LIST_HEAD(k3_ringacc_list);
+static DEFINE_MUTEX(k3_ringacc_list_lock);
+
+#ifdef CONFIG_TI_K3_RINGACC_DEBUG
+#define	k3_nav_dbg(dev, arg...) dev_err(dev, arg)
+static	void dbg_writel(u32 v, void __iomem *reg)
+{
+	pr_err("WRITEL(32): v(%08X)-->reg(%p)\n", v, reg);
+	writel(v, reg);
+}
+
+static	u32 dbg_readl(void __iomem *reg)
+{
+	u32 v;
+
+	v = readl(reg);
+	pr_err("READL(32): v(%08X)<--reg(%p)\n", v, reg);
+	return v;
+}
+#else
+#define	k3_nav_dbg(dev, arg...) dev_dbg(dev, arg)
+#define dbg_writel(v, reg) writel(v, reg)
+
+#define dbg_readl(reg) readl(reg)
+#endif
+
+#define K3_RINGACC_CFG_RING_SIZE_ELCNT_MASK		GENMASK(19, 0)
+
+/**
+ * struct k3_ring_rt_regs -  The RA Control/Status Registers region
+ */
+struct k3_ring_rt_regs {
+	u32	resv_16[4];
+	u32	db;		/* RT Ring N Doorbell Register */
+	u32	resv_4[1];
+	u32	occ;		/* RT Ring N Occupancy Register */
+	u32	indx;		/* RT Ring N Current Index Register */
+	u32	hwocc;		/* RT Ring N Hardware Occupancy Register */
+	u32	hwindx;		/* RT Ring N Current Index Register */
+};
+
+#define K3_RINGACC_RT_REGS_STEP	0x1000
+
+/**
+ * struct k3_ring_fifo_regs -  The Ring Accelerator Queues Registers region
+ */
+struct k3_ring_fifo_regs {
+	u32	head_data[128];		/* Ring Head Entry Data Registers */
+	u32	tail_data[128];		/* Ring Tail Entry Data Registers */
+	u32	peek_head_data[128];	/* Ring Peek Head Entry Data Regs */
+	u32	peek_tail_data[128];	/* Ring Peek Tail Entry Data Regs */
+};
+
+/**
+ * struct k3_ringacc_proxy_gcfg_regs - RA Proxy Global Config MMIO Region
+ */
+struct k3_ringacc_proxy_gcfg_regs {
+	u32	revision;	/* Revision Register */
+	u32	config;		/* Config Register */
+};
+
+#define K3_RINGACC_PROXY_CFG_THREADS_MASK		GENMASK(15, 0)
+
+/**
+ * struct k3_ringacc_proxy_target_regs -  Proxy Datapath MMIO Region
+ */
+struct k3_ringacc_proxy_target_regs {
+	u32	control;	/* Proxy Control Register */
+	u32	status;		/* Proxy Status Register */
+	u8	resv_512[504];
+	u32	data[128];	/* Proxy Data Register */
+};
+
+#define K3_RINGACC_PROXY_TARGET_STEP	0x1000
+#define K3_RINGACC_PROXY_NOT_USED	(-1)
+
+enum k3_ringacc_proxy_access_mode {
+	PROXY_ACCESS_MODE_HEAD = 0,
+	PROXY_ACCESS_MODE_TAIL = 1,
+	PROXY_ACCESS_MODE_PEEK_HEAD = 2,
+	PROXY_ACCESS_MODE_PEEK_TAIL = 3,
+};
+
+#define K3_RINGACC_FIFO_WINDOW_SIZE_BYTES  (512U)
+#define K3_RINGACC_FIFO_REGS_STEP	0x1000
+#define K3_RINGACC_MAX_DB_RING_CNT    (127U)
+
+/**
+ * struct k3_ring_ops -  Ring operations
+ */
+struct k3_ring_ops {
+	int (*push_tail)(struct k3_ring *ring, void *elm);
+	int (*push_head)(struct k3_ring *ring, void *elm);
+	int (*pop_tail)(struct k3_ring *ring, void *elm);
+	int (*pop_head)(struct k3_ring *ring, void *elm);
+};
+
+/**
+ * struct k3_ring - RA Ring descriptor
+ *
+ * @rt - Ring control/status registers
+ * @fifos - Ring queues registers
+ * @proxy - Ring Proxy Datapath registers
+ * @ring_mem_dma - Ring buffer dma address
+ * @ring_mem_virt - Ring buffer virt address
+ * @ops - Ring operations
+ * @size - Ring size in elements
+ * @elm_size - Size of the ring element
+ * @mode - Ring mode
+ * @flags - flags
+ * @free - Number of free elements
+ * @occ - Ring occupancy
+ * @windex - Write index (only for @K3_RINGACC_RING_MODE_RING)
+ * @rindex - Read index (only for @K3_RINGACC_RING_MODE_RING)
+ * @ring_id - Ring Id
+ * @parent - Pointer on struct @k3_ringacc
+ * @use_count - Use count for shared rings
+ * @proxy_id - RA Ring Proxy Id (only if @K3_RINGACC_RING_USE_PROXY)
+ */
+struct k3_ring {
+	struct k3_ring_rt_regs __iomem *rt;
+	struct k3_ring_fifo_regs __iomem *fifos;
+	struct k3_ringacc_proxy_target_regs  __iomem *proxy;
+	dma_addr_t	ring_mem_dma;
+	void		*ring_mem_virt;
+	struct k3_ring_ops *ops;
+	u32		size;
+	enum k3_ring_size elm_size;
+	enum k3_ring_mode mode;
+	u32		flags;
+#define K3_RING_FLAG_BUSY	BIT(1)
+#define K3_RING_FLAG_SHARED	BIT(2)
+	u32		free;
+	u32		occ;
+	u32		windex;
+	u32		rindex;
+	u32		ring_id;
+	struct k3_ringacc	*parent;
+	u32		use_count;
+	int		proxy_id;
+};
+
+/**
+ * struct k3_ringacc - Rings accelerator descriptor
+ *
+ * @dev - pointer on RA device
+ * @proxy_gcfg - RA proxy global config registers
+ * @proxy_target_base - RA proxy datapath region
+ * @num_rings - number of ring in RA
+ * @rm_gp_range - general purpose rings range from tisci
+ * @dma_ring_reset_quirk - DMA reset w/a enable
+ * @num_proxies - number of RA proxies
+ * @rings - array of rings descriptors (struct @k3_ring)
+ * @list - list of RAs in the system
+ * @tisci - pointer ti-sci handle
+ * @tisci_ring_ops - ti-sci rings ops
+ * @tisci_dev_id - ti-sci device id
+ */
+struct k3_ringacc {
+	struct device *dev;
+	struct k3_ringacc_proxy_gcfg_regs __iomem *proxy_gcfg;
+	void __iomem *proxy_target_base;
+	u32 num_rings; /* number of rings in Ringacc module */
+	unsigned long *rings_inuse;
+	struct ti_sci_resource *rm_gp_range;
+
+	bool dma_ring_reset_quirk;
+	u32 num_proxies;
+	unsigned long *proxy_inuse;
+
+	struct k3_ring *rings;
+	struct list_head list;
+	struct mutex req_lock; /* protect rings allocation */
+
+	const struct ti_sci_handle *tisci;
+	const struct ti_sci_rm_ringacc_ops *tisci_ring_ops;
+	u32  tisci_dev_id;
+};
+
+static long k3_ringacc_ring_get_fifo_pos(struct k3_ring *ring)
+{
+	return K3_RINGACC_FIFO_WINDOW_SIZE_BYTES -
+	       (4 << ring->elm_size);
+}
+
+static void *k3_ringacc_get_elm_addr(struct k3_ring *ring, u32 idx)
+{
+	return (idx * (4 << ring->elm_size) + ring->ring_mem_virt);
+}
+
+static int k3_ringacc_ring_push_mem(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_pop_mem(struct k3_ring *ring, void *elem);
+
+static struct k3_ring_ops k3_ring_mode_ring_ops = {
+		.push_tail = k3_ringacc_ring_push_mem,
+		.pop_head = k3_ringacc_ring_pop_mem,
+};
+
+static int k3_ringacc_ring_push_io(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_pop_io(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_push_head_io(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_pop_tail_io(struct k3_ring *ring, void *elem);
+
+static struct k3_ring_ops k3_ring_mode_msg_ops = {
+		.push_tail = k3_ringacc_ring_push_io,
+		.push_head = k3_ringacc_ring_push_head_io,
+		.pop_tail = k3_ringacc_ring_pop_tail_io,
+		.pop_head = k3_ringacc_ring_pop_io,
+};
+
+static int k3_ringacc_ring_push_head_proxy(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_push_tail_proxy(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_pop_head_proxy(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_pop_tail_proxy(struct k3_ring *ring, void *elem);
+
+static struct k3_ring_ops k3_ring_mode_proxy_ops = {
+		.push_tail = k3_ringacc_ring_push_tail_proxy,
+		.push_head = k3_ringacc_ring_push_head_proxy,
+		.pop_tail = k3_ringacc_ring_pop_tail_proxy,
+		.pop_head = k3_ringacc_ring_pop_head_proxy,
+};
+
+#ifdef CONFIG_TI_K3_RINGACC_DEBUG
+void k3_ringacc_ring_dump(struct k3_ring *ring)
+{
+	struct device *dev = ring->parent->dev;
+
+	k3_nav_dbg(dev, "dump ring: %d\n", ring->ring_id);
+	k3_nav_dbg(dev, "dump mem virt %p, dma %pad\n",
+		   ring->ring_mem_virt, &ring->ring_mem_dma);
+	k3_nav_dbg(dev, "dump elmsize %d, size %d, mode %d, proxy_id %d\n",
+		   ring->elm_size, ring->size, ring->mode, ring->proxy_id);
+
+	k3_nav_dbg(dev, "dump ring_rt_regs: db%08x\n",
+		   readl(&ring->rt->db));
+	k3_nav_dbg(dev, "dump occ%08x\n",
+		   readl(&ring->rt->occ));
+	k3_nav_dbg(dev, "dump indx%08x\n",
+		   readl(&ring->rt->indx));
+	k3_nav_dbg(dev, "dump hwocc%08x\n",
+		   readl(&ring->rt->hwocc));
+	k3_nav_dbg(dev, "dump hwindx%08x\n",
+		   readl(&ring->rt->hwindx));
+
+	if (ring->ring_mem_virt)
+		print_hex_dump(KERN_ERR, "dump ring_mem_virt ",
+			       DUMP_PREFIX_NONE, 16, 1,
+			       ring->ring_mem_virt, 16 * 8, false);
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_dump);
+#endif
+
+struct k3_ring *k3_ringacc_request_ring(struct k3_ringacc *ringacc,
+					int id, u32 flags)
+{
+	int proxy_id = K3_RINGACC_PROXY_NOT_USED;
+
+	mutex_lock(&ringacc->req_lock);
+
+	if (id == K3_RINGACC_RING_ID_ANY) {
+		/* Request for any general purpose ring */
+		struct ti_sci_resource_desc *gp_rings =
+						&ringacc->rm_gp_range->desc[0];
+		unsigned long size;
+
+		size = gp_rings->start + gp_rings->num;
+		id = find_next_zero_bit(ringacc->rings_inuse, size,
+					gp_rings->start);
+		if (id == size)
+			goto error;
+	} else if (id < 0) {
+		goto error;
+	}
+
+	if (test_bit(id, ringacc->rings_inuse) &&
+	    !(ringacc->rings[id].flags & K3_RING_FLAG_SHARED))
+		goto error;
+	else if (ringacc->rings[id].flags & K3_RING_FLAG_SHARED)
+		goto out;
+
+	if (flags & K3_RINGACC_RING_USE_PROXY) {
+		proxy_id = find_next_zero_bit(ringacc->proxy_inuse,
+					      ringacc->num_proxies, 0);
+		if (proxy_id == ringacc->num_proxies)
+			goto error;
+	}
+
+	if (!try_module_get(ringacc->dev->driver->owner))
+		goto error;
+
+	if (proxy_id != K3_RINGACC_PROXY_NOT_USED) {
+		set_bit(proxy_id, ringacc->proxy_inuse);
+		ringacc->rings[id].proxy_id = proxy_id;
+		k3_nav_dbg(ringacc->dev, "Giving ring#%d proxy#%d\n",
+			   id, proxy_id);
+	} else {
+		k3_nav_dbg(ringacc->dev, "Giving ring#%d\n", id);
+	}
+
+	set_bit(id, ringacc->rings_inuse);
+out:
+	ringacc->rings[id].use_count++;
+	mutex_unlock(&ringacc->req_lock);
+	return &ringacc->rings[id];
+
+error:
+	mutex_unlock(&ringacc->req_lock);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_request_ring);
+
+static void k3_ringacc_ring_reset_sci(struct k3_ring *ring)
+{
+	struct k3_ringacc *ringacc = ring->parent;
+	int ret;
+
+	ret = ringacc->tisci_ring_ops->config(
+			ringacc->tisci,
+			TI_SCI_MSG_VALUE_RM_RING_COUNT_VALID,
+			ringacc->tisci_dev_id,
+			ring->ring_id,
+			0,
+			0,
+			ring->size,
+			0,
+			0,
+			0);
+	if (ret)
+		dev_err(ringacc->dev, "TISCI reset ring fail (%d) ring_idx %d\n",
+			ret, ring->ring_id);
+}
+
+void k3_ringacc_ring_reset(struct k3_ring *ring)
+{
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return;
+
+	ring->occ = 0;
+	ring->free = 0;
+	ring->rindex = 0;
+	ring->windex = 0;
+
+	k3_ringacc_ring_reset_sci(ring);
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset);
+
+static void k3_ringacc_ring_reconfig_qmode_sci(struct k3_ring *ring,
+					       enum k3_ring_mode mode)
+{
+	struct k3_ringacc *ringacc = ring->parent;
+	int ret;
+
+	ret = ringacc->tisci_ring_ops->config(
+			ringacc->tisci,
+			TI_SCI_MSG_VALUE_RM_RING_MODE_VALID,
+			ringacc->tisci_dev_id,
+			ring->ring_id,
+			0,
+			0,
+			0,
+			mode,
+			0,
+			0);
+	if (ret)
+		dev_err(ringacc->dev, "TISCI reconf qmode fail (%d) ring_idx %d\n",
+			ret, ring->ring_id);
+}
+
+void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ)
+{
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return;
+
+	if (!ring->parent->dma_ring_reset_quirk)
+		return;
+
+	if (!occ)
+		occ = dbg_readl(&ring->rt->occ);
+
+	if (occ) {
+		u32 db_ring_cnt, db_ring_cnt_cur;
+
+		k3_nav_dbg(ring->parent->dev, "%s %u occ: %u\n", __func__,
+			   ring->ring_id, occ);
+		/* 2. Reset the ring */
+		k3_ringacc_ring_reset_sci(ring);
+
+		/*
+		 * 3. Setup the ring in ring/doorbell mode
+		 * (if not already in this mode)
+		 */
+		if (ring->mode != K3_RINGACC_RING_MODE_RING)
+			k3_ringacc_ring_reconfig_qmode_sci(
+					ring, K3_RINGACC_RING_MODE_RING);
+		/*
+		 * 4. Ring the doorbell 2**22 – ringOcc times.
+		 * This will wrap the internal UDMAP ring state occupancy
+		 * counter (which is 21-bits wide) to 0.
+		 */
+		db_ring_cnt = (1U << 22) - occ;
+
+		while (db_ring_cnt != 0) {
+			/*
+			 * Ring the doorbell with the maximum count each
+			 * iteration if possible to minimize the total
+			 * of writes
+			 */
+			if (db_ring_cnt > K3_RINGACC_MAX_DB_RING_CNT)
+				db_ring_cnt_cur = K3_RINGACC_MAX_DB_RING_CNT;
+			else
+				db_ring_cnt_cur = db_ring_cnt;
+
+			writel(db_ring_cnt_cur, &ring->rt->db);
+			db_ring_cnt -= db_ring_cnt_cur;
+		}
+
+		/* 5. Restore the original ring mode (if not ring mode) */
+		if (ring->mode != K3_RINGACC_RING_MODE_RING)
+			k3_ringacc_ring_reconfig_qmode_sci(ring, ring->mode);
+	}
+
+	/* 2. Reset the ring */
+	k3_ringacc_ring_reset(ring);
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset_dma);
+
+static void k3_ringacc_ring_free_sci(struct k3_ring *ring)
+{
+	struct k3_ringacc *ringacc = ring->parent;
+	int ret;
+
+	ret = ringacc->tisci_ring_ops->config(
+			ringacc->tisci,
+			TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
+			ringacc->tisci_dev_id,
+			ring->ring_id,
+			0,
+			0,
+			0,
+			0,
+			0,
+			0);
+	if (ret)
+		dev_err(ringacc->dev, "TISCI ring free fail (%d) ring_idx %d\n",
+			ret, ring->ring_id);
+}
+
+int k3_ringacc_ring_free(struct k3_ring *ring)
+{
+	struct k3_ringacc *ringacc;
+
+	if (!ring)
+		return -EINVAL;
+
+	ringacc = ring->parent;
+
+	k3_nav_dbg(ring->parent->dev, "flags: 0x%08x\n", ring->flags);
+
+	if (!test_bit(ring->ring_id, ringacc->rings_inuse))
+		return -EINVAL;
+
+	mutex_lock(&ringacc->req_lock);
+
+	if (--ring->use_count)
+		goto out;
+
+	if (!(ring->flags & K3_RING_FLAG_BUSY))
+		goto no_init;
+
+	k3_ringacc_ring_free_sci(ring);
+
+	dma_free_coherent(ringacc->dev,
+			  ring->size * (4 << ring->elm_size),
+			  ring->ring_mem_virt, ring->ring_mem_dma);
+	ring->flags = 0;
+	ring->ops = NULL;
+	if (ring->proxy_id != K3_RINGACC_PROXY_NOT_USED) {
+		clear_bit(ring->proxy_id, ringacc->proxy_inuse);
+		ring->proxy = NULL;
+		ring->proxy_id = K3_RINGACC_PROXY_NOT_USED;
+	}
+
+no_init:
+	clear_bit(ring->ring_id, ringacc->rings_inuse);
+
+	module_put(ringacc->dev->driver->owner);
+
+out:
+	mutex_unlock(&ringacc->req_lock);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_free);
+
+u32 k3_ringacc_get_ring_id(struct k3_ring *ring)
+{
+	if (!ring)
+		return -EINVAL;
+
+	return ring->ring_id;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_id);
+
+u32 k3_ringacc_get_tisci_dev_id(struct k3_ring *ring)
+{
+	if (!ring)
+		return -EINVAL;
+
+	return ring->parent->tisci_dev_id;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_get_tisci_dev_id);
+
+int k3_ringacc_get_ring_irq_num(struct k3_ring *ring)
+{
+	int irq_num;
+
+	if (!ring)
+		return -EINVAL;
+
+	irq_num = ti_sci_inta_msi_get_virq(ring->parent->dev, ring->ring_id);
+	if (irq_num <= 0)
+		irq_num = -EINVAL;
+	return irq_num;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_irq_num);
+
+static int k3_ringacc_ring_cfg_sci(struct k3_ring *ring)
+{
+	struct k3_ringacc *ringacc = ring->parent;
+	u32 ring_idx;
+	int ret;
+
+	if (!ringacc->tisci)
+		return -EINVAL;
+
+	ring_idx = ring->ring_id;
+	ret = ringacc->tisci_ring_ops->config(
+			ringacc->tisci,
+			TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
+			ringacc->tisci_dev_id,
+			ring_idx,
+			lower_32_bits(ring->ring_mem_dma),
+			upper_32_bits(ring->ring_mem_dma),
+			ring->size,
+			ring->mode,
+			ring->elm_size,
+			0);
+	if (ret)
+		dev_err(ringacc->dev, "TISCI config ring fail (%d) ring_idx %d\n",
+			ret, ring_idx);
+
+	return ret;
+}
+
+int k3_ringacc_ring_cfg(struct k3_ring *ring, struct k3_ring_cfg *cfg)
+{
+	struct k3_ringacc *ringacc = ring->parent;
+	int ret = 0;
+
+	if (!ring || !cfg)
+		return -EINVAL;
+	if (cfg->elm_size > K3_RINGACC_RING_ELSIZE_256 ||
+	    cfg->mode > K3_RINGACC_RING_MODE_QM ||
+	    cfg->size & ~K3_RINGACC_CFG_RING_SIZE_ELCNT_MASK ||
+	    !test_bit(ring->ring_id, ringacc->rings_inuse))
+		return -EINVAL;
+
+	if (ring->use_count != 1)
+		return 0;
+
+	ring->size = cfg->size;
+	ring->elm_size = cfg->elm_size;
+	ring->mode = cfg->mode;
+	ring->occ = 0;
+	ring->free = 0;
+	ring->rindex = 0;
+	ring->windex = 0;
+
+	if (ring->proxy_id != K3_RINGACC_PROXY_NOT_USED)
+		ring->proxy = ringacc->proxy_target_base +
+			      ring->proxy_id * K3_RINGACC_PROXY_TARGET_STEP;
+
+	switch (ring->mode) {
+	case K3_RINGACC_RING_MODE_RING:
+		ring->ops = &k3_ring_mode_ring_ops;
+		break;
+	case K3_RINGACC_RING_MODE_QM:
+		/*
+		 * In Queue mode elm_size can be 8 only and each operation
+		 * uses 2 element slots
+		 */
+		if (cfg->elm_size != K3_RINGACC_RING_ELSIZE_8 ||
+		    cfg->size % 2)
+			goto err_free_proxy;
+		/* else, fall through */
+	case K3_RINGACC_RING_MODE_MESSAGE:
+		if (ring->proxy)
+			ring->ops = &k3_ring_mode_proxy_ops;
+		else
+			ring->ops = &k3_ring_mode_msg_ops;
+		break;
+	default:
+		ring->ops = NULL;
+		ret = -EINVAL;
+		goto err_free_proxy;
+	};
+
+	ring->ring_mem_virt =
+			dma_alloc_coherent(ringacc->dev,
+					   ring->size * (4 << ring->elm_size),
+					   &ring->ring_mem_dma, GFP_KERNEL);
+	if (!ring->ring_mem_virt) {
+		dev_err(ringacc->dev, "Failed to alloc ring mem\n");
+		ret = -ENOMEM;
+		goto err_free_ops;
+	}
+
+	ret = k3_ringacc_ring_cfg_sci(ring);
+
+	if (ret)
+		goto err_free_mem;
+
+	ring->flags |= K3_RING_FLAG_BUSY;
+	ring->flags |= (cfg->flags & K3_RINGACC_RING_SHARED) ?
+			K3_RING_FLAG_SHARED : 0;
+
+	k3_ringacc_ring_dump(ring);
+
+	return 0;
+
+err_free_mem:
+	dma_free_coherent(ringacc->dev,
+			  ring->size * (4 << ring->elm_size),
+			  ring->ring_mem_virt,
+			  ring->ring_mem_dma);
+err_free_ops:
+	ring->ops = NULL;
+err_free_proxy:
+	ring->proxy = NULL;
+	return ret;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_cfg);
+
+u32 k3_ringacc_ring_get_size(struct k3_ring *ring)
+{
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	return ring->size;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_size);
+
+u32 k3_ringacc_ring_get_free(struct k3_ring *ring)
+{
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	if (!ring->free)
+		ring->free = ring->size - dbg_readl(&ring->rt->occ);
+
+	return ring->free;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_free);
+
+u32 k3_ringacc_ring_get_occ(struct k3_ring *ring)
+{
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	return dbg_readl(&ring->rt->occ);
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_occ);
+
+u32 k3_ringacc_ring_is_full(struct k3_ring *ring)
+{
+	return !k3_ringacc_ring_get_free(ring);
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_is_full);
+
+enum k3_ringacc_access_mode {
+	K3_RINGACC_ACCESS_MODE_PUSH_HEAD,
+	K3_RINGACC_ACCESS_MODE_POP_HEAD,
+	K3_RINGACC_ACCESS_MODE_PUSH_TAIL,
+	K3_RINGACC_ACCESS_MODE_POP_TAIL,
+	K3_RINGACC_ACCESS_MODE_PEEK_HEAD,
+	K3_RINGACC_ACCESS_MODE_PEEK_TAIL,
+};
+
+static int k3_ringacc_ring_cfg_proxy(struct k3_ring *ring,
+				     enum k3_ringacc_proxy_access_mode mode)
+{
+	u32 val;
+
+	val = ring->ring_id;
+	val |= mode << 16;
+	val |= ring->elm_size << 24;
+	dbg_writel(val, &ring->proxy->control);
+	return 0;
+}
+
+static int k3_ringacc_ring_access_proxy(struct k3_ring *ring, void *elem,
+					enum k3_ringacc_access_mode access_mode)
+{
+	void __iomem *ptr;
+
+	ptr = (void __iomem *)&ring->proxy->data;
+
+	switch (access_mode) {
+	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
+	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
+		k3_ringacc_ring_cfg_proxy(ring, PROXY_ACCESS_MODE_HEAD);
+		break;
+	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
+	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
+		k3_ringacc_ring_cfg_proxy(ring, PROXY_ACCESS_MODE_TAIL);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ptr += k3_ringacc_ring_get_fifo_pos(ring);
+
+	switch (access_mode) {
+	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
+	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
+		k3_nav_dbg(ring->parent->dev, "proxy:memcpy_fromio(x): --> ptr(%p), mode:%d\n",
+			   ptr, access_mode);
+		memcpy_fromio(elem, ptr, (4 << ring->elm_size));
+		ring->occ--;
+		break;
+	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
+	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
+		k3_nav_dbg(ring->parent->dev, "proxy:memcpy_toio(x): --> ptr(%p), mode:%d\n",
+			   ptr, access_mode);
+		memcpy_toio(ptr, elem, (4 << ring->elm_size));
+		ring->free--;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	k3_nav_dbg(ring->parent->dev, "proxy: free%d occ%d\n",
+		   ring->free, ring->occ);
+	return 0;
+}
+
+static int k3_ringacc_ring_push_head_proxy(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_proxy(ring, elem,
+					    K3_RINGACC_ACCESS_MODE_PUSH_HEAD);
+}
+
+static int k3_ringacc_ring_push_tail_proxy(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_proxy(ring, elem,
+					    K3_RINGACC_ACCESS_MODE_PUSH_TAIL);
+}
+
+static int k3_ringacc_ring_pop_head_proxy(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_proxy(ring, elem,
+					    K3_RINGACC_ACCESS_MODE_POP_HEAD);
+}
+
+static int k3_ringacc_ring_pop_tail_proxy(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_proxy(ring, elem,
+					    K3_RINGACC_ACCESS_MODE_POP_HEAD);
+}
+
+static int k3_ringacc_ring_access_io(struct k3_ring *ring, void *elem,
+				     enum k3_ringacc_access_mode access_mode)
+{
+	void __iomem *ptr;
+
+	switch (access_mode) {
+	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
+	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
+		ptr = (void __iomem *)&ring->fifos->head_data;
+		break;
+	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
+	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
+		ptr = (void __iomem *)&ring->fifos->tail_data;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ptr += k3_ringacc_ring_get_fifo_pos(ring);
+
+	switch (access_mode) {
+	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
+	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
+		k3_nav_dbg(ring->parent->dev, "memcpy_fromio(x): --> ptr(%p), mode:%d\n",
+			   ptr, access_mode);
+		memcpy_fromio(elem, ptr, (4 << ring->elm_size));
+		ring->occ--;
+		break;
+	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
+	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
+		k3_nav_dbg(ring->parent->dev, "memcpy_toio(x): --> ptr(%p), mode:%d\n",
+			   ptr, access_mode);
+		memcpy_toio(ptr, elem, (4 << ring->elm_size));
+		ring->free--;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	k3_nav_dbg(ring->parent->dev, "free%d index%d occ%d index%d\n",
+		   ring->free, ring->windex, ring->occ, ring->rindex);
+	return 0;
+}
+
+static int k3_ringacc_ring_push_head_io(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_io(ring, elem,
+					 K3_RINGACC_ACCESS_MODE_PUSH_HEAD);
+}
+
+static int k3_ringacc_ring_push_io(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_io(ring, elem,
+					 K3_RINGACC_ACCESS_MODE_PUSH_TAIL);
+}
+
+static int k3_ringacc_ring_pop_io(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_io(ring, elem,
+					 K3_RINGACC_ACCESS_MODE_POP_HEAD);
+}
+
+static int k3_ringacc_ring_pop_tail_io(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_io(ring, elem,
+					 K3_RINGACC_ACCESS_MODE_POP_HEAD);
+}
+
+static int k3_ringacc_ring_push_mem(struct k3_ring *ring, void *elem)
+{
+	void *elem_ptr;
+
+	elem_ptr = k3_ringacc_get_elm_addr(ring, ring->windex);
+
+	memcpy(elem_ptr, elem, (4 << ring->elm_size));
+
+	ring->windex = (ring->windex + 1) % ring->size;
+	ring->free--;
+	dbg_writel(1, &ring->rt->db);
+
+	k3_nav_dbg(ring->parent->dev, "ring_push_mem: free%d index%d\n",
+		   ring->free, ring->windex);
+
+	return 0;
+}
+
+static int k3_ringacc_ring_pop_mem(struct k3_ring *ring, void *elem)
+{
+	void *elem_ptr;
+
+	elem_ptr = k3_ringacc_get_elm_addr(ring, ring->rindex);
+
+	memcpy(elem, elem_ptr, (4 << ring->elm_size));
+
+	ring->rindex = (ring->rindex + 1) % ring->size;
+	ring->occ--;
+	dbg_writel(-1, &ring->rt->db);
+
+	k3_nav_dbg(ring->parent->dev, "ring_pop_mem: occ%d index%d pos_ptr%p\n",
+		   ring->occ, ring->rindex, elem_ptr);
+	return 0;
+}
+
+int k3_ringacc_ring_push(struct k3_ring *ring, void *elem)
+{
+	int ret = -EOPNOTSUPP;
+
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	k3_nav_dbg(ring->parent->dev, "ring_push: free%d index%d\n",
+		   ring->free, ring->windex);
+
+	if (k3_ringacc_ring_is_full(ring))
+		return -ENOMEM;
+
+	if (ring->ops && ring->ops->push_tail)
+		ret = ring->ops->push_tail(ring, elem);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_push);
+
+int k3_ringacc_ring_push_head(struct k3_ring *ring, void *elem)
+{
+	int ret = -EOPNOTSUPP;
+
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	k3_nav_dbg(ring->parent->dev, "ring_push_head: free%d index%d\n",
+		   ring->free, ring->windex);
+
+	if (k3_ringacc_ring_is_full(ring))
+		return -ENOMEM;
+
+	if (ring->ops && ring->ops->push_head)
+		ret = ring->ops->push_head(ring, elem);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_push_head);
+
+int k3_ringacc_ring_pop(struct k3_ring *ring, void *elem)
+{
+	int ret = -EOPNOTSUPP;
+
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	if (!ring->occ)
+		ring->occ = k3_ringacc_ring_get_occ(ring);
+
+	k3_nav_dbg(ring->parent->dev, "ring_pop: occ%d index%d\n",
+		   ring->occ, ring->rindex);
+
+	if (!ring->occ)
+		return -ENODATA;
+
+	if (ring->ops && ring->ops->pop_head)
+		ret = ring->ops->pop_head(ring, elem);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_pop);
+
+int k3_ringacc_ring_pop_tail(struct k3_ring *ring, void *elem)
+{
+	int ret = -EOPNOTSUPP;
+
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	if (!ring->occ)
+		ring->occ = k3_ringacc_ring_get_occ(ring);
+
+	k3_nav_dbg(ring->parent->dev, "ring_pop_tail: occ%d index%d\n",
+		   ring->occ, ring->rindex);
+
+	if (!ring->occ)
+		return -ENODATA;
+
+	if (ring->ops && ring->ops->pop_tail)
+		ret = ring->ops->pop_tail(ring, elem);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_pop_tail);
+
+struct k3_ringacc *of_k3_ringacc_get_by_phandle(struct device_node *np,
+						const char *property)
+{
+	struct device_node *ringacc_np;
+	struct k3_ringacc *ringacc = ERR_PTR(-EPROBE_DEFER);
+	struct k3_ringacc *entry;
+
+	ringacc_np = of_parse_phandle(np, property, 0);
+	if (!ringacc_np)
+		return ERR_PTR(-ENODEV);
+
+	mutex_lock(&k3_ringacc_list_lock);
+	list_for_each_entry(entry, &k3_ringacc_list, list)
+		if (entry->dev->of_node == ringacc_np) {
+			ringacc = entry;
+			break;
+		}
+	mutex_unlock(&k3_ringacc_list_lock);
+	of_node_put(ringacc_np);
+
+	return ringacc;
+}
+EXPORT_SYMBOL_GPL(of_k3_ringacc_get_by_phandle);
+
+static int k3_ringacc_probe_dt(struct k3_ringacc *ringacc)
+{
+	struct device_node *node = ringacc->dev->of_node;
+	struct device *dev = ringacc->dev;
+	struct platform_device *pdev = to_platform_device(dev);
+	int ret;
+
+	if (!node) {
+		dev_err(dev, "device tree info unavailable\n");
+		return -ENODEV;
+	}
+
+	ret = of_property_read_u32(node, "ti,num-rings", &ringacc->num_rings);
+	if (ret) {
+		dev_err(dev, "ti,num-rings read failure %d\n", ret);
+		return ret;
+	}
+
+	ringacc->dma_ring_reset_quirk =
+			of_property_read_bool(node, "ti,dma-ring-reset-quirk");
+
+	ringacc->tisci = ti_sci_get_by_phandle(node, "ti,sci");
+	if (IS_ERR(ringacc->tisci)) {
+		ret = PTR_ERR(ringacc->tisci);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "ti,sci read fail %d\n", ret);
+		ringacc->tisci = NULL;
+		return ret;
+	}
+
+	ret = of_property_read_u32(node, "ti,sci-dev-id",
+				   &ringacc->tisci_dev_id);
+	if (ret) {
+		dev_err(dev, "ti,sci-dev-id read fail %d\n", ret);
+		return ret;
+	}
+
+	pdev->id = ringacc->tisci_dev_id;
+
+	ringacc->rm_gp_range = devm_ti_sci_get_of_resource(ringacc->tisci, dev,
+						ringacc->tisci_dev_id,
+						"ti,sci-rm-range-gp-rings");
+	if (IS_ERR(ringacc->rm_gp_range)) {
+		dev_err(dev, "Failed to allocate MSI interrupts\n");
+		return PTR_ERR(ringacc->rm_gp_range);
+	}
+
+	return ti_sci_inta_msi_domain_alloc_irqs(ringacc->dev,
+						 ringacc->rm_gp_range);
+}
+
+static int k3_ringacc_probe(struct platform_device *pdev)
+{
+	struct k3_ringacc *ringacc;
+	void __iomem *base_fifo, *base_rt;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	int ret, i;
+
+	ringacc = devm_kzalloc(dev, sizeof(*ringacc), GFP_KERNEL);
+	if (!ringacc)
+		return -ENOMEM;
+
+	ringacc->dev = dev;
+	mutex_init(&ringacc->req_lock);
+
+	dev->msi_domain = of_msi_get_domain(dev, dev->of_node,
+					    DOMAIN_BUS_TI_SCI_INTA_MSI);
+	if (!dev->msi_domain) {
+		dev_err(dev, "Failed to get MSI domain\n");
+		return -EPROBE_DEFER;
+	}
+
+	ret = k3_ringacc_probe_dt(ringacc);
+	if (ret)
+		return ret;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rt");
+	base_rt = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base_rt))
+		return PTR_ERR(base_rt);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fifos");
+	base_fifo = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base_fifo))
+		return PTR_ERR(base_fifo);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "proxy_gcfg");
+	ringacc->proxy_gcfg = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ringacc->proxy_gcfg))
+		return PTR_ERR(ringacc->proxy_gcfg);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+					   "proxy_target");
+	ringacc->proxy_target_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ringacc->proxy_target_base))
+		return PTR_ERR(ringacc->proxy_target_base);
+
+	ringacc->num_proxies = dbg_readl(&ringacc->proxy_gcfg->config) &
+					 K3_RINGACC_PROXY_CFG_THREADS_MASK;
+
+	ringacc->rings = devm_kzalloc(dev,
+				      sizeof(*ringacc->rings) *
+				      ringacc->num_rings,
+				      GFP_KERNEL);
+	ringacc->rings_inuse = devm_kcalloc(dev,
+					    BITS_TO_LONGS(ringacc->num_rings),
+					    sizeof(unsigned long), GFP_KERNEL);
+	ringacc->proxy_inuse = devm_kcalloc(dev,
+					    BITS_TO_LONGS(ringacc->num_proxies),
+					    sizeof(unsigned long), GFP_KERNEL);
+
+	if (!ringacc->rings || !ringacc->rings_inuse || !ringacc->proxy_inuse)
+		return -ENOMEM;
+
+	for (i = 0; i < ringacc->num_rings; i++) {
+		ringacc->rings[i].rt = base_rt +
+				       K3_RINGACC_RT_REGS_STEP * i;
+		ringacc->rings[i].fifos = base_fifo +
+					  K3_RINGACC_FIFO_REGS_STEP * i;
+		ringacc->rings[i].parent = ringacc;
+		ringacc->rings[i].ring_id = i;
+		ringacc->rings[i].proxy_id = K3_RINGACC_PROXY_NOT_USED;
+	}
+	dev_set_drvdata(dev, ringacc);
+
+	ringacc->tisci_ring_ops = &ringacc->tisci->ops.rm_ring_ops;
+
+	pm_runtime_enable(dev);
+	ret = pm_runtime_get_sync(dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(dev);
+		dev_err(dev, "Failed to enable pm %d\n", ret);
+		goto err;
+	}
+
+	mutex_lock(&k3_ringacc_list_lock);
+	list_add_tail(&ringacc->list, &k3_ringacc_list);
+	mutex_unlock(&k3_ringacc_list_lock);
+
+	dev_info(dev, "Ring Accelerator probed rings:%u, gp-rings[%u,%u] sci-dev-id:%u\n",
+		 ringacc->num_rings,
+		 ringacc->rm_gp_range->desc[0].start,
+		 ringacc->rm_gp_range->desc[0].num,
+		 ringacc->tisci_dev_id);
+	dev_info(dev, "dma-ring-reset-quirk: %s\n",
+		 ringacc->dma_ring_reset_quirk ? "enabled" : "disabled");
+	dev_info(dev, "RA Proxy rev. %08x, num_proxies:%u\n",
+		 dbg_readl(&ringacc->proxy_gcfg->revision),
+		 ringacc->num_proxies);
+	return 0;
+
+err:
+	pm_runtime_disable(dev);
+	return ret;
+}
+
+static int k3_ringacc_remove(struct platform_device *pdev)
+{
+	struct k3_ringacc *ringacc = dev_get_drvdata(&pdev->dev);
+
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	mutex_lock(&k3_ringacc_list_lock);
+	list_del(&ringacc->list);
+	mutex_unlock(&k3_ringacc_list_lock);
+	return 0;
+}
+
+/* Match table for of_platform binding */
+static const struct of_device_id k3_ringacc_of_match[] = {
+	{ .compatible = "ti,am654-navss-ringacc", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, k3_ringacc_of_match);
+
+static struct platform_driver k3_ringacc_driver = {
+	.probe		= k3_ringacc_probe,
+	.remove		= k3_ringacc_remove,
+	.driver		= {
+		.name	= "k3-ringacc",
+		.of_match_table = k3_ringacc_of_match,
+	},
+};
+module_platform_driver(k3_ringacc_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("TI Ringacc driver for K3 SOCs");
+MODULE_AUTHOR("Grygorii Strashko <grygorii.strashko@ti.com>");
diff --git a/include/linux/soc/ti/k3-ringacc.h b/include/linux/soc/ti/k3-ringacc.h
new file mode 100644
index 000000000000..debffba48ac9
--- /dev/null
+++ b/include/linux/soc/ti/k3-ringacc.h
@@ -0,0 +1,262 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * K3 Ring Accelerator (RA) subsystem interface
+ *
+ * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
+ */
+
+#ifndef __SOC_TI_K3_RINGACC_API_H_
+#define __SOC_TI_K3_RINGACC_API_H_
+
+#include <linux/types.h>
+
+struct device_node;
+
+/**
+ * enum k3_ring_mode - &struct k3_ring_cfg mode
+ *
+ * RA ring operational modes
+ *
+ * @K3_RINGACC_RING_MODE_RING: Exposed Ring mode for SW direct access
+ * @K3_RINGACC_RING_MODE_MESSAGE: Messaging mode. Messaging mode requires
+ *	that all accesses to the queue must go through this IP so that all
+ *	accesses to the memory are controlled and ordered. This IP then
+ *	controls the entire state of the queue, and SW has no directly control,
+ *	such as through doorbells and cannot access the storage memory directly.
+ *	This is particularly useful when more than one SW or HW entity can be
+ *	the producer and/or consumer at the same time
+ * @K3_RINGACC_RING_MODE_CREDENTIALS: Credentials mode is message mode plus
+ *	stores credentials with each message, requiring the element size to be
+ *	doubled to fit the credentials. Any exposed memory should be protected
+ *	by a firewall from unwanted access
+ * @K3_RINGACC_RING_MODE_QM:  Queue manager mode. This takes the credentials
+ *	mode and adds packet length per element, along with additional read only
+ *	fields for element count and accumulated queue length. The QM mode only
+ *	operates with an 8 byte element size (any other element size is
+ *	illegal), and like in credentials mode each operation uses 2 element
+ *	slots to store the credentials and length fields
+ */
+enum k3_ring_mode {
+	K3_RINGACC_RING_MODE_RING = 0,
+	K3_RINGACC_RING_MODE_MESSAGE,
+	K3_RINGACC_RING_MODE_CREDENTIALS,
+	K3_RINGACC_RING_MODE_QM,
+	K3_RINGACC_RING_MODE_INVALID
+};
+
+/**
+ * enum k3_ring_size - &struct k3_ring_cfg elm_size
+ *
+ * RA ring element's sizes in bytes.
+ */
+enum k3_ring_size {
+	K3_RINGACC_RING_ELSIZE_4 = 0,
+	K3_RINGACC_RING_ELSIZE_8,
+	K3_RINGACC_RING_ELSIZE_16,
+	K3_RINGACC_RING_ELSIZE_32,
+	K3_RINGACC_RING_ELSIZE_64,
+	K3_RINGACC_RING_ELSIZE_128,
+	K3_RINGACC_RING_ELSIZE_256,
+	K3_RINGACC_RING_ELSIZE_INVALID
+};
+
+struct k3_ringacc;
+struct k3_ring;
+
+/**
+ * enum k3_ring_cfg - RA ring configuration structure
+ *
+ * @size: Ring size, number of elements
+ * @elm_size: Ring element size
+ * @mode: Ring operational mode
+ * @flags: Ring configuration flags. Possible values:
+ *	 @K3_RINGACC_RING_SHARED: when set allows to request the same ring
+ *	 few times. It's usable when the same ring is used as Free Host PD ring
+ *	 for different flows, for example.
+ *	 Note: Locking should be done by consumer if required
+ */
+struct k3_ring_cfg {
+	u32 size;
+	enum k3_ring_size elm_size;
+	enum k3_ring_mode mode;
+#define K3_RINGACC_RING_SHARED BIT(1)
+	u32 flags;
+};
+
+#define K3_RINGACC_RING_ID_ANY (-1)
+
+/**
+ * of_k3_ringacc_get_by_phandle - find a RA by phandle property
+ * @np: device node
+ * @propname: property name containing phandle on RA node
+ *
+ * Returns pointer on the RA - struct k3_ringacc
+ * or -ENODEV if not found,
+ * or -EPROBE_DEFER if not yet registered
+ */
+struct k3_ringacc *of_k3_ringacc_get_by_phandle(struct device_node *np,
+						const char *property);
+
+#define K3_RINGACC_RING_USE_PROXY BIT(1)
+
+/**
+ * k3_ringacc_request_ring - request ring from ringacc
+ * @ringacc: pointer on ringacc
+ * @id: ring id or K3_RINGACC_RING_ID_ANY for any general purpose ring
+ * @flags:
+ *	@K3_RINGACC_RING_USE_PROXY: if set - proxy will be allocated and
+ *		used to access ring memory. Sopported only for rings in
+ *		Message/Credentials/Queue mode.
+ *
+ * Returns pointer on the Ring - struct k3_ring
+ * or NULL in case of failure.
+ */
+struct k3_ring *k3_ringacc_request_ring(struct k3_ringacc *ringacc,
+					int id, u32 flags);
+
+/**
+ * k3_ringacc_ring_reset - ring reset
+ * @ring: pointer on Ring
+ *
+ * Resets ring internal state ((hw)occ, (hw)idx).
+ * TODO_GS: ? Ring can be reused without reconfiguration
+ */
+void k3_ringacc_ring_reset(struct k3_ring *ring);
+/**
+ * k3_ringacc_ring_reset - ring reset for DMA rings
+ * @ring: pointer on Ring
+ *
+ * Resets ring internal state ((hw)occ, (hw)idx). Should be used for rings
+ * which are read by K3 UDMA, like TX or Free Host PD rings.
+ */
+void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ);
+
+/**
+ * k3_ringacc_ring_free - ring free
+ * @ring: pointer on Ring
+ *
+ * Resets ring and free all alocated resources.
+ */
+int k3_ringacc_ring_free(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_get_ring_id - Get the Ring ID
+ * @ring: pointer on ring
+ *
+ * Returns the Ring ID
+ */
+u32 k3_ringacc_get_ring_id(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_get_ring_irq_num - Get the irq number for the ring
+ * @ring: pointer on ring
+ *
+ * Returns the interrupt number which can be used to request the interrupt
+ */
+int k3_ringacc_get_ring_irq_num(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_ring_cfg - ring configure
+ * @ring: pointer on ring
+ * @cfg: Ring configuration parameters (see &struct k3_ring_cfg)
+ *
+ * Configures ring, including ring memory allocation.
+ * Returns 0 on success, errno otherwise.
+ */
+int k3_ringacc_ring_cfg(struct k3_ring *ring, struct k3_ring_cfg *cfg);
+
+/**
+ * k3_ringacc_ring_get_size - get ring size
+ * @ring: pointer on ring
+ *
+ * Returns ring size in number of elements.
+ */
+u32 k3_ringacc_ring_get_size(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_ring_get_free - get free elements
+ * @ring: pointer on ring
+ *
+ * Returns number of free elements in the ring.
+ */
+u32 k3_ringacc_ring_get_free(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_ring_get_occ - get ring occupancy
+ * @ring: pointer on ring
+ *
+ * Returns total number of valid entries on the ring
+ */
+u32 k3_ringacc_ring_get_occ(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_ring_is_full - checks if ring is full
+ * @ring: pointer on ring
+ *
+ * Returns true if the ring is full
+ */
+u32 k3_ringacc_ring_is_full(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_ring_push - push element to the ring tail
+ * @ring: pointer on ring
+ * @elem: pointer on ring element buffer
+ *
+ * Push one ring element to the ring tail. Size of the ring element is
+ * determined by ring configuration &struct k3_ring_cfg elm_size.
+ *
+ * Returns 0 on success, errno otherwise.
+ */
+int k3_ringacc_ring_push(struct k3_ring *ring, void *elem);
+
+/**
+ * k3_ringacc_ring_pop - pop element from the ring head
+ * @ring: pointer on ring
+ * @elem: pointer on ring element buffer
+ *
+ * Push one ring element from the ring head. Size of the ring element is
+ * determined by ring configuration &struct k3_ring_cfg elm_size..
+ *
+ * Returns 0 on success, errno otherwise.
+ */
+int k3_ringacc_ring_pop(struct k3_ring *ring, void *elem);
+
+/**
+ * k3_ringacc_ring_push_head - push element to the ring head
+ * @ring: pointer on ring
+ * @elem: pointer on ring element buffer
+ *
+ * Push one ring element to the ring head. Size of the ring element is
+ * determined by ring configuration &struct k3_ring_cfg elm_size.
+ *
+ * Returns 0 on success, errno otherwise.
+ * Not Supported by ring modes: K3_RINGACC_RING_MODE_RING
+ */
+int k3_ringacc_ring_push_head(struct k3_ring *ring, void *elem);
+
+/**
+ * k3_ringacc_ring_pop_tail - pop element from the ring tail
+ * @ring: pointer on ring
+ * @elem: pointer on ring element buffer
+ *
+ * Push one ring element from the ring tail. Size of the ring element is
+ * determined by ring configuration &struct k3_ring_cfg elm_size.
+ *
+ * Returns 0 on success, errno otherwise.
+ * Not Supported by ring modes: K3_RINGACC_RING_MODE_RING
+ */
+int k3_ringacc_ring_pop_tail(struct k3_ring *ring, void *elem);
+
+u32 k3_ringacc_get_tisci_dev_id(struct k3_ring *ring);
+
+/**
+ * Debugging definitions
+ * TODO: might be removed
+ */
+#ifdef CONFIG_TI_K3_RINGACC_DEBUG
+void k3_ringacc_ring_dump(struct k3_ring *ring);
+#else
+static inline void k3_ringacc_ring_dump(struct k3_ring *ring) {};
+#endif
+
+#endif /* __SOC_TI_K3_RINGACC_API_H_ */