diff mbox

[v4] soc/imx: Add GPCv2 power gating driver

Message ID 20170301000916.32412-1-andrew.smirnov@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Andrey Smirnov March 1, 2017, 12:09 a.m. UTC
Add code allowing for control of various power domains managed by GPCv2
IP block found in i.MX7 series of SoCs. Power domains covered by this
patch are:

    - PCIE PHY
    - MIPI PHY
    - USB HSIC PHY
    - USB OTG1/2 PHY

Support for any other power domain controlled by GPC is not present, and
can be added at some later point.

Testing of this code was done against a PCIe driver.

Cc: yurovsky@gmail.com
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---

Changes since v3 (see [v3]):

	- Minor device tree bindings documentation fixes as per
          feedback from Rob Herring
	- Collect Acked-by from Rob

Changes since v2 (see [v2]):

	- Fix a critical bug where incorrect state of a bit was
          expected in a busy wait loop (bit set instead of bit
          cleared) imx7_gpc_pu_pgc_sw_pxx_req()

	- Add missing step (setting of PCR in GPC_PGC_nCTRL) in power
          down procedure

Changes since v1 (see [v1]):

	- Various small DT bindings description fixes as per feedback
          from Rob Herring


[v1] https://lkml.org/lkml/2017/2/6/554
[v2] https://lkml.org/lkml/2017/2/13/489
[v3] https://lkml.org/lkml/2017/2/20/338

 .../devicetree/bindings/power/fsl,imx-gpcv2.txt    |  71 ++++
 drivers/soc/imx/Makefile                           |   2 +-
 drivers/soc/imx/gpcv2.c                            | 397 +++++++++++++++++++++
 include/dt-bindings/power/imx7-power.h             |  18 +
 4 files changed, 487 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
 create mode 100644 drivers/soc/imx/gpcv2.c
 create mode 100644 include/dt-bindings/power/imx7-power.h

Comments

Shawn Guo March 8, 2017, 11:39 a.m. UTC | #1
On Tue, Feb 28, 2017 at 04:09:16PM -0800, Andrey Smirnov wrote:
> Add code allowing for control of various power domains managed by GPCv2

GPCv2, is it the name used in i.MX7 SoC manual?

> IP block found in i.MX7 series of SoCs. Power domains covered by this
> patch are:
> 
>     - PCIE PHY
>     - MIPI PHY
>     - USB HSIC PHY
>     - USB OTG1/2 PHY
> 
> Support for any other power domain controlled by GPC is not present, and
> can be added at some later point.
> 
> Testing of this code was done against a PCIe driver.
> 
> Cc: yurovsky@gmail.com
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Fabio Estevam <fabio.estevam@nxp.com>
> Cc: devicetree@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> Acked-by: Rob Herring <robh@kernel.org>
> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> ---
> 
> Changes since v3 (see [v3]):
> 
> 	- Minor device tree bindings documentation fixes as per
>           feedback from Rob Herring
> 	- Collect Acked-by from Rob
> 
> Changes since v2 (see [v2]):
> 
> 	- Fix a critical bug where incorrect state of a bit was
>           expected in a busy wait loop (bit set instead of bit
>           cleared) imx7_gpc_pu_pgc_sw_pxx_req()
> 
> 	- Add missing step (setting of PCR in GPC_PGC_nCTRL) in power
>           down procedure
> 
> Changes since v1 (see [v1]):
> 
> 	- Various small DT bindings description fixes as per feedback
>           from Rob Herring
> 
> 
> [v1] https://lkml.org/lkml/2017/2/6/554
> [v2] https://lkml.org/lkml/2017/2/13/489
> [v3] https://lkml.org/lkml/2017/2/20/338
> 
>  .../devicetree/bindings/power/fsl,imx-gpcv2.txt    |  71 ++++
>  drivers/soc/imx/Makefile                           |   2 +-
>  drivers/soc/imx/gpcv2.c                            | 397 +++++++++++++++++++++
>  include/dt-bindings/power/imx7-power.h             |  18 +

Please have fsl,imx-gpcv2.txt and imx7-power.h in a separate dt-bindings
patch, and attach Rob's ACK to it.

>  4 files changed, 487 insertions(+), 1 deletion(-)
>  create mode 100644 Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
>  create mode 100644 drivers/soc/imx/gpcv2.c
>  create mode 100644 include/dt-bindings/power/imx7-power.h
> 
> diff --git a/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt b/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
> new file mode 100644
> index 0000000..02f45c6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
> @@ -0,0 +1,71 @@
> +Freescale i.MX General Power Controller v2
> +==========================================
> +
> +The i.MX7S/D General Power Control (GPC) block contains Power Gating
> +Control (PGC) for various power domains.
> +
> +Required properties:
> +
> +- compatible: Should be "fsl,imx7d-gpc"
> +
> +- reg: should be register base and length as documented in the
> +  datasheet
> +
> +- interrupts: Should contain GPC interrupt request 1
> +
> +Power domains contained within GPC node are generic power domain
> +providers, documented in
> +Documentation/devicetree/bindings/power/power_domain.txt, which are
> +described as subnodes of the power gating controller 'pgc' node,
> +which, in turn, is expected to contain the following:
> +
> +Required properties:
> +
> +- reg: Power domain index. Valid values are defined in
> +  include/dt-bindings/power/imx7-power.h
> +
> +- #power-domain-cells: Should be 0
> +
> +Optional properties:
> +
> +- power-supply: Power supply used to power the domain
> +
> +Example:
> +
> +	gpc: gpc@303a0000 {
> +		compatible = "fsl,imx7d-gpc";
> +		reg = <0x303a0000 0x1000>;
> +		interrupt-controller;
> +		interrupts = <GIC_SPI 87 IRQ_TYPE_LEVEL_HIGH>;
> +		#interrupt-cells = <3>;
> +		interrupt-parent = <&intc>;
> +
> +		pgc {
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +
> +			pgc_pcie_phy: power-domain@3 {
> +				#power-domain-cells = <0>;
> +
> +				reg = <IMX7_POWER_DOMAIN_PCIE_PHY>;
> +				power-supply = <&reg_1p0d>;
> +			};
> +		};
> +	};
> +
> +
> +Specifying power domain for IP modules
> +======================================
> +
> +IP cores belonging to a power domain should contain a 'power-domains'
> +property that is a phandle for PGC node representing the domain.
> +
> +Example of a device that is part of the PCIE_PHY power domain:
> +
> +	pcie: pcie@33800000 {
> +	      reg = <0x33800000 0x4000>,
> +	            <0x4ff00000 0x80000>;
> +		/* ... */
> +		power-domains = <&pgc_pcie_phy>;
> +		/* ... */
> +	};
> diff --git a/drivers/soc/imx/Makefile b/drivers/soc/imx/Makefile
> index 35861f5..7bcc933 100644
> --- a/drivers/soc/imx/Makefile
> +++ b/drivers/soc/imx/Makefile
> @@ -1 +1 @@
> -obj-y += gpc.o
> +obj-y += gpc.o gpcv2.o
> diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c
> new file mode 100644
> index 0000000..20f0515
> --- /dev/null
> +++ b/drivers/soc/imx/gpcv2.c
> @@ -0,0 +1,397 @@
> +/*
> + * Copyright 2017 Impinj, Inc
> + * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
> + *
> + * Based on the code of analogus driver:
> + *
> + * Copyright 2015-2017 Pengutronix, Lucas Stach <kernel@pengutronix.de>
> + *
> + * The code contained herein is licensed under the GNU General Public
> + * License. You may obtain a copy of the GNU General Public License
> + * Version 2 or later at the following locations:
> + *
> + * http://www.opensource.org/licenses/gpl-license.html
> + * http://www.gnu.org/copyleft/gpl.html
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/io.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_domain.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +#include <dt-bindings/power/imx7-power.h>
> +
> +#define GPC_PGC_CPU_MAPPING	0xec
> +#define USB_HSIC_PHY_A7_DOMAIN	BIT(6)
> +#define USB_OTG2_PHY_A7_DOMAIN	BIT(5)
> +#define USB_OTG1_PHY_A7_DOMAIN	BIT(4)
> +#define PCIE_PHY_A7_DOMAIN	BIT(3)
> +#define MIPI_PHY_A7_DOMAIN	BIT(2)
> +
> +#define GPC_PU_PGC_SW_PUP_REQ	0xf8
> +#define GPC_PU_PGC_SW_PDN_REQ	0x104
> +#define USB_HSIC_PHY_SW_Pxx_REQ	BIT(4)
> +#define USB_OTG2_PHY_SW_Pxx_REQ	BIT(3)
> +#define USB_OTG1_PHY_SW_Pxx_REQ	BIT(2)
> +#define PCIE_PHY_SW_Pxx_REQ	BIT(1)
> +#define MIPI_PHY_SW_Pxx_REQ	BIT(0)
> +
> +#define GPC_MAX_REGISTER	0x1000
> +
> +#define GPC_PGC_nCTRL_PCR	BIT(0)
> +
> +struct imx7_pgc_domain {
> +	struct generic_pm_domain genpd;
> +	struct regmap *regmap;
> +	struct regulator *regulator;
> +
> +	unsigned int pgc_nctrl;
> +
> +	const struct {
> +		u32 pxx;
> +		u32 map;
> +	} bits;
> +
> +	const int voltage;
> +	struct device *dev;
> +};
> +
> +static int imx7_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain *genpd,
> +				      bool on)
> +{
> +	int ret = 0;
> +	unsigned long deadline;
> +	struct imx7_pgc_domain *domain = container_of(genpd,
> +						      struct imx7_pgc_domain,
> +						      genpd);
> +	unsigned int offset = (on) ?

Unnecessary parenthesis.

> +		GPC_PU_PGC_SW_PUP_REQ : GPC_PU_PGC_SW_PDN_REQ;
> +
> +	const bool has_regulator = !IS_ERR(domain->regulator);
> +	const bool enable_power_control = domain->pgc_nctrl && !on;

Reverse tree for variable declarations please.

> +
> +	regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
> +			   domain->bits.map, domain->bits.map);

Have a newline here.

> +	if (has_regulator && on) {
> +		ret = regulator_enable(domain->regulator);
> +		if (ret) {
> +			dev_err(domain->dev, "failed to enable regulator\n");
> +			goto unmap;
> +		}
> +	}
> +
> +	if (enable_power_control)
> +		regmap_update_bits(domain->regmap, domain->pgc_nctrl,
> +				   GPC_PGC_nCTRL_PCR, GPC_PGC_nCTRL_PCR);
> +
> +

One newline is good enough.

> +	regmap_update_bits(domain->regmap, offset,
> +			   domain->bits.pxx, domain->bits.pxx);

Have a newline here.

> +	/*
> +	 * As per "5.5.9.4 Example Code 4" in IMX7DRM.pdf wait
> +	 * for PUP_REQ/PDN_REQ bit to be cleared
> +	 */
> +	deadline = jiffies + msecs_to_jiffies(1);
> +	while (true) {
> +		u32 pxx_req;
> +
> +		regmap_read(domain->regmap, offset, &pxx_req);
> +
> +		if (!(pxx_req & domain->bits.pxx))
> +			break;
> +
> +		if (time_after(jiffies, deadline)) {
> +			dev_err(domain->dev, "falied to command PGC\n");
> +			ret = -ETIMEDOUT;
> +			/*
> +			 * If we were in a process of enabling a
> +			 * domain and failed we might as well disable
> +			 * the regulator we just enabled. And if it
> +			 * was the opposite situation and we failed to
> +			 * power down -- keep the regulator on
> +			 */
> +			on  = !on;

One space between on and =.

> +			break;
> +		}
> +
> +		cpu_relax();
> +	}
> +
> +	if (enable_power_control)
> +		regmap_update_bits(domain->regmap, domain->pgc_nctrl,
> +				   GPC_PGC_nCTRL_PCR, 0);
> +
> +	if (has_regulator && !on) {
> +		int err;
> +
> +		err = regulator_disable(domain->regulator);
> +		if (err)
> +			dev_err(domain->dev,
> +				"failed to disable regulator: %d\n", ret);
> +		/*
> +		 * Preserve earlier error code
> +		 */

/* One line comment */

> +		ret = ret ?: err;
> +	}
> +unmap:
> +	regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
> +			   domain->bits.map, 0);
> +	return ret;
> +}
> +
> +static int imx7_gpc_pu_pgc_sw_pup_req(struct generic_pm_domain *genpd)
> +{
> +	return imx7_gpc_pu_pgc_sw_pxx_req(genpd, true);
> +}
> +
> +static int imx7_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain *genpd)
> +{
> +	return imx7_gpc_pu_pgc_sw_pxx_req(genpd, false);
> +}
> +
> +static struct imx7_pgc_domain imx7_pgc_domains[] = {
> +	[IMX7_POWER_DOMAIN_USB_HSIC_PHY] = {
> +		.genpd = {
> +			.name      = "usb-hsic-phy",
> +			.power_on  = imx7_gpc_pu_pgc_sw_pup_req,
> +			.power_off = imx7_gpc_pu_pgc_sw_pdn_req,
> +		},
> +		.bits  = {
> +			.pxx = USB_HSIC_PHY_SW_Pxx_REQ,
> +			.map = USB_HSIC_PHY_A7_DOMAIN,
> +		},
> +		.voltage   = 1200000,
> +		.pgc_nctrl = 0x0d00,
> +	},
> +
> +	[IMX7_POWER_DOMAIN_USB_OTG2_PHY] = {
> +		.genpd = {
> +			.name      = "usb-otg2-phy",
> +			.power_on  = imx7_gpc_pu_pgc_sw_pup_req,
> +			.power_off = imx7_gpc_pu_pgc_sw_pdn_req,
> +		},
> +		.bits  = {
> +			.pxx = USB_OTG2_PHY_SW_Pxx_REQ,
> +			.map = USB_OTG2_PHY_A7_DOMAIN,
> +		},
> +	},
> +
> +	[IMX7_POWER_DOMAIN_USB_OTG1_PHY] = {
> +		.genpd = {
> +			.name      = "usb-otg1-phy",
> +			.power_on  = imx7_gpc_pu_pgc_sw_pup_req,
> +			.power_off = imx7_gpc_pu_pgc_sw_pdn_req,
> +		},
> +		.bits  = {
> +			.pxx = USB_OTG1_PHY_SW_Pxx_REQ,
> +			.map = USB_OTG1_PHY_A7_DOMAIN,
> +		},
> +	},
> +
> +	[IMX7_POWER_DOMAIN_PCIE_PHY] = {
> +		.genpd = {
> +			.name      = "pcie-phy",
> +			.power_on  = imx7_gpc_pu_pgc_sw_pup_req,
> +			.power_off = imx7_gpc_pu_pgc_sw_pdn_req,
> +		},
> +		.bits  = {
> +			.pxx = PCIE_PHY_SW_Pxx_REQ,
> +			.map = PCIE_PHY_A7_DOMAIN,
> +		},
> +		.voltage   = 1000000,
> +		.pgc_nctrl = 0x0c40,
> +	},
> +
> +	[IMX7_POWER_DOMAIN_MIPI_PHY] = {
> +		.genpd = {
> +			.name      = "mipi-phy",
> +			.power_on  = imx7_gpc_pu_pgc_sw_pup_req,
> +			.power_off = imx7_gpc_pu_pgc_sw_pdn_req,

So we need to do this hook setup for every single power domain, right?
If so, can we do it with for_each_child_of_node() loop in
imx_gpcv2_probe() function?

> +		},
> +		.bits  = {
> +			.pxx = MIPI_PHY_SW_Pxx_REQ,
> +			.map = MIPI_PHY_A7_DOMAIN,
> +		},
> +		.voltage   = 1000000,
> +		.pgc_nctrl = 0x0c00,
> +	},
> +};
> +
> +static int imx7_pgc_domain_probe(struct platform_device *pdev)
> +{
> +	int ret;
> +	struct imx7_pgc_domain *domain = pdev->dev.platform_data;

Reverse tree.

> +
> +	if (!IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS))
> +		return 0;

We should probably check the dependency with Kconfig?

> +
> +	domain->dev = &pdev->dev;
> +
> +	ret = pm_genpd_init(&domain->genpd, NULL, true);
> +	if (ret) {
> +		dev_err(domain->dev, "Failed to init power domain\n");
> +		return ret;
> +	}
> +
> +	domain->regulator = devm_regulator_get_optional(domain->dev, "power");
> +	if (IS_ERR(domain->regulator)  &&

One space before &&.

> +	    PTR_ERR(domain->regulator) != -ENODEV) {
> +		dev_err(domain->dev, "Failed to get domain's regulator\n");
> +		return PTR_ERR(domain->regulator);
> +	}
> +
> +	if (!IS_ERR(domain->regulator)) {
> +		WARN_ON(!domain->voltage);

Do we want to continue calling regulator_set_voltage() below?  Or should
we stop probing right here?

> +		regulator_set_voltage(domain->regulator,
> +				      domain->voltage, domain->voltage);
> +	}
> +
> +	ret = of_genpd_add_provider_simple(domain->dev->of_node,
> +					   &domain->genpd);
> +	if (ret) {
> +		dev_err(domain->dev, "Failed to add genpd provider\n");
> +		pm_genpd_remove(&domain->genpd);
> +	}
> +
> +	return ret;
> +}
> +
> +static int imx7_pgc_domain_remove(struct platform_device *pdev)
> +{
> +	struct imx7_pgc_domain *domain = pdev->dev.platform_data;
> +
> +	if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
> +		of_genpd_del_provider(domain->dev->of_node);
> +		pm_genpd_remove(&domain->genpd);
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct platform_device_id imx7_pgc_domain_id[] = {
> +	{ "imx7-pgc-domain", },
> +	{ },
> +};
> +
> +static struct platform_driver imx7_pgc_domain_driver = {
> +	.driver = {
> +		.name = "imx7-pgc",
> +	},
> +	.probe    = imx7_pgc_domain_probe,
> +	.remove   = imx7_pgc_domain_remove,
> +	.id_table = imx7_pgc_domain_id,
> +};
> +builtin_platform_driver(imx7_pgc_domain_driver)
> +
> +static bool imx_gpcv2_readable_reg(struct device *dev, unsigned int reg)
> +{
> +	return reg % 4 == 0 &&
> +	       reg <= GPC_MAX_REGISTER;
> +}
> +
> +static bool imx_gpcv2_volatile_reg(struct device *dev, unsigned int reg)
> +{
> +	return reg == GPC_PU_PGC_SW_PUP_REQ ||
> +	       reg == GPC_PU_PGC_SW_PDN_REQ;
> +}
> +
> +static int imx_gpcv2_probe(struct platform_device *pdev)
> +{
> +	int ret;
> +	void __iomem *base;
> +	struct resource *res;
> +	struct regmap *regmap;
> +	struct device *dev = &pdev->dev;
> +	struct device_node *pgc_np, *np;

Reverse tree.

> +
> +	static const struct regmap_config regmap_config = {
> +		.cache_type	= REGCACHE_FLAT,
> +		.reg_bits	= 32,
> +		.val_bits	= 32,
> +		.reg_stride	= 4,
> +
> +		.readable_reg	= imx_gpcv2_readable_reg,
> +		.volatile_reg	= imx_gpcv2_volatile_reg,
> +
> +		.max_register	= GPC_MAX_REGISTER,
> +	};
> +
> +	pgc_np = of_get_child_by_name(dev->of_node, "pgc");
> +	if (!pgc_np) {
> +		dev_err(dev, "No power domains specified in DT\n");
> +		return -EINVAL;
> +	}
> +
> +	res  = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(base))
> +		return PTR_ERR(base);
> +
> +	regmap = devm_regmap_init_mmio(dev, base, &regmap_config);
> +	if (IS_ERR(regmap)) {
> +		ret = PTR_ERR(regmap);
> +		dev_err(dev, "failed to init regmap\n");
> +		return ret;

You either want to print 'ret' in error message or you can return
PTR_ERR(regmap) directly.

> +	}
> +
> +	for_each_child_of_node(pgc_np, np) {
> +		u32 domain_index;
> +		struct platform_device *pd_pdev;
> +		struct imx7_pgc_domain *domain;

Reverse tree.

> +
> +		ret = of_property_read_u32(np, "reg", &domain_index);
> +		if (ret) {
> +			dev_err(dev, "Failed to read 'reg' property\n");
> +			of_node_put(np);
> +			return ret;
> +		}
> +
> +		if (domain_index >= ARRAY_SIZE(imx7_pgc_domains)) {
> +			dev_warn(dev,
> +				 "Domain index %d is out of bounds\n",
> +				 domain_index);
> +			continue;
> +		}
> +
> +		domain = &imx7_pgc_domains[domain_index];
> +		domain->regmap = regmap;
> +
> +		pd_pdev = platform_device_alloc("imx7-pgc-domain",
> +						domain_index);
> +		if (!pd_pdev) {
> +			dev_err(dev, "Failed to allocate platform device\n");
> +			of_node_put(np);
> +			return -ENOMEM;
> +		}
> +
> +		pd_pdev->dev.platform_data = domain;
> +		pd_pdev->dev.parent = dev;
> +		pd_pdev->dev.of_node = np;
> +
> +		ret = platform_device_add(pd_pdev);
> +		if (ret) {
> +			platform_device_put(pd_pdev);
> +			of_node_put(np);
> +			return ret;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id imx_gpcv2_dt_ids[] = {
> +	{ .compatible = "fsl,imx7d-gpc" },
> +	{ }
> +};
> +
> +static struct platform_driver imx_gpc_driver = {
> +	.driver = {
> +		.name = "imx-gpcv2",
> +		.of_match_table = imx_gpcv2_dt_ids,
> +	},
> +	.probe = imx_gpcv2_probe,
> +};
> +builtin_platform_driver(imx_gpc_driver)
> diff --git a/include/dt-bindings/power/imx7-power.h b/include/dt-bindings/power/imx7-power.h
> new file mode 100644
> index 0000000..24dde62
> --- /dev/null
> +++ b/include/dt-bindings/power/imx7-power.h
> @@ -0,0 +1,18 @@
> +/*
> + *  Copyright © 2017 Impinj
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#ifndef __DT_BINDINGS_ARM_IMX7_POWER_H__
> +#define __DT_BINDINGS_ARM_IMX7_POWER_H__

Drop 'ARM' from there.

Shawn

> +
> +#define IMX7_POWER_DOMAIN_USB_HSIC_PHY	0
> +#define IMX7_POWER_DOMAIN_USB_OTG2_PHY	1
> +#define IMX7_POWER_DOMAIN_USB_OTG1_PHY	2
> +#define IMX7_POWER_DOMAIN_PCIE_PHY	3
> +#define IMX7_POWER_DOMAIN_MIPI_PHY	4
> +
> +#endif
> -- 
> 2.9.3
>
Andrey Smirnov March 10, 2017, 5 a.m. UTC | #2
On Wed, Mar 8, 2017 at 3:39 AM, Shawn Guo <shawnguo@kernel.org> wrote:
> On Tue, Feb 28, 2017 at 04:09:16PM -0800, Andrey Smirnov wrote:
>> Add code allowing for control of various power domains managed by GPCv2
>
> GPCv2, is it the name used in i.MX7 SoC manual?

No, the manual refers to it as GPC. GPCv2 came from already existing
irqchip driver

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/drivers/irqchip/irq-imx-gpcv2.c?id=refs/tags/v4.11-rc1

Plus, I think, there were a number of LKML patch submission threads
where that IP block was referred to as as GPCv2 by Freescale devs.

>
>> IP block found in i.MX7 series of SoCs. Power domains covered by this
>> patch are:
>>
>>     - PCIE PHY
>>     - MIPI PHY
>>     - USB HSIC PHY
>>     - USB OTG1/2 PHY
>>
>> Support for any other power domain controlled by GPC is not present, and
>> can be added at some later point.
>>
>> Testing of this code was done against a PCIe driver.
>>
>> Cc: yurovsky@gmail.com
>> Cc: Lucas Stach <l.stach@pengutronix.de>
>> Cc: Rob Herring <robh+dt@kernel.org>
>> Cc: Mark Rutland <mark.rutland@arm.com>
>> Cc: Fabio Estevam <fabio.estevam@nxp.com>
>> Cc: devicetree@vger.kernel.org
>> Cc: linux-arm-kernel@lists.infradead.org
>> Cc: linux-kernel@vger.kernel.org
>> Acked-by: Rob Herring <robh@kernel.org>
>> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
>> ---
>>
>> Changes since v3 (see [v3]):
>>
>>       - Minor device tree bindings documentation fixes as per
>>           feedback from Rob Herring
>>       - Collect Acked-by from Rob
>>
>> Changes since v2 (see [v2]):
>>
>>       - Fix a critical bug where incorrect state of a bit was
>>           expected in a busy wait loop (bit set instead of bit
>>           cleared) imx7_gpc_pu_pgc_sw_pxx_req()
>>
>>       - Add missing step (setting of PCR in GPC_PGC_nCTRL) in power
>>           down procedure
>>
>> Changes since v1 (see [v1]):
>>
>>       - Various small DT bindings description fixes as per feedback
>>           from Rob Herring
>>
>>
>> [v1] https://lkml.org/lkml/2017/2/6/554
>> [v2] https://lkml.org/lkml/2017/2/13/489
>> [v3] https://lkml.org/lkml/2017/2/20/338
>>
>>  .../devicetree/bindings/power/fsl,imx-gpcv2.txt    |  71 ++++
>>  drivers/soc/imx/Makefile                           |   2 +-
>>  drivers/soc/imx/gpcv2.c                            | 397 +++++++++++++++++++++
>>  include/dt-bindings/power/imx7-power.h             |  18 +
>
> Please have fsl,imx-gpcv2.txt and imx7-power.h in a separate dt-bindings
> patch, and attach Rob's ACK to it.

OK, will do in v4.

>
>>  4 files changed, 487 insertions(+), 1 deletion(-)
>>  create mode 100644 Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
>>  create mode 100644 drivers/soc/imx/gpcv2.c
>>  create mode 100644 include/dt-bindings/power/imx7-power.h
>>
>> diff --git a/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt b/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
>> new file mode 100644
>> index 0000000..02f45c6
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
>> @@ -0,0 +1,71 @@
>> +Freescale i.MX General Power Controller v2
>> +==========================================
>> +
>> +The i.MX7S/D General Power Control (GPC) block contains Power Gating
>> +Control (PGC) for various power domains.
>> +
>> +Required properties:
>> +
>> +- compatible: Should be "fsl,imx7d-gpc"
>> +
>> +- reg: should be register base and length as documented in the
>> +  datasheet
>> +
>> +- interrupts: Should contain GPC interrupt request 1
>> +
>> +Power domains contained within GPC node are generic power domain
>> +providers, documented in
>> +Documentation/devicetree/bindings/power/power_domain.txt, which are
>> +described as subnodes of the power gating controller 'pgc' node,
>> +which, in turn, is expected to contain the following:
>> +
>> +Required properties:
>> +
>> +- reg: Power domain index. Valid values are defined in
>> +  include/dt-bindings/power/imx7-power.h
>> +
>> +- #power-domain-cells: Should be 0
>> +
>> +Optional properties:
>> +
>> +- power-supply: Power supply used to power the domain
>> +
>> +Example:
>> +
>> +     gpc: gpc@303a0000 {
>> +             compatible = "fsl,imx7d-gpc";
>> +             reg = <0x303a0000 0x1000>;
>> +             interrupt-controller;
>> +             interrupts = <GIC_SPI 87 IRQ_TYPE_LEVEL_HIGH>;
>> +             #interrupt-cells = <3>;
>> +             interrupt-parent = <&intc>;
>> +
>> +             pgc {
>> +                     #address-cells = <1>;
>> +                     #size-cells = <0>;
>> +
>> +                     pgc_pcie_phy: power-domain@3 {
>> +                             #power-domain-cells = <0>;
>> +
>> +                             reg = <IMX7_POWER_DOMAIN_PCIE_PHY>;
>> +                             power-supply = <&reg_1p0d>;
>> +                     };
>> +             };
>> +     };
>> +
>> +
>> +Specifying power domain for IP modules
>> +======================================
>> +
>> +IP cores belonging to a power domain should contain a 'power-domains'
>> +property that is a phandle for PGC node representing the domain.
>> +
>> +Example of a device that is part of the PCIE_PHY power domain:
>> +
>> +     pcie: pcie@33800000 {
>> +           reg = <0x33800000 0x4000>,
>> +                 <0x4ff00000 0x80000>;
>> +             /* ... */
>> +             power-domains = <&pgc_pcie_phy>;
>> +             /* ... */
>> +     };
>> diff --git a/drivers/soc/imx/Makefile b/drivers/soc/imx/Makefile
>> index 35861f5..7bcc933 100644
>> --- a/drivers/soc/imx/Makefile
>> +++ b/drivers/soc/imx/Makefile
>> @@ -1 +1 @@
>> -obj-y += gpc.o
>> +obj-y += gpc.o gpcv2.o
>> diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c
>> new file mode 100644
>> index 0000000..20f0515
>> --- /dev/null
>> +++ b/drivers/soc/imx/gpcv2.c
>> @@ -0,0 +1,397 @@
>> +/*
>> + * Copyright 2017 Impinj, Inc
>> + * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
>> + *
>> + * Based on the code of analogus driver:
>> + *
>> + * Copyright 2015-2017 Pengutronix, Lucas Stach <kernel@pengutronix.de>
>> + *
>> + * The code contained herein is licensed under the GNU General Public
>> + * License. You may obtain a copy of the GNU General Public License
>> + * Version 2 or later at the following locations:
>> + *
>> + * http://www.opensource.org/licenses/gpl-license.html
>> + * http://www.gnu.org/copyleft/gpl.html
>> + */
>> +
>> +#include <linux/clk.h>
>> +#include <linux/delay.h>
>> +#include <linux/io.h>
>> +#include <linux/of_device.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/pm_domain.h>
>> +#include <linux/regmap.h>
>> +#include <linux/regulator/consumer.h>
>> +#include <dt-bindings/power/imx7-power.h>
>> +
>> +#define GPC_PGC_CPU_MAPPING  0xec
>> +#define USB_HSIC_PHY_A7_DOMAIN       BIT(6)
>> +#define USB_OTG2_PHY_A7_DOMAIN       BIT(5)
>> +#define USB_OTG1_PHY_A7_DOMAIN       BIT(4)
>> +#define PCIE_PHY_A7_DOMAIN   BIT(3)
>> +#define MIPI_PHY_A7_DOMAIN   BIT(2)
>> +
>> +#define GPC_PU_PGC_SW_PUP_REQ        0xf8
>> +#define GPC_PU_PGC_SW_PDN_REQ        0x104
>> +#define USB_HSIC_PHY_SW_Pxx_REQ      BIT(4)
>> +#define USB_OTG2_PHY_SW_Pxx_REQ      BIT(3)
>> +#define USB_OTG1_PHY_SW_Pxx_REQ      BIT(2)
>> +#define PCIE_PHY_SW_Pxx_REQ  BIT(1)
>> +#define MIPI_PHY_SW_Pxx_REQ  BIT(0)
>> +
>> +#define GPC_MAX_REGISTER     0x1000
>> +
>> +#define GPC_PGC_nCTRL_PCR    BIT(0)
>> +
>> +struct imx7_pgc_domain {
>> +     struct generic_pm_domain genpd;
>> +     struct regmap *regmap;
>> +     struct regulator *regulator;
>> +
>> +     unsigned int pgc_nctrl;
>> +
>> +     const struct {
>> +             u32 pxx;
>> +             u32 map;
>> +     } bits;
>> +
>> +     const int voltage;
>> +     struct device *dev;
>> +};
>> +
>> +static int imx7_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain *genpd,
>> +                                   bool on)
>> +{
>> +     int ret = 0;
>> +     unsigned long deadline;
>> +     struct imx7_pgc_domain *domain = container_of(genpd,
>> +                                                   struct imx7_pgc_domain,
>> +                                                   genpd);
>> +     unsigned int offset = (on) ?
>
> Unnecessary parenthesis.

Will fix in v4.

>
>> +             GPC_PU_PGC_SW_PUP_REQ : GPC_PU_PGC_SW_PDN_REQ;
>> +
>> +     const bool has_regulator = !IS_ERR(domain->regulator);
>> +     const bool enable_power_control = domain->pgc_nctrl && !on;
>
> Reverse tree for variable declarations please.

Ditto.

>
>> +
>> +     regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
>> +                        domain->bits.map, domain->bits.map);
>
> Have a newline here.

Ditto.

>
>> +     if (has_regulator && on) {
>> +             ret = regulator_enable(domain->regulator);
>> +             if (ret) {
>> +                     dev_err(domain->dev, "failed to enable regulator\n");
>> +                     goto unmap;
>> +             }
>> +     }
>> +
>> +     if (enable_power_control)
>> +             regmap_update_bits(domain->regmap, domain->pgc_nctrl,
>> +                                GPC_PGC_nCTRL_PCR, GPC_PGC_nCTRL_PCR);
>> +
>> +
>
> One newline is good enough.

Ditto.

>
>> +     regmap_update_bits(domain->regmap, offset,
>> +                        domain->bits.pxx, domain->bits.pxx);
>
> Have a newline here.

OK.

>
>> +     /*
>> +      * As per "5.5.9.4 Example Code 4" in IMX7DRM.pdf wait
>> +      * for PUP_REQ/PDN_REQ bit to be cleared
>> +      */
>> +     deadline = jiffies + msecs_to_jiffies(1);
>> +     while (true) {
>> +             u32 pxx_req;
>> +
>> +             regmap_read(domain->regmap, offset, &pxx_req);
>> +
>> +             if (!(pxx_req & domain->bits.pxx))
>> +                     break;
>> +
>> +             if (time_after(jiffies, deadline)) {
>> +                     dev_err(domain->dev, "falied to command PGC\n");
>> +                     ret = -ETIMEDOUT;
>> +                     /*
>> +                      * If we were in a process of enabling a
>> +                      * domain and failed we might as well disable
>> +                      * the regulator we just enabled. And if it
>> +                      * was the opposite situation and we failed to
>> +                      * power down -- keep the regulator on
>> +                      */
>> +                     on  = !on;
>
> One space between on and =.

OK

>
>> +                     break;
>> +             }
>> +
>> +             cpu_relax();
>> +     }
>> +
>> +     if (enable_power_control)
>> +             regmap_update_bits(domain->regmap, domain->pgc_nctrl,
>> +                                GPC_PGC_nCTRL_PCR, 0);
>> +
>> +     if (has_regulator && !on) {
>> +             int err;
>> +
>> +             err = regulator_disable(domain->regulator);
>> +             if (err)
>> +                     dev_err(domain->dev,
>> +                             "failed to disable regulator: %d\n", ret);
>> +             /*
>> +              * Preserve earlier error code
>> +              */
>
> /* One line comment */

OK

>
>> +             ret = ret ?: err;
>> +     }
>> +unmap:
>> +     regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
>> +                        domain->bits.map, 0);
>> +     return ret;
>> +}
>> +
>> +static int imx7_gpc_pu_pgc_sw_pup_req(struct generic_pm_domain *genpd)
>> +{
>> +     return imx7_gpc_pu_pgc_sw_pxx_req(genpd, true);
>> +}
>> +
>> +static int imx7_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain *genpd)
>> +{
>> +     return imx7_gpc_pu_pgc_sw_pxx_req(genpd, false);
>> +}
>> +
>> +static struct imx7_pgc_domain imx7_pgc_domains[] = {
>> +     [IMX7_POWER_DOMAIN_USB_HSIC_PHY] = {
>> +             .genpd = {
>> +                     .name      = "usb-hsic-phy",
>> +                     .power_on  = imx7_gpc_pu_pgc_sw_pup_req,
>> +                     .power_off = imx7_gpc_pu_pgc_sw_pdn_req,
>> +             },
>> +             .bits  = {
>> +                     .pxx = USB_HSIC_PHY_SW_Pxx_REQ,
>> +                     .map = USB_HSIC_PHY_A7_DOMAIN,
>> +             },
>> +             .voltage   = 1200000,
>> +             .pgc_nctrl = 0x0d00,
>> +     },
>> +
>> +     [IMX7_POWER_DOMAIN_USB_OTG2_PHY] = {
>> +             .genpd = {
>> +                     .name      = "usb-otg2-phy",
>> +                     .power_on  = imx7_gpc_pu_pgc_sw_pup_req,
>> +                     .power_off = imx7_gpc_pu_pgc_sw_pdn_req,
>> +             },
>> +             .bits  = {
>> +                     .pxx = USB_OTG2_PHY_SW_Pxx_REQ,
>> +                     .map = USB_OTG2_PHY_A7_DOMAIN,
>> +             },
>> +     },
>> +
>> +     [IMX7_POWER_DOMAIN_USB_OTG1_PHY] = {
>> +             .genpd = {
>> +                     .name      = "usb-otg1-phy",
>> +                     .power_on  = imx7_gpc_pu_pgc_sw_pup_req,
>> +                     .power_off = imx7_gpc_pu_pgc_sw_pdn_req,
>> +             },
>> +             .bits  = {
>> +                     .pxx = USB_OTG1_PHY_SW_Pxx_REQ,
>> +                     .map = USB_OTG1_PHY_A7_DOMAIN,
>> +             },
>> +     },
>> +
>> +     [IMX7_POWER_DOMAIN_PCIE_PHY] = {
>> +             .genpd = {
>> +                     .name      = "pcie-phy",
>> +                     .power_on  = imx7_gpc_pu_pgc_sw_pup_req,
>> +                     .power_off = imx7_gpc_pu_pgc_sw_pdn_req,
>> +             },
>> +             .bits  = {
>> +                     .pxx = PCIE_PHY_SW_Pxx_REQ,
>> +                     .map = PCIE_PHY_A7_DOMAIN,
>> +             },
>> +             .voltage   = 1000000,
>> +             .pgc_nctrl = 0x0c40,
>> +     },
>> +
>> +     [IMX7_POWER_DOMAIN_MIPI_PHY] = {
>> +             .genpd = {
>> +                     .name      = "mipi-phy",
>> +                     .power_on  = imx7_gpc_pu_pgc_sw_pup_req,
>> +                     .power_off = imx7_gpc_pu_pgc_sw_pdn_req,
>
> So we need to do this hook setup for every single power domain, right?
> If so, can we do it with for_each_child_of_node() loop in
> imx_gpcv2_probe() function?

Yes for both, will do in v4.

>
>> +             },
>> +             .bits  = {
>> +                     .pxx = MIPI_PHY_SW_Pxx_REQ,
>> +                     .map = MIPI_PHY_A7_DOMAIN,
>> +             },
>> +             .voltage   = 1000000,
>> +             .pgc_nctrl = 0x0c00,
>> +     },
>> +};
>> +
>> +static int imx7_pgc_domain_probe(struct platform_device *pdev)
>> +{
>> +     int ret;
>> +     struct imx7_pgc_domain *domain = pdev->dev.platform_data;
>
> Reverse tree.

OK

>
>> +
>> +     if (!IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS))
>> +             return 0;
>
> We should probably check the dependency with Kconfig?
>

Agreed. Will fix in v4.

>> +
>> +     domain->dev = &pdev->dev;
>> +
>> +     ret = pm_genpd_init(&domain->genpd, NULL, true);
>> +     if (ret) {
>> +             dev_err(domain->dev, "Failed to init power domain\n");
>> +             return ret;
>> +     }
>> +
>> +     domain->regulator = devm_regulator_get_optional(domain->dev, "power");
>> +     if (IS_ERR(domain->regulator)  &&
>
> One space before &&.

OK

>
>> +         PTR_ERR(domain->regulator) != -ENODEV) {
>> +             dev_err(domain->dev, "Failed to get domain's regulator\n");
>> +             return PTR_ERR(domain->regulator);
>> +     }
>> +
>> +     if (!IS_ERR(domain->regulator)) {
>> +             WARN_ON(!domain->voltage);
>
> Do we want to continue calling regulator_set_voltage() below?  Or should
> we stop probing right here?

I can't think of a reason to continue probing. Will change in v4.

>
>> +             regulator_set_voltage(domain->regulator,
>> +                                   domain->voltage, domain->voltage);
>> +     }
>> +
>> +     ret = of_genpd_add_provider_simple(domain->dev->of_node,
>> +                                        &domain->genpd);
>> +     if (ret) {
>> +             dev_err(domain->dev, "Failed to add genpd provider\n");
>> +             pm_genpd_remove(&domain->genpd);
>> +     }
>> +
>> +     return ret;
>> +}
>> +
>> +static int imx7_pgc_domain_remove(struct platform_device *pdev)
>> +{
>> +     struct imx7_pgc_domain *domain = pdev->dev.platform_data;
>> +
>> +     if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
>> +             of_genpd_del_provider(domain->dev->of_node);
>> +             pm_genpd_remove(&domain->genpd);
>> +     }
>> +
>> +     return 0;
>> +}
>> +
>> +static const struct platform_device_id imx7_pgc_domain_id[] = {
>> +     { "imx7-pgc-domain", },
>> +     { },
>> +};
>> +
>> +static struct platform_driver imx7_pgc_domain_driver = {
>> +     .driver = {
>> +             .name = "imx7-pgc",
>> +     },
>> +     .probe    = imx7_pgc_domain_probe,
>> +     .remove   = imx7_pgc_domain_remove,
>> +     .id_table = imx7_pgc_domain_id,
>> +};
>> +builtin_platform_driver(imx7_pgc_domain_driver)
>> +
>> +static bool imx_gpcv2_readable_reg(struct device *dev, unsigned int reg)
>> +{
>> +     return reg % 4 == 0 &&
>> +            reg <= GPC_MAX_REGISTER;
>> +}
>> +
>> +static bool imx_gpcv2_volatile_reg(struct device *dev, unsigned int reg)
>> +{
>> +     return reg == GPC_PU_PGC_SW_PUP_REQ ||
>> +            reg == GPC_PU_PGC_SW_PDN_REQ;
>> +}
>> +
>> +static int imx_gpcv2_probe(struct platform_device *pdev)
>> +{
>> +     int ret;
>> +     void __iomem *base;
>> +     struct resource *res;
>> +     struct regmap *regmap;
>> +     struct device *dev = &pdev->dev;
>> +     struct device_node *pgc_np, *np;
>
> Reverse tree.

OK

>
>> +
>> +     static const struct regmap_config regmap_config = {
>> +             .cache_type     = REGCACHE_FLAT,
>> +             .reg_bits       = 32,
>> +             .val_bits       = 32,
>> +             .reg_stride     = 4,
>> +
>> +             .readable_reg   = imx_gpcv2_readable_reg,
>> +             .volatile_reg   = imx_gpcv2_volatile_reg,
>> +
>> +             .max_register   = GPC_MAX_REGISTER,
>> +     };
>> +
>> +     pgc_np = of_get_child_by_name(dev->of_node, "pgc");
>> +     if (!pgc_np) {
>> +             dev_err(dev, "No power domains specified in DT\n");
>> +             return -EINVAL;
>> +     }
>> +
>> +     res  = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +     base = devm_ioremap_resource(dev, res);
>> +     if (IS_ERR(base))
>> +             return PTR_ERR(base);
>> +
>> +     regmap = devm_regmap_init_mmio(dev, base, &regmap_config);
>> +     if (IS_ERR(regmap)) {
>> +             ret = PTR_ERR(regmap);
>> +             dev_err(dev, "failed to init regmap\n");
>> +             return ret;
>
> You either want to print 'ret' in error message or you can return
> PTR_ERR(regmap) directly.

OK, will do former in v4.

>
>> +     }
>> +
>> +     for_each_child_of_node(pgc_np, np) {
>> +             u32 domain_index;
>> +             struct platform_device *pd_pdev;
>> +             struct imx7_pgc_domain *domain;
>
> Reverse tree.
>

OK

>> +
>> +             ret = of_property_read_u32(np, "reg", &domain_index);
>> +             if (ret) {
>> +                     dev_err(dev, "Failed to read 'reg' property\n");
>> +                     of_node_put(np);
>> +                     return ret;
>> +             }
>> +
>> +             if (domain_index >= ARRAY_SIZE(imx7_pgc_domains)) {
>> +                     dev_warn(dev,
>> +                              "Domain index %d is out of bounds\n",
>> +                              domain_index);
>> +                     continue;
>> +             }
>> +
>> +             domain = &imx7_pgc_domains[domain_index];
>> +             domain->regmap = regmap;
>> +
>> +             pd_pdev = platform_device_alloc("imx7-pgc-domain",
>> +                                             domain_index);
>> +             if (!pd_pdev) {
>> +                     dev_err(dev, "Failed to allocate platform device\n");
>> +                     of_node_put(np);
>> +                     return -ENOMEM;
>> +             }
>> +
>> +             pd_pdev->dev.platform_data = domain;
>> +             pd_pdev->dev.parent = dev;
>> +             pd_pdev->dev.of_node = np;
>> +
>> +             ret = platform_device_add(pd_pdev);
>> +             if (ret) {
>> +                     platform_device_put(pd_pdev);
>> +                     of_node_put(np);
>> +                     return ret;
>> +             }
>> +     }
>> +
>> +     return 0;
>> +}
>> +
>> +static const struct of_device_id imx_gpcv2_dt_ids[] = {
>> +     { .compatible = "fsl,imx7d-gpc" },
>> +     { }
>> +};
>> +
>> +static struct platform_driver imx_gpc_driver = {
>> +     .driver = {
>> +             .name = "imx-gpcv2",
>> +             .of_match_table = imx_gpcv2_dt_ids,
>> +     },
>> +     .probe = imx_gpcv2_probe,
>> +};
>> +builtin_platform_driver(imx_gpc_driver)
>> diff --git a/include/dt-bindings/power/imx7-power.h b/include/dt-bindings/power/imx7-power.h
>> new file mode 100644
>> index 0000000..24dde62
>> --- /dev/null
>> +++ b/include/dt-bindings/power/imx7-power.h
>> @@ -0,0 +1,18 @@
>> +/*
>> + *  Copyright © 2017 Impinj
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + */
>> +
>> +#ifndef __DT_BINDINGS_ARM_IMX7_POWER_H__
>> +#define __DT_BINDINGS_ARM_IMX7_POWER_H__
>
> Drop 'ARM' from there.

OK.

>
> Shawn
>
>> +
>> +#define IMX7_POWER_DOMAIN_USB_HSIC_PHY       0
>> +#define IMX7_POWER_DOMAIN_USB_OTG2_PHY       1
>> +#define IMX7_POWER_DOMAIN_USB_OTG1_PHY       2
>> +#define IMX7_POWER_DOMAIN_PCIE_PHY   3
>> +#define IMX7_POWER_DOMAIN_MIPI_PHY   4
>> +
>> +#endif
>> --
>> 2.9.3
>>
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt b/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
new file mode 100644
index 0000000..02f45c6
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
@@ -0,0 +1,71 @@ 
+Freescale i.MX General Power Controller v2
+==========================================
+
+The i.MX7S/D General Power Control (GPC) block contains Power Gating
+Control (PGC) for various power domains.
+
+Required properties:
+
+- compatible: Should be "fsl,imx7d-gpc"
+
+- reg: should be register base and length as documented in the
+  datasheet
+
+- interrupts: Should contain GPC interrupt request 1
+
+Power domains contained within GPC node are generic power domain
+providers, documented in
+Documentation/devicetree/bindings/power/power_domain.txt, which are
+described as subnodes of the power gating controller 'pgc' node,
+which, in turn, is expected to contain the following:
+
+Required properties:
+
+- reg: Power domain index. Valid values are defined in
+  include/dt-bindings/power/imx7-power.h
+
+- #power-domain-cells: Should be 0
+
+Optional properties:
+
+- power-supply: Power supply used to power the domain
+
+Example:
+
+	gpc: gpc@303a0000 {
+		compatible = "fsl,imx7d-gpc";
+		reg = <0x303a0000 0x1000>;
+		interrupt-controller;
+		interrupts = <GIC_SPI 87 IRQ_TYPE_LEVEL_HIGH>;
+		#interrupt-cells = <3>;
+		interrupt-parent = <&intc>;
+
+		pgc {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			pgc_pcie_phy: power-domain@3 {
+				#power-domain-cells = <0>;
+
+				reg = <IMX7_POWER_DOMAIN_PCIE_PHY>;
+				power-supply = <&reg_1p0d>;
+			};
+		};
+	};
+
+
+Specifying power domain for IP modules
+======================================
+
+IP cores belonging to a power domain should contain a 'power-domains'
+property that is a phandle for PGC node representing the domain.
+
+Example of a device that is part of the PCIE_PHY power domain:
+
+	pcie: pcie@33800000 {
+	      reg = <0x33800000 0x4000>,
+	            <0x4ff00000 0x80000>;
+		/* ... */
+		power-domains = <&pgc_pcie_phy>;
+		/* ... */
+	};
diff --git a/drivers/soc/imx/Makefile b/drivers/soc/imx/Makefile
index 35861f5..7bcc933 100644
--- a/drivers/soc/imx/Makefile
+++ b/drivers/soc/imx/Makefile
@@ -1 +1 @@ 
-obj-y += gpc.o
+obj-y += gpc.o gpcv2.o
diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c
new file mode 100644
index 0000000..20f0515
--- /dev/null
+++ b/drivers/soc/imx/gpcv2.c
@@ -0,0 +1,397 @@ 
+/*
+ * Copyright 2017 Impinj, Inc
+ * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
+ *
+ * Based on the code of analogus driver:
+ *
+ * Copyright 2015-2017 Pengutronix, Lucas Stach <kernel@pengutronix.de>
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <dt-bindings/power/imx7-power.h>
+
+#define GPC_PGC_CPU_MAPPING	0xec
+#define USB_HSIC_PHY_A7_DOMAIN	BIT(6)
+#define USB_OTG2_PHY_A7_DOMAIN	BIT(5)
+#define USB_OTG1_PHY_A7_DOMAIN	BIT(4)
+#define PCIE_PHY_A7_DOMAIN	BIT(3)
+#define MIPI_PHY_A7_DOMAIN	BIT(2)
+
+#define GPC_PU_PGC_SW_PUP_REQ	0xf8
+#define GPC_PU_PGC_SW_PDN_REQ	0x104
+#define USB_HSIC_PHY_SW_Pxx_REQ	BIT(4)
+#define USB_OTG2_PHY_SW_Pxx_REQ	BIT(3)
+#define USB_OTG1_PHY_SW_Pxx_REQ	BIT(2)
+#define PCIE_PHY_SW_Pxx_REQ	BIT(1)
+#define MIPI_PHY_SW_Pxx_REQ	BIT(0)
+
+#define GPC_MAX_REGISTER	0x1000
+
+#define GPC_PGC_nCTRL_PCR	BIT(0)
+
+struct imx7_pgc_domain {
+	struct generic_pm_domain genpd;
+	struct regmap *regmap;
+	struct regulator *regulator;
+
+	unsigned int pgc_nctrl;
+
+	const struct {
+		u32 pxx;
+		u32 map;
+	} bits;
+
+	const int voltage;
+	struct device *dev;
+};
+
+static int imx7_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain *genpd,
+				      bool on)
+{
+	int ret = 0;
+	unsigned long deadline;
+	struct imx7_pgc_domain *domain = container_of(genpd,
+						      struct imx7_pgc_domain,
+						      genpd);
+	unsigned int offset = (on) ?
+		GPC_PU_PGC_SW_PUP_REQ : GPC_PU_PGC_SW_PDN_REQ;
+
+	const bool has_regulator = !IS_ERR(domain->regulator);
+	const bool enable_power_control = domain->pgc_nctrl && !on;
+
+	regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
+			   domain->bits.map, domain->bits.map);
+	if (has_regulator && on) {
+		ret = regulator_enable(domain->regulator);
+		if (ret) {
+			dev_err(domain->dev, "failed to enable regulator\n");
+			goto unmap;
+		}
+	}
+
+	if (enable_power_control)
+		regmap_update_bits(domain->regmap, domain->pgc_nctrl,
+				   GPC_PGC_nCTRL_PCR, GPC_PGC_nCTRL_PCR);
+
+
+	regmap_update_bits(domain->regmap, offset,
+			   domain->bits.pxx, domain->bits.pxx);
+	/*
+	 * As per "5.5.9.4 Example Code 4" in IMX7DRM.pdf wait
+	 * for PUP_REQ/PDN_REQ bit to be cleared
+	 */
+	deadline = jiffies + msecs_to_jiffies(1);
+	while (true) {
+		u32 pxx_req;
+
+		regmap_read(domain->regmap, offset, &pxx_req);
+
+		if (!(pxx_req & domain->bits.pxx))
+			break;
+
+		if (time_after(jiffies, deadline)) {
+			dev_err(domain->dev, "falied to command PGC\n");
+			ret = -ETIMEDOUT;
+			/*
+			 * If we were in a process of enabling a
+			 * domain and failed we might as well disable
+			 * the regulator we just enabled. And if it
+			 * was the opposite situation and we failed to
+			 * power down -- keep the regulator on
+			 */
+			on  = !on;
+			break;
+		}
+
+		cpu_relax();
+	}
+
+	if (enable_power_control)
+		regmap_update_bits(domain->regmap, domain->pgc_nctrl,
+				   GPC_PGC_nCTRL_PCR, 0);
+
+	if (has_regulator && !on) {
+		int err;
+
+		err = regulator_disable(domain->regulator);
+		if (err)
+			dev_err(domain->dev,
+				"failed to disable regulator: %d\n", ret);
+		/*
+		 * Preserve earlier error code
+		 */
+		ret = ret ?: err;
+	}
+unmap:
+	regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
+			   domain->bits.map, 0);
+	return ret;
+}
+
+static int imx7_gpc_pu_pgc_sw_pup_req(struct generic_pm_domain *genpd)
+{
+	return imx7_gpc_pu_pgc_sw_pxx_req(genpd, true);
+}
+
+static int imx7_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain *genpd)
+{
+	return imx7_gpc_pu_pgc_sw_pxx_req(genpd, false);
+}
+
+static struct imx7_pgc_domain imx7_pgc_domains[] = {
+	[IMX7_POWER_DOMAIN_USB_HSIC_PHY] = {
+		.genpd = {
+			.name      = "usb-hsic-phy",
+			.power_on  = imx7_gpc_pu_pgc_sw_pup_req,
+			.power_off = imx7_gpc_pu_pgc_sw_pdn_req,
+		},
+		.bits  = {
+			.pxx = USB_HSIC_PHY_SW_Pxx_REQ,
+			.map = USB_HSIC_PHY_A7_DOMAIN,
+		},
+		.voltage   = 1200000,
+		.pgc_nctrl = 0x0d00,
+	},
+
+	[IMX7_POWER_DOMAIN_USB_OTG2_PHY] = {
+		.genpd = {
+			.name      = "usb-otg2-phy",
+			.power_on  = imx7_gpc_pu_pgc_sw_pup_req,
+			.power_off = imx7_gpc_pu_pgc_sw_pdn_req,
+		},
+		.bits  = {
+			.pxx = USB_OTG2_PHY_SW_Pxx_REQ,
+			.map = USB_OTG2_PHY_A7_DOMAIN,
+		},
+	},
+
+	[IMX7_POWER_DOMAIN_USB_OTG1_PHY] = {
+		.genpd = {
+			.name      = "usb-otg1-phy",
+			.power_on  = imx7_gpc_pu_pgc_sw_pup_req,
+			.power_off = imx7_gpc_pu_pgc_sw_pdn_req,
+		},
+		.bits  = {
+			.pxx = USB_OTG1_PHY_SW_Pxx_REQ,
+			.map = USB_OTG1_PHY_A7_DOMAIN,
+		},
+	},
+
+	[IMX7_POWER_DOMAIN_PCIE_PHY] = {
+		.genpd = {
+			.name      = "pcie-phy",
+			.power_on  = imx7_gpc_pu_pgc_sw_pup_req,
+			.power_off = imx7_gpc_pu_pgc_sw_pdn_req,
+		},
+		.bits  = {
+			.pxx = PCIE_PHY_SW_Pxx_REQ,
+			.map = PCIE_PHY_A7_DOMAIN,
+		},
+		.voltage   = 1000000,
+		.pgc_nctrl = 0x0c40,
+	},
+
+	[IMX7_POWER_DOMAIN_MIPI_PHY] = {
+		.genpd = {
+			.name      = "mipi-phy",
+			.power_on  = imx7_gpc_pu_pgc_sw_pup_req,
+			.power_off = imx7_gpc_pu_pgc_sw_pdn_req,
+		},
+		.bits  = {
+			.pxx = MIPI_PHY_SW_Pxx_REQ,
+			.map = MIPI_PHY_A7_DOMAIN,
+		},
+		.voltage   = 1000000,
+		.pgc_nctrl = 0x0c00,
+	},
+};
+
+static int imx7_pgc_domain_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct imx7_pgc_domain *domain = pdev->dev.platform_data;
+
+	if (!IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS))
+		return 0;
+
+	domain->dev = &pdev->dev;
+
+	ret = pm_genpd_init(&domain->genpd, NULL, true);
+	if (ret) {
+		dev_err(domain->dev, "Failed to init power domain\n");
+		return ret;
+	}
+
+	domain->regulator = devm_regulator_get_optional(domain->dev, "power");
+	if (IS_ERR(domain->regulator)  &&
+	    PTR_ERR(domain->regulator) != -ENODEV) {
+		dev_err(domain->dev, "Failed to get domain's regulator\n");
+		return PTR_ERR(domain->regulator);
+	}
+
+	if (!IS_ERR(domain->regulator)) {
+		WARN_ON(!domain->voltage);
+		regulator_set_voltage(domain->regulator,
+				      domain->voltage, domain->voltage);
+	}
+
+	ret = of_genpd_add_provider_simple(domain->dev->of_node,
+					   &domain->genpd);
+	if (ret) {
+		dev_err(domain->dev, "Failed to add genpd provider\n");
+		pm_genpd_remove(&domain->genpd);
+	}
+
+	return ret;
+}
+
+static int imx7_pgc_domain_remove(struct platform_device *pdev)
+{
+	struct imx7_pgc_domain *domain = pdev->dev.platform_data;
+
+	if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
+		of_genpd_del_provider(domain->dev->of_node);
+		pm_genpd_remove(&domain->genpd);
+	}
+
+	return 0;
+}
+
+static const struct platform_device_id imx7_pgc_domain_id[] = {
+	{ "imx7-pgc-domain", },
+	{ },
+};
+
+static struct platform_driver imx7_pgc_domain_driver = {
+	.driver = {
+		.name = "imx7-pgc",
+	},
+	.probe    = imx7_pgc_domain_probe,
+	.remove   = imx7_pgc_domain_remove,
+	.id_table = imx7_pgc_domain_id,
+};
+builtin_platform_driver(imx7_pgc_domain_driver)
+
+static bool imx_gpcv2_readable_reg(struct device *dev, unsigned int reg)
+{
+	return reg % 4 == 0 &&
+	       reg <= GPC_MAX_REGISTER;
+}
+
+static bool imx_gpcv2_volatile_reg(struct device *dev, unsigned int reg)
+{
+	return reg == GPC_PU_PGC_SW_PUP_REQ ||
+	       reg == GPC_PU_PGC_SW_PDN_REQ;
+}
+
+static int imx_gpcv2_probe(struct platform_device *pdev)
+{
+	int ret;
+	void __iomem *base;
+	struct resource *res;
+	struct regmap *regmap;
+	struct device *dev = &pdev->dev;
+	struct device_node *pgc_np, *np;
+
+	static const struct regmap_config regmap_config = {
+		.cache_type	= REGCACHE_FLAT,
+		.reg_bits	= 32,
+		.val_bits	= 32,
+		.reg_stride	= 4,
+
+		.readable_reg	= imx_gpcv2_readable_reg,
+		.volatile_reg	= imx_gpcv2_volatile_reg,
+
+		.max_register	= GPC_MAX_REGISTER,
+	};
+
+	pgc_np = of_get_child_by_name(dev->of_node, "pgc");
+	if (!pgc_np) {
+		dev_err(dev, "No power domains specified in DT\n");
+		return -EINVAL;
+	}
+
+	res  = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	regmap = devm_regmap_init_mmio(dev, base, &regmap_config);
+	if (IS_ERR(regmap)) {
+		ret = PTR_ERR(regmap);
+		dev_err(dev, "failed to init regmap\n");
+		return ret;
+	}
+
+	for_each_child_of_node(pgc_np, np) {
+		u32 domain_index;
+		struct platform_device *pd_pdev;
+		struct imx7_pgc_domain *domain;
+
+		ret = of_property_read_u32(np, "reg", &domain_index);
+		if (ret) {
+			dev_err(dev, "Failed to read 'reg' property\n");
+			of_node_put(np);
+			return ret;
+		}
+
+		if (domain_index >= ARRAY_SIZE(imx7_pgc_domains)) {
+			dev_warn(dev,
+				 "Domain index %d is out of bounds\n",
+				 domain_index);
+			continue;
+		}
+
+		domain = &imx7_pgc_domains[domain_index];
+		domain->regmap = regmap;
+
+		pd_pdev = platform_device_alloc("imx7-pgc-domain",
+						domain_index);
+		if (!pd_pdev) {
+			dev_err(dev, "Failed to allocate platform device\n");
+			of_node_put(np);
+			return -ENOMEM;
+		}
+
+		pd_pdev->dev.platform_data = domain;
+		pd_pdev->dev.parent = dev;
+		pd_pdev->dev.of_node = np;
+
+		ret = platform_device_add(pd_pdev);
+		if (ret) {
+			platform_device_put(pd_pdev);
+			of_node_put(np);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static const struct of_device_id imx_gpcv2_dt_ids[] = {
+	{ .compatible = "fsl,imx7d-gpc" },
+	{ }
+};
+
+static struct platform_driver imx_gpc_driver = {
+	.driver = {
+		.name = "imx-gpcv2",
+		.of_match_table = imx_gpcv2_dt_ids,
+	},
+	.probe = imx_gpcv2_probe,
+};
+builtin_platform_driver(imx_gpc_driver)
diff --git a/include/dt-bindings/power/imx7-power.h b/include/dt-bindings/power/imx7-power.h
new file mode 100644
index 0000000..24dde62
--- /dev/null
+++ b/include/dt-bindings/power/imx7-power.h
@@ -0,0 +1,18 @@ 
+/*
+ *  Copyright © 2017 Impinj
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __DT_BINDINGS_ARM_IMX7_POWER_H__
+#define __DT_BINDINGS_ARM_IMX7_POWER_H__
+
+#define IMX7_POWER_DOMAIN_USB_HSIC_PHY	0
+#define IMX7_POWER_DOMAIN_USB_OTG2_PHY	1
+#define IMX7_POWER_DOMAIN_USB_OTG1_PHY	2
+#define IMX7_POWER_DOMAIN_PCIE_PHY	3
+#define IMX7_POWER_DOMAIN_MIPI_PHY	4
+
+#endif