diff mbox

can: rcar_canfd: Add Renesas R-Car CAN FD driver

Message ID 1456824849-7987-1-git-send-email-ramesh.shanmugasundaram@bp.renesas.com (mailing list archive)
State Superseded
Delegated to: Geert Uytterhoeven
Headers show

Commit Message

Ramesh Shanmugasundaram March 1, 2016, 9:34 a.m. UTC
This patch adds support for the CAN FD controller found in Renesas R-Car
SoCs. The controller operates in CAN FD mode by default. Two test modes
are available and can be enabled by the "rcar_canfd.testmode" module
parameter. Refer to Documentation/kernel-parameters.txt.

CAN FD mode supports both Classical CAN & CAN FD frame formats. The
controller supports ISO 11898-1:2015 CAN FD format only.

This controller supports two channels and the driver can enable either
or both of the channels.

Driver uses Rx FIFOs (one per channel) for reception & Common FIFOs (one
per channel) for transmission. Rx filter rules are configured to the
minimum (one per channel) and it accepts Standard, Extended, Data &
Remote Frame combinations.

Note: There are few documentation errors in R-Car Gen3 Hardware User
Manual v0.5E with respect to CAN FD controller. They are listed below:

1. CAN FD interrupt numbers 29 & 30 are listed as per channel
interrupts. However, they are common to both channels (i.e.) they are
global and channel interrupts respectively.

2. CANFD clock is derived from PLL1. This is not documented.

3. CANFD clock is further divided by (1/2) within the CAN FD controller.
This is not documented.

4. The minimum value of NTSEG1 in RSCFDnCFDCmNCFG register is 2 Tq. It
is mentioned 4 Tq in the manual.

5. The maximum number of message RAM area the controller can use is 3584
bytes. It is mentioned 10752 bytes in the manual.

Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
---
Hi All,

   This work is based on linux-can-next (tag:linux-can-next-for-4.6-20160226) with
   the following patch applied on top

   [PATCH] can: rcar_can: Add r8a7795 support

   Pinctrl & Clock related to the controller are already submitted as below:

   https://lkml.org/lkml/2016/2/25/546
   https://lkml.org/lkml/2016/2/26/452
   http://www.spinics.net/lists/arm-kernel/msg487238.html

   DT submission will be done separately based on linux-next

Thanks,
Ramesh
---
 .../devicetree/bindings/net/can/rcar_canfd.txt     |   86 +
 Documentation/kernel-parameters.txt                |    8 +
 drivers/net/can/Kconfig                            |   10 +
 drivers/net/can/Makefile                           |    1 +
 drivers/net/can/rcar_canfd.c                       | 1905 ++++++++++++++++++++
 5 files changed, 2010 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/net/can/rcar_canfd.txt
 create mode 100644 drivers/net/can/rcar_canfd.c

Comments

Marc Kleine-Budde March 1, 2016, 8:41 p.m. UTC | #1
On 03/01/2016 10:34 AM, Ramesh Shanmugasundaram wrote:
> This patch adds support for the CAN FD controller found in Renesas R-Car
> SoCs. The controller operates in CAN FD mode by default. Two test modes
> are available and can be enabled by the "rcar_canfd.testmode" module
> parameter. Refer to Documentation/kernel-parameters.txt.

Is the channel loopback mode configurable per channel? If so, please
remove the module parameter and make use of CAN_CTRLMODE_LOOPBACK to
configure it.

> CAN FD mode supports both Classical CAN & CAN FD frame formats. The
> controller supports ISO 11898-1:2015 CAN FD format only.
> 
> This controller supports two channels and the driver can enable either
> or both of the channels.
> 
> Driver uses Rx FIFOs (one per channel) for reception & Common FIFOs (one
> per channel) for transmission. Rx filter rules are configured to the
> minimum (one per channel) and it accepts Standard, Extended, Data &
> Remote Frame combinations.

I see no locking for the tx-path.

> Note: There are few documentation errors in R-Car Gen3 Hardware User
> Manual v0.5E with respect to CAN FD controller. They are listed below:
> 
> 1. CAN FD interrupt numbers 29 & 30 are listed as per channel
> interrupts. However, they are common to both channels (i.e.) they are
> global and channel interrupts respectively.
> 
> 2. CANFD clock is derived from PLL1. This is not documented.
> 
> 3. CANFD clock is further divided by (1/2) within the CAN FD controller.
> This is not documented.
> 
> 4. The minimum value of NTSEG1 in RSCFDnCFDCmNCFG register is 2 Tq. It
> is mentioned 4 Tq in the manual.
> 
> 5. The maximum number of message RAM area the controller can use is 3584
> bytes. It is mentioned 10752 bytes in the manual.
> 
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>

Marc
Oliver Hartkopp March 1, 2016, 9:07 p.m. UTC | #2
On 03/01/2016 10:34 AM, Ramesh Shanmugasundaram wrote:
> This patch adds support for the CAN FD controller found in Renesas R-Car
> SoCs. The controller operates in CAN FD mode by default. Two test modes
> are available and can be enabled by the "rcar_canfd.testmode" module
> parameter. Refer to Documentation/kernel-parameters.txt.

(..)

> +#ifdef CONFIG_DEBUG_FS
> +#include <linux/debugfs.h>
> +
> +static int rcar_canfd_showregs(struct seq_file *s, void *data)
> +{
> +	struct rcar_canfd_channel *priv = s->private;
> +	u32 ch = priv->channel;
> +	u32 rf = ch + RCANFD_RFFIFO_IDX;
> +	u32 cf = RCANFD_CFFIFO_IDX;
> +	u32 val, offset, i;
> +
> +	if (testmode)
> +		seq_printf(s, "RCANFD : testmode = %d\n", testmode);
> +	seq_printf(s, "RCANFD register dump: channel %u\n", ch);
> +	seq_printf(s, "%-40s: %x\n", "g: cfg",
> +		   rcar_canfd_read(priv, RCANFD_GCFG));

Why do you think you would need this kind of register dumps in debugfs?

This could be interesting for development purposes - but in production drivers
this is pretty unusual and needless.

I would sugest to remove either the testmode (already suggested by Marc) and
this register dump stuff.

Regards,
Oliver
Ramesh Shanmugasundaram March 2, 2016, 8:41 a.m. UTC | #3
Hi Marc,

Thanks for the review.

> On 03/01/2016 10:34 AM, Ramesh Shanmugasundaram wrote:

> > This patch adds support for the CAN FD controller found in Renesas

> > R-Car SoCs. The controller operates in CAN FD mode by default. Two

> > test modes are available and can be enabled by the

> > "rcar_canfd.testmode" module parameter. Refer to Documentation/kernel-

> parameters.txt.

> 

> Is the channel loopback mode configurable per channel? If so, please

> remove the module parameter and make use of CAN_CTRLMODE_LOOPBACK to

> configure it.


The loopback setting is not truly a per channel attribute. It requires touching Rx rules which can be done only when the controller's global state is reset (during probe). CAN_CTRLMODE_LOOPBACK config option is possible only through .ndo_open of that channel but the global controller state needs to be operational by this time. As it is a global attribute & for the above reason, I choose the module option.

> 

> > CAN FD mode supports both Classical CAN & CAN FD frame formats. The

> > controller supports ISO 11898-1:2015 CAN FD format only.

> >

> > This controller supports two channels and the driver can enable either

> > or both of the channels.

> >

> > Driver uses Rx FIFOs (one per channel) for reception & Common FIFOs

> > (one per channel) for transmission. Rx filter rules are configured to

> > the minimum (one per channel) and it accepts Standard, Extended, Data

> > & Remote Frame combinations.

> 

> I see no locking for the tx-path.

 
I am not sure why locking is needed in tx-path? 
However, looking at it again, I should move the incrementing of head after the "sts" handing to be apt. What do you think?

Thanks,
Ramesh
Ramesh Shanmugasundaram March 2, 2016, 8:45 a.m. UTC | #4
Hi Oliver,

Thanks for the review.

> On 03/01/2016 10:34 AM, Ramesh Shanmugasundaram wrote:
> > This patch adds support for the CAN FD controller found in Renesas
> > R-Car SoCs. The controller operates in CAN FD mode by default. Two
> > test modes are available and can be enabled by the
> > "rcar_canfd.testmode" module parameter. Refer to Documentation/kernel-
> parameters.txt.
> 
> (..)
> 
> > +#ifdef CONFIG_DEBUG_FS
> > +#include <linux/debugfs.h>
> > +
> > +static int rcar_canfd_showregs(struct seq_file *s, void *data) {
> > +	struct rcar_canfd_channel *priv = s->private;
> > +	u32 ch = priv->channel;
> > +	u32 rf = ch + RCANFD_RFFIFO_IDX;
> > +	u32 cf = RCANFD_CFFIFO_IDX;
> > +	u32 val, offset, i;
> > +
> > +	if (testmode)
> > +		seq_printf(s, "RCANFD : testmode = %d\n", testmode);
> > +	seq_printf(s, "RCANFD register dump: channel %u\n", ch);
> > +	seq_printf(s, "%-40s: %x\n", "g: cfg",
> > +		   rcar_canfd_read(priv, RCANFD_GCFG));
> 
> Why do you think you would need this kind of register dumps in debugfs?
> 
> This could be interesting for development purposes - but in production
> drivers this is pretty unusual and needless.

I thought it would be useful when we add more features to the driver (e.g. Gateway mode).
 
> 
> I would sugest to remove either the testmode (already suggested by Marc)
> and this register dump stuff.

OK. I'll remove both.

Thanks,
Ramesh
Marc Kleine-Budde March 2, 2016, 9:20 a.m. UTC | #5
On 03/02/2016 09:41 AM, Ramesh Shanmugasundaram wrote:
>> Is the channel loopback mode configurable per channel? If so, please
>> remove the module parameter and make use of CAN_CTRLMODE_LOOPBACK to
>> configure it.
> 
> The loopback setting is not truly a per channel attribute. It
> requires touching Rx rules which can be done only when the
> controller's global state is reset (during probe).
> CAN_CTRLMODE_LOOPBACK config option is possible only through
> .ndo_open of that channel but the global controller state needs to be
> operational by this time. As it is a global attribute & for the above
> reason, I choose the module option.

I see, ok then.

>>> CAN FD mode supports both Classical CAN & CAN FD frame formats. The
>>> controller supports ISO 11898-1:2015 CAN FD format only.
>>>
>>> This controller supports two channels and the driver can enable either
>>> or both of the channels.
>>>
>>> Driver uses Rx FIFOs (one per channel) for reception & Common FIFOs
>>> (one per channel) for transmission. Rx filter rules are configured to
>>> the minimum (one per channel) and it accepts Standard, Extended, Data
>>> & Remote Frame combinations.
>>
>> I see no locking for the tx-path.
>  
> I am not sure why locking is needed in tx-path? 

If the tx-path is shared between both channels you need locking as the
networking subsystem may send one frame to each controller at the same time.

> However, looking at it again, I should move the incrementing of head
> after the "sts" handing to be apt. What do you think?

With one producer (one SW instance) and one consumer (the HW) you can
write lockless code (if the HW allows it), but with two producers it's
not possible.

Marc
Ramesh Shanmugasundaram March 2, 2016, 10:08 a.m. UTC | #6
Hi Marc,

> On 03/02/2016 09:41 AM, Ramesh Shanmugasundaram wrote:

> >> Is the channel loopback mode configurable per channel? If so, please

> >> remove the module parameter and make use of CAN_CTRLMODE_LOOPBACK to

> >> configure it.

> >

> > The loopback setting is not truly a per channel attribute. It requires

> > touching Rx rules which can be done only when the controller's global

> > state is reset (during probe).

> > CAN_CTRLMODE_LOOPBACK config option is possible only through .ndo_open

> > of that channel but the global controller state needs to be

> > operational by this time. As it is a global attribute & for the above

> > reason, I choose the module option.

> 

> I see, ok then.

> 

> >>> CAN FD mode supports both Classical CAN & CAN FD frame formats. The

> >>> controller supports ISO 11898-1:2015 CAN FD format only.

> >>>

> >>> This controller supports two channels and the driver can enable

> >>> either or both of the channels.

> >>>

> >>> Driver uses Rx FIFOs (one per channel) for reception & Common FIFOs

> >>> (one per channel) for transmission. Rx filter rules are configured

> >>> to the minimum (one per channel) and it accepts Standard, Extended,

> >>> Data & Remote Frame combinations.

> >>

> >> I see no locking for the tx-path.

> >

> > I am not sure why locking is needed in tx-path?

> 

> If the tx-path is shared between both channels you need locking as the

> networking subsystem may send one frame to each controller at the same

> time.


Yes. Tx completion interrupt is shared by both channels but the Tx FIFO, echo skbs, head, tail are maintained on a per channel basis. 
Yes, net subsystem can send one frame to each channel at the same time and the tx completion interrupt handler will traverse each channel & update per channel context accordingly.

> > However, looking at it again, I should move the incrementing of head

> > after the "sts" handing to be apt. What do you think?

> 

> With one producer (one SW instance) and one consumer (the HW) you can

> write lockless code (if the HW allows it), but with two producers it's not

> possible.


For a channel represented as netdev, there is still one producer (one SW instance) isn't it? net acquires lock before calling xmit. The consumer is tx completion interrupt handler which updates per channel attributes only.

Sorry if I am annoying. I have tested this with two channels transmitting & receiving at the same time and it works fine. If I am missing lock, I would like to understand it thoroughly before making the change.

Thanks for the help,
Ramesh.
Marc Kleine-Budde March 2, 2016, 10:21 a.m. UTC | #7
On 03/02/2016 11:08 AM, Ramesh Shanmugasundaram wrote:
>>>> I see no locking for the tx-path.
>>>
>>> I am not sure why locking is needed in tx-path?
>>
>> If the tx-path is shared between both channels you need locking as the
>> networking subsystem may send one frame to each controller at the same
>> time.
> 
> Yes. Tx completion interrupt is shared by both channels but the Tx
> FIFO, echo skbs, head, tail are maintained on a per channel basis. 
> Yes, net subsystem can send one frame to each channel at the same
> time and the tx completion interrupt handler will traverse each
> channel & update per channel context accordingly.

Ok. Which instruction starts the transmit? Please add a comment to the
code. You stop the tx_queue after this, so your code is racy, as the
interrupt might happen in between.

>>> However, looking at it again, I should move the incrementing of head
>>> after the "sts" handing to be apt. What do you think?
>>
>> With one producer (one SW instance) and one consumer (the HW) you can
>> write lockless code (if the HW allows it), but with two producers it's not
>> possible.
> 
> For a channel represented as netdev, there is still one producer (one
> SW instance) isn't it? net acquires lock before calling xmit. The
> consumer is tx completion interrupt handler which updates per channel
> attributes only.

Ok - I haven't looked at the code in depth yet. Now it's clear, that
just the tx interrupt is shared.

> Sorry if I am annoying. I have tested this with two channels
> transmitting & receiving at the same time and it works fine. If I am
> missing lock, I would like to understand it thoroughly before making
> the change.

Marc
Ramesh Shanmugasundaram March 3, 2016, 1:48 p.m. UTC | #8
Hi Marc,

Sorry for the late response.

> On 03/02/2016 11:08 AM, Ramesh Shanmugasundaram wrote:

> >>>> I see no locking for the tx-path.

> >>>

> >>> I am not sure why locking is needed in tx-path?

> >>

> >> If the tx-path is shared between both channels you need locking as

> >> the networking subsystem may send one frame to each controller at the

> >> same time.

> >

> > Yes. Tx completion interrupt is shared by both channels but the Tx

> > FIFO, echo skbs, head, tail are maintained on a per channel basis.

> > Yes, net subsystem can send one frame to each channel at the same time

> > and the tx completion interrupt handler will traverse each channel &

> > update per channel context accordingly.

> 

> Ok. Which instruction starts the transmit? Please add a comment to the

> code.


Please see

---<snip>---

+	/* Start Tx: Write 0xff to CFPC to increment the CPU-side
+	 * pointer for the Common FIFO
+	 */
+	rcar_canfd_write(priv, RCANFD_CFPCTR(ch, RCANFD_CFFIFO_IDX), 0xff);

---<snip>---

> You stop the tx_queue after this, so your code is racy, as the

> interrupt might happen in between.


It is a very good point. Thank you. 
I managed to reproduce this issue once with 50Kbps rate and ignoring -ENOBUFS in user space. It also exposed another subtle issue in the echo skb management where the tx_done loop pushes the skb before the actual ACK for that index happens. Fixed both issues.
As you mentioned, I have introduced a lock to protect this critical section. I'll send the updates in the next v2 patch.

Thanks,
Ramesh
Ramesh Shanmugasundaram April 28, 2016, 12:23 p.m. UTC | #9
Hi All,

   This patch is based on commit "885cc17abad6" of can-next/testing branch

Changes since v4:
	* Rebased to latest can-next/testing branch
	* Addressed Marc K review comments on v2 patch
	* Use clk_get_rate() to find ext clock availability. Refer thread
	(https://lkml.org/lkml/2016/4/8/203)

Changes since v3:
	* Split v3 patch into two (Marc K)
	  (1) Introduce rcar_canfd.c driver in drivers/net/can/rcar dir
	  (2) Move rcar_can.c driver to new drivers/net/can/rcar dir
	* Added Acked-by Rob H for the bindings
	* Added comments on CAN FD only mode in driver & Kconfig (Oliver H)

Changes since v2:
	* Rebased to latest tag (linux-can-next-for-4.6-20160310)
	* Cleaned up leftover debugfs code (Thanks Oliver H)
	* Revised devicetree documentation text (as suggested by Rob H)
	  (https://www.mail-archive.com/linux-renesas-soc@vger.kernel.org/msg01597.html)
	* Used new can subsystem api to set static configuration & removed check in rcar_canfd_start (as suggested by Oliver H)
	  (Refer: http://comments.gmane.org/gmane.linux.can/9126 &
	   https://www.mail-archive.com/linux-renesas-soc@vger.kernel.org/msg01867.html)
	* Clubbed Renesas controller drivers to driver/net/can/rcar dir (as suggested by Oliver H)
	* Updated commit message

Changes since v1:
	* Removed testmodes & debugfs code (suggested by Oliver H)
	* Fixed tx path race issue by introducing lock (suggested by Marc K)
	* Removed __maybe_unused attribute of rcar_canfd_of_table

Ramesh Shanmugasundaram (2):
  can: rcar_canfd: Add Renesas R-Car CAN FD driver
  can: rcar_can: Move Renesas CAN driver to rcar dir

 .../devicetree/bindings/net/can/rcar_canfd.txt     |   89 ++
 drivers/net/can/Kconfig                            |   11 +-
 drivers/net/can/Makefile                           |    2 +-
 drivers/net/can/rcar/Kconfig                       |   21 +
 drivers/net/can/rcar/Makefile                      |    6 +
 drivers/net/can/{ => rcar}/rcar_can.c              |    0
 drivers/net/can/rcar/rcar_canfd.c                  | 1624 ++++++++++++++++++++
 7 files changed, 1742 insertions(+), 11 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/net/can/rcar_canfd.txt
 create mode 100644 drivers/net/can/rcar/Kconfig
 create mode 100644 drivers/net/can/rcar/Makefile
 rename drivers/net/can/{ => rcar}/rcar_can.c (100%)
 create mode 100644 drivers/net/can/rcar/rcar_canfd.c
Chris Paterson May 16, 2016, 3:52 p.m. UTC | #10
Hello Marc.

This patch series has been waiting for a response for a while now and we are keen to see it included upstream.

Are there any blocking points to it being accepted?


Kind regards, Chris


> -----Original Message-----
> From: Ramesh Shanmugasundaram
> [mailto:ramesh.shanmugasundaram@bp.renesas.com]
> Sent: 28 April 2016 13:23
> To: mkl@pengutronix.de; wg@grandegger.com; socketcan@hartkopp.net;
> robh+dt@kernel.org; pawel.moll@arm.com; mark.rutland@arm.com;
> ijc+devicetree@hellion.org.uk; galak@codeaurora.org
> Cc: linux-renesas-soc@vger.kernel.org; devicetree@vger.kernel.org; linux-
> can@vger.kernel.org; netdev@vger.kernel.org; Chris Paterson
> <Chris.Paterson2@renesas.com>; Ramesh Shanmugasundaram
> <ramesh.shanmugasundaram@bp.renesas.com>
> Subject: [PATCH v5 0/2] Add CAN FD driver support to r8a7795 SoC
> 
> Hi All,
> 
>    This patch is based on commit "885cc17abad6" of can-next/testing branch
> 
> Changes since v4:
> 	* Rebased to latest can-next/testing branch
> 	* Addressed Marc K review comments on v2 patch
> 	* Use clk_get_rate() to find ext clock availability. Refer thread
> 	(https://lkml.org/lkml/2016/4/8/203)
> 
> Changes since v3:
> 	* Split v3 patch into two (Marc K)
> 	  (1) Introduce rcar_canfd.c driver in drivers/net/can/rcar dir
> 	  (2) Move rcar_can.c driver to new drivers/net/can/rcar dir
> 	* Added Acked-by Rob H for the bindings
> 	* Added comments on CAN FD only mode in driver & Kconfig (Oliver
> H)
> 
> Changes since v2:
> 	* Rebased to latest tag (linux-can-next-for-4.6-20160310)
> 	* Cleaned up leftover debugfs code (Thanks Oliver H)
> 	* Revised devicetree documentation text (as suggested by Rob H)
> 	  (https://www.mail-archive.com/linux-renesas-
> soc@vger.kernel.org/msg01597.html)
> 	* Used new can subsystem api to set static configuration & removed
> check in rcar_canfd_start (as suggested by Oliver H)
> 	  (Refer: http://comments.gmane.org/gmane.linux.can/9126 &
> 	   https://www.mail-archive.com/linux-renesas-
> soc@vger.kernel.org/msg01867.html)
> 	* Clubbed Renesas controller drivers to driver/net/can/rcar dir (as
> suggested by Oliver H)
> 	* Updated commit message
> 
> Changes since v1:
> 	* Removed testmodes & debugfs code (suggested by Oliver H)
> 	* Fixed tx path race issue by introducing lock (suggested by Marc K)
> 	* Removed __maybe_unused attribute of rcar_canfd_of_table
> 
> Ramesh Shanmugasundaram (2):
>   can: rcar_canfd: Add Renesas R-Car CAN FD driver
>   can: rcar_can: Move Renesas CAN driver to rcar dir
> 
>  .../devicetree/bindings/net/can/rcar_canfd.txt     |   89 ++
>  drivers/net/can/Kconfig                            |   11 +-
>  drivers/net/can/Makefile                           |    2 +-
>  drivers/net/can/rcar/Kconfig                       |   21 +
>  drivers/net/can/rcar/Makefile                      |    6 +
>  drivers/net/can/{ => rcar}/rcar_can.c              |    0
>  drivers/net/can/rcar/rcar_canfd.c                  | 1624 ++++++++++++++++++++
>  7 files changed, 1742 insertions(+), 11 deletions(-)  create mode 100644
> Documentation/devicetree/bindings/net/can/rcar_canfd.txt
>  create mode 100644 drivers/net/can/rcar/Kconfig  create mode 100644
> drivers/net/can/rcar/Makefile  rename drivers/net/can/{ => rcar}/rcar_can.c
> (100%)  create mode 100644 drivers/net/can/rcar/rcar_canfd.c
> 
> --
> 1.9.1
Ulrich Hecht June 2, 2016, 4:01 p.m. UTC | #11
Thank you for your patch.

On Thu, Jun 2, 2016 at 11:45 AM, Ramesh Shanmugasundaram
<ramesh.shanmugasundaram@bp.renesas.com> wrote:
[...]
> diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
> new file mode 100644
> index 0000000..e198732
> --- /dev/null
> +++ b/drivers/net/can/rcar/rcar_canfd.c
> @@ -0,0 +1,1624 @@
> +/* Renesas R-Car CAN FD device driver
> + *
> + * Copyright (C) 2015 Renesas Electronics Corp.
> + *
> + * This program is free software; you can redistribute  it and/or modify it
> + * under  the terms of  the GNU General  Public License as published by the
> + * Free Software Foundation;  either version 2 of the  License, or (at your
> + * option) any later version.
> + */
> +
> +/* The R-Car CAN FD controller can operate in either one of the below two modes
> + *  - CAN FD only mode
> + *  - Classical CAN (CAN 2.0) only mode
> + *
> + * This driver puts the controller in CAN FD only mode by default. In this
> + * mode, the controller acts as a CAN FD node that can also interoperate with
> + * CAN 2.0 nodes.
> + *
> + * As of now, this driver does not support the Classical CAN (CAN 2.0) mode,
> + * which is handled by a different register map compared to CAN FD only mode.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/moduleparam.h>
> +#include <linux/kernel.h>
> +#include <linux/types.h>
> +#include <linux/interrupt.h>
> +#include <linux/errno.h>
> +#include <linux/netdevice.h>
> +#include <linux/platform_device.h>
> +#include <linux/can/led.h>
> +#include <linux/can/dev.h>
> +#include <linux/clk.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/bitmap.h>
> +#include <linux/bitops.h>
> +#include <linux/iopoll.h>
> +
> +#define RCANFD_DRV_NAME                        "rcar_canfd"
> +
> +#define RCANFD_FIFO_DEPTH              8       /* Tx FIFO depth */
> +#define RCANFD_NAPI_WEIGHT             8       /* Rx poll quota */
> +
> +#define RCANFD_NUM_CHANNELS            2       /* Two channels max */
> +#define RCANFD_CHANNELS_MASK           BIT((RCANFD_NUM_CHANNELS) - 1)
> +
> +/* Rx FIFO is a global resource of the controller. There are 8 such FIFOs
> + * available. Each channel gets a dedicated Rx FIFO (i.e.) the channel
> + * number is added to RFFIFO index.
> + */
> +#define RCANFD_RFFIFO_IDX              0
> +
> +/* Tx/Rx or Common FIFO is a per channel resource. Each channel has 3 Common
> + * FIFOs dedicated to them. Use the first (index 0) FIFO out of the 3 for Tx.
> + */
> +#define RCANFD_CFFIFO_IDX              0
> +
> +/* Global register bits */
> +#define RCANFD_GINTF_CANFD             BIT(0)
> +
> +#define RCANFD_GCFG_TPRI               BIT(0)
> +#define RCANFD_GCFG_DCE                        BIT(1)
> +#define RCANFD_GCFG_DCS                        BIT(4)
> +#define RCANFD_GCFG_CMPOC              BIT(5)

What reference are the register layouts based on? This bit, for
instance, is marked reserved in R-Car-Gen3-rev0.51e.pdf, and many are
named differently.

CU
Uli
Ramesh Shanmugasundaram June 3, 2016, 6:42 a.m. UTC | #12
Hi Uli,

Thanks for the review

> Thank you for your patch.

> 

> On Thu, Jun 2, 2016 at 11:45 AM, Ramesh Shanmugasundaram

> <ramesh.shanmugasundaram@bp.renesas.com> wrote:

> [...]

> > diff --git a/drivers/net/can/rcar/rcar_canfd.c

> > b/drivers/net/can/rcar/rcar_canfd.c

> > new file mode 100644

> > index 0000000..e198732

> > --- /dev/null

> > +++ b/drivers/net/can/rcar/rcar_canfd.c

> > @@ -0,0 +1,1624 @@

> > +/* Renesas R-Car CAN FD device driver

> > + *

> > + * Copyright (C) 2015 Renesas Electronics Corp.

> > + *

> > + * This program is free software; you can redistribute  it and/or

> > +modify it

> > + * under  the terms of  the GNU General  Public License as published

> > +by the

> > + * Free Software Foundation;  either version 2 of the  License, or

> > +(at your

> > + * option) any later version.

> > + */

> > +

> > +/* The R-Car CAN FD controller can operate in either one of the below

> > +two modes

> > + *  - CAN FD only mode

> > + *  - Classical CAN (CAN 2.0) only mode

> > + *

> > + * This driver puts the controller in CAN FD only mode by default. In

> > +this

> > + * mode, the controller acts as a CAN FD node that can also

> > +interoperate with

> > + * CAN 2.0 nodes.

> > + *

> > + * As of now, this driver does not support the Classical CAN (CAN

> > +2.0) mode,

> > + * which is handled by a different register map compared to CAN FD only

> mode.

> > + */

> > +

> > +#include <linux/module.h>

> > +#include <linux/moduleparam.h>

> > +#include <linux/kernel.h>

> > +#include <linux/types.h>

> > +#include <linux/interrupt.h>

> > +#include <linux/errno.h>

> > +#include <linux/netdevice.h>

> > +#include <linux/platform_device.h>

> > +#include <linux/can/led.h>

> > +#include <linux/can/dev.h>

> > +#include <linux/clk.h>

> > +#include <linux/of.h>

> > +#include <linux/of_device.h>

> > +#include <linux/bitmap.h>

> > +#include <linux/bitops.h>

> > +#include <linux/iopoll.h>

> > +

> > +#define RCANFD_DRV_NAME                        "rcar_canfd"

> > +

> > +#define RCANFD_FIFO_DEPTH              8       /* Tx FIFO depth */

> > +#define RCANFD_NAPI_WEIGHT             8       /* Rx poll quota */

> > +

> > +#define RCANFD_NUM_CHANNELS            2       /* Two channels max */

> > +#define RCANFD_CHANNELS_MASK           BIT((RCANFD_NUM_CHANNELS) - 1)

> > +

> > +/* Rx FIFO is a global resource of the controller. There are 8 such

> > +FIFOs

> > + * available. Each channel gets a dedicated Rx FIFO (i.e.) the

> > +channel

> > + * number is added to RFFIFO index.

> > + */

> > +#define RCANFD_RFFIFO_IDX              0

> > +

> > +/* Tx/Rx or Common FIFO is a per channel resource. Each channel has 3

> > +Common

> > + * FIFOs dedicated to them. Use the first (index 0) FIFO out of the 3

> for Tx.

> > + */

> > +#define RCANFD_CFFIFO_IDX              0

> > +

> > +/* Global register bits */

> > +#define RCANFD_GINTF_CANFD             BIT(0)

> > +

> > +#define RCANFD_GCFG_TPRI               BIT(0)

> > +#define RCANFD_GCFG_DCE                        BIT(1)

> > +#define RCANFD_GCFG_DCS                        BIT(4)

> > +#define RCANFD_GCFG_CMPOC              BIT(5)

> 

> What reference are the register layouts based on? This bit, for instance,

> is marked reserved in R-Car-Gen3-rev0.51e.pdf, and many are named

> differently.


It is based on rev0.51e Gen3 h/w manual. This controller has two register maps within itself for classical CAN only mode or CAN FD only mode. Section 52A.7.3.1 defines GCFG classical CAN only mode where bit 5 is reserved and Section 52A.9.3.1 defines GCFG CAN FD mode where bit 5 is defined as CMPOC.

It is explained in the initial comments section of this driver 

-------------
+/* The R-Car CAN FD controller can operate in either one of the below two modes
+ *  - CAN FD only mode
+ *  - Classical CAN (CAN 2.0) only mode
+ *
+ * This driver puts the controller in CAN FD only mode by default. In this
+ * mode, the controller acts as a CAN FD node that can also interoperate with
+ * CAN 2.0 nodes.
+ *
+ * As of now, this driver does not support the Classical CAN (CAN 2.0) mode,
+ * which is handled by a different register map compared to CAN FD only mode
--------------

Thanks,
Ramesh
Ulrich Hecht June 3, 2016, 5:03 p.m. UTC | #13
On Fri, Jun 3, 2016 at 8:42 AM, Ramesh Shanmugasundaram
<ramesh.shanmugasundaram@bp.renesas.com> wrote:
> Hi Uli,
>
> Thanks for the review
>
>> Thank you for your patch.
>>
>> On Thu, Jun 2, 2016 at 11:45 AM, Ramesh Shanmugasundaram
>> <ramesh.shanmugasundaram@bp.renesas.com> wrote:
>> [...]
>> > diff --git a/drivers/net/can/rcar/rcar_canfd.c
>> > b/drivers/net/can/rcar/rcar_canfd.c
>> > new file mode 100644
>> > index 0000000..e198732
>> > --- /dev/null
>> > +++ b/drivers/net/can/rcar/rcar_canfd.c
>> > @@ -0,0 +1,1624 @@
>> > +/* Renesas R-Car CAN FD device driver
>> > + *
>> > + * Copyright (C) 2015 Renesas Electronics Corp.
>> > + *
>> > + * This program is free software; you can redistribute  it and/or
>> > +modify it
>> > + * under  the terms of  the GNU General  Public License as published
>> > +by the
>> > + * Free Software Foundation;  either version 2 of the  License, or
>> > +(at your
>> > + * option) any later version.
>> > + */
>> > +
>> > +/* The R-Car CAN FD controller can operate in either one of the below
>> > +two modes
>> > + *  - CAN FD only mode
>> > + *  - Classical CAN (CAN 2.0) only mode
>> > + *
>> > + * This driver puts the controller in CAN FD only mode by default. In
>> > +this
>> > + * mode, the controller acts as a CAN FD node that can also
>> > +interoperate with
>> > + * CAN 2.0 nodes.
>> > + *
>> > + * As of now, this driver does not support the Classical CAN (CAN
>> > +2.0) mode,
>> > + * which is handled by a different register map compared to CAN FD only
>> mode.
>> > + */
>> > +
>> > +#include <linux/module.h>
>> > +#include <linux/moduleparam.h>
>> > +#include <linux/kernel.h>
>> > +#include <linux/types.h>
>> > +#include <linux/interrupt.h>
>> > +#include <linux/errno.h>
>> > +#include <linux/netdevice.h>
>> > +#include <linux/platform_device.h>
>> > +#include <linux/can/led.h>
>> > +#include <linux/can/dev.h>
>> > +#include <linux/clk.h>
>> > +#include <linux/of.h>
>> > +#include <linux/of_device.h>
>> > +#include <linux/bitmap.h>
>> > +#include <linux/bitops.h>
>> > +#include <linux/iopoll.h>
>> > +
>> > +#define RCANFD_DRV_NAME                        "rcar_canfd"
>> > +
>> > +#define RCANFD_FIFO_DEPTH              8       /* Tx FIFO depth */
>> > +#define RCANFD_NAPI_WEIGHT             8       /* Rx poll quota */
>> > +
>> > +#define RCANFD_NUM_CHANNELS            2       /* Two channels max */
>> > +#define RCANFD_CHANNELS_MASK           BIT((RCANFD_NUM_CHANNELS) - 1)
>> > +
>> > +/* Rx FIFO is a global resource of the controller. There are 8 such
>> > +FIFOs
>> > + * available. Each channel gets a dedicated Rx FIFO (i.e.) the
>> > +channel
>> > + * number is added to RFFIFO index.
>> > + */
>> > +#define RCANFD_RFFIFO_IDX              0
>> > +
>> > +/* Tx/Rx or Common FIFO is a per channel resource. Each channel has 3
>> > +Common
>> > + * FIFOs dedicated to them. Use the first (index 0) FIFO out of the 3
>> for Tx.
>> > + */
>> > +#define RCANFD_CFFIFO_IDX              0
>> > +
>> > +/* Global register bits */
>> > +#define RCANFD_GINTF_CANFD             BIT(0)
>> > +
>> > +#define RCANFD_GCFG_TPRI               BIT(0)
>> > +#define RCANFD_GCFG_DCE                        BIT(1)
>> > +#define RCANFD_GCFG_DCS                        BIT(4)
>> > +#define RCANFD_GCFG_CMPOC              BIT(5)
>>
>> What reference are the register layouts based on? This bit, for instance,
>> is marked reserved in R-Car-Gen3-rev0.51e.pdf, and many are named
>> differently.
>
> It is based on rev0.51e Gen3 h/w manual. This controller has two register maps within itself for classical CAN only mode or CAN FD only mode. Section 52A.7.3.1 defines GCFG classical CAN only mode where bit 5 is reserved and Section 52A.9.3.1 defines GCFG CAN FD mode where bit 5 is defined as CMPOC.

Thanks; I missed that every register is described twice.

Nevertheless, names often vary more or less subtly between your patch
and the specs, making it very hard to review. Some have letters added,
some have letters removed, and some are just plain confusing. For
instance, RCANFD_DCFG_* apparently does not describe, as one might
think, RSCFDnCFDCmDCFG, but RSCFDnCFDCmFDCFG. These names are, of
course, completely ridiculous, but inventing a new set makes things
even worse, IMO.

At least for the bits, I'd stick with the names given in the
datasheet. They usually make a modicum of sense, and it makes it way
easier to search for them. It would also help if the bits were sorted
consistently.

CU
Uli
Oliver Hartkopp June 3, 2016, 5:15 p.m. UTC | #14
On 06/03/2016 07:03 PM, Ulrich Hecht wrote:

> Thanks; I missed that every register is described twice.
>
> Nevertheless, names often vary more or less subtly between your patch
> and the specs, making it very hard to review. Some have letters added,
> some have letters removed, and some are just plain confusing. For
> instance, RCANFD_DCFG_* apparently does not describe, as one might
> think, RSCFDnCFDCmDCFG, but RSCFDnCFDCmFDCFG. These names are, of
> course, completely ridiculous, but inventing a new set makes things
> even worse, IMO.

???

You suggest to use 'completely ridiculous' definitions in favor to 
definitions that have a proper name space RCANFD_ ?

When there is a more readable way that maintains proper readable code 
there's no reason to adopt crappy definitions just because some chip 
designer has no clue how to design proper register names.

When there's some mapping from RSCFDnCFDCmFDCFG to RCANFD_DCFG_* this 
could be mentioned in the comments.

But I'm totally against these blurry upper/lower case letter stuff for 
register definitions.

Regards,
Oliver


>
> At least for the bits, I'd stick with the names given in the
> datasheet. They usually make a modicum of sense, and it makes it way
> easier to search for them. It would also help if the bits were sorted
> consistently.
>
> CU
> Uli
>
David Miller June 3, 2016, 6:39 p.m. UTC | #15
From: Oliver Hartkopp <socketcan@hartkopp.net>
Date: Fri, 3 Jun 2016 19:15:29 +0200

> On 06/03/2016 07:03 PM, Ulrich Hecht wrote:
> 
>> Thanks; I missed that every register is described twice.
>>
>> Nevertheless, names often vary more or less subtly between your patch
>> and the specs, making it very hard to review. Some have letters added,
>> some have letters removed, and some are just plain confusing. For
>> instance, RCANFD_DCFG_* apparently does not describe, as one might
>> think, RSCFDnCFDCmDCFG, but RSCFDnCFDCmFDCFG. These names are, of
>> course, completely ridiculous, but inventing a new set makes things
>> even worse, IMO.
> 
> ???
> 
> You suggest to use 'completely ridiculous' definitions in favor to
> definitions that have a proper name space RCANFD_ ?
> 
> When there is a more readable way that maintains proper readable code
> there's no reason to adopt crappy definitions just because some chip
> designer has no clue how to design proper register names.
> 
> When there's some mapping from RSCFDnCFDCmFDCFG to RCANFD_DCFG_* this
> could be mentioned in the comments.
> 
> But I'm totally against these blurry upper/lower case letter stuff for
> register definitions.

I agree with Oliver, these StuDlyCaPS names used in the spec should
not be used in the driver, they are completely unreadable.
Ramesh Shanmugasundaram June 7, 2016, 1:18 p.m. UTC | #16
> > On 06/03/2016 07:03 PM, Ulrich Hecht wrote:
> >
> >> Thanks; I missed that every register is described twice.
> >>
> >> Nevertheless, names often vary more or less subtly between your patch
> >> and the specs, making it very hard to review. Some have letters
> >> added, some have letters removed, and some are just plain confusing.
> >> For instance, RCANFD_DCFG_* apparently does not describe, as one
> >> might think, RSCFDnCFDCmDCFG, but RSCFDnCFDCmFDCFG. These names are,
> >> of course, completely ridiculous, but inventing a new set makes
> >> things even worse, IMO.
> >
> > ???
> >
> > You suggest to use 'completely ridiculous' definitions in favor to
> > definitions that have a proper name space RCANFD_ ?
> >
> > When there is a more readable way that maintains proper readable code
> > there's no reason to adopt crappy definitions just because some chip
> > designer has no clue how to design proper register names.
> >
> > When there's some mapping from RSCFDnCFDCmFDCFG to RCANFD_DCFG_* this
> > could be mentioned in the comments.
> >
> > But I'm totally against these blurry upper/lower case letter stuff for
> > register definitions.
> 
> I agree with Oliver, these StuDlyCaPS names used in the spec should not be
> used in the driver, they are completely unreadable.

Thanks Oliver, Dave for your inputs.

Hi Uli,

I have added comments to the readable register set mapping them to the clumsy name in h/w manual to aid your review. I have kept the bit name definitions within register exactly as in h/w manual. E.g.

+/* RSCFDnCFDGSTS */
+#define RCANFD_GSTS_GRAMINIT		BIT(3)
+#define RCANFD_GSTS_GSLPSTS		BIT(2)
+#define RCANFD_GSTS_GHLTSTS		BIT(1)
+#define RCANFD_GSTS_GRSTSTS		BIT(0)

I have also sorted the bit definition ordering from MSB to LSB. I will send out the updated patch set next. I hope this addresses your concern.

Please note that I am planning to add classical CAN only mode support next (after the current patch set is accepted). The code is designed to support both modes and hence I have classified the register definitions as "common register set" & "CAN FD specific register set". In future, I will just add the "Classical CAN specific register set" alone without much code re-org.

Thanks,
Ramesh
Ulrich Hecht June 13, 2016, 8:42 a.m. UTC | #17
Thanks for the patch, this is a lot easier to handle.

On Wed, Jun 8, 2016 at 8:38 AM, Ramesh Shanmugasundaram
<ramesh.shanmugasundaram@bp.renesas.com> wrote:
[...]
> diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
> new file mode 100644
> index 0000000..9f1f513
> --- /dev/null
> +++ b/drivers/net/can/rcar/rcar_canfd.c
> @@ -0,0 +1,1695 @@
> +/* Renesas R-Car CAN FD device driver
> + *
> + * Copyright (C) 2015 Renesas Electronics Corp.
> + *
> + * This program is free software; you can redistribute  it and/or modify it
> + * under  the terms of  the GNU General  Public License as published by the
> + * Free Software Foundation;  either version 2 of the  License, or (at your
> + * option) any later version.
> + */
> +
> +/* The R-Car CAN FD controller can operate in either one of the below two modes
> + *  - CAN FD only mode
> + *  - Classical CAN (CAN 2.0) only mode
> + *
> + * This driver puts the controller in CAN FD only mode by default. In this
> + * mode, the controller acts as a CAN FD node that can also interoperate with
> + * CAN 2.0 nodes.
> + *
> + * As of now, this driver does not support the Classical CAN (CAN 2.0) mode,
> + * which is handled by a different register map compared to CAN FD only mode.
> + *
> + * Note: The h/w manual register naming convention is clumsy and not acceptable
> + * to use as it is in the driver. However, those names are added as comments
> + * wherever it is modified to a readable name.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/moduleparam.h>
> +#include <linux/kernel.h>
> +#include <linux/types.h>
> +#include <linux/interrupt.h>
> +#include <linux/errno.h>
> +#include <linux/netdevice.h>
> +#include <linux/platform_device.h>
> +#include <linux/can/led.h>
> +#include <linux/can/dev.h>
> +#include <linux/clk.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/bitmap.h>
> +#include <linux/bitops.h>
> +#include <linux/iopoll.h>
> +
> +#define RCANFD_DRV_NAME                        "rcar_canfd"
> +
> +/* Global register bits */
> +
> +/* RSCFDnCFDGRMCFG */
> +#define RCANFD_GRMCFG_RCMC             BIT(0)
> +
> +/* RSCFDnCFDGCFG */
> +#define RCANFD_GCFG_CMPOC              BIT(5)
> +#define RCANFD_GCFG_DCS                        BIT(4)
> +#define RCANFD_GCFG_DCE                        BIT(1)
> +#define RCANFD_GCFG_TPRI               BIT(0)
> +
> +/* RSCFDnCFDGCTR */
> +#define RCANFD_GCTR_TSRST              BIT(16)
> +#define RCANFD_GCTR_CFMPOFIE           BIT(11)
> +#define RCANFD_GCTR_THLEIE             BIT(10)
> +#define RCANFD_GCTR_MEIE               BIT(9)
> +#define RCANFD_GCTR_DEIE               BIT(8)
> +#define RCANFD_GCTR_GSLPR              BIT(2)
> +#define RCANFD_GCTR_GMDC_MASK          (0x3)
> +#define RCANFD_GCTR_GMDC_GOPM          (0x0)
> +#define RCANFD_GCTR_GMDC_GRESET                (0x1)
> +#define RCANFD_GCTR_GMDC_GTEST         (0x2)
> +
> +/* RSCFDnCFDGSTS */
> +#define RCANFD_GSTS_GRAMINIT           BIT(3)
> +#define RCANFD_GSTS_GSLPSTS            BIT(2)
> +#define RCANFD_GSTS_GHLTSTS            BIT(1)
> +#define RCANFD_GSTS_GRSTSTS            BIT(0)
> +/* Non-operational status */
> +#define RCANFD_GSTS_GNOPM              (BIT(0) | BIT(1) | BIT(2) | BIT(3))
> +
> +/* RSCFDnCFDGERFL */
> +#define RCANFD_GERFL_EEF1              BIT(17)
> +#define RCANFD_GERFL_EEF0              BIT(16)
> +#define RCANFD_GERFL_CMPOF             BIT(3)
> +#define RCANFD_GERFL_THLES             BIT(2)
> +#define RCANFD_GERFL_MES               BIT(1)
> +#define RCANFD_GERFL_DEF               BIT(0)
> +
> +#define RCANFD_GERFL_ERR(x)            ((x) & (RCANFD_GERFL_EEF1 |\
> +                                               RCANFD_GERFL_EEF0 |\
> +                                               RCANFD_GERFL_MES |\
> +                                               RCANFD_GERFL_CMPOF))
> +
> +/* AFL Rx rules registers */
> +
> +/* RSCFDnCFDGAFLCFG0 */
> +#define RCANFD_GAFLCFG_SETRNC(n, x)    (((x) & 0xff) << (24 - n * 8))
> +#define RCANFD_GAFLCFG_GETRNC(n, x)    (((x) >> (24 - n * 8)) & 0xff)
> +
> +/* RSCFDnCFDGAFLECTR */
> +#define RCANFD_GAFLECTR_AFLDAE         BIT(8)
> +#define RCANFD_GAFLECTR_AFLPN(x)       ((x) & 0x1f)
> +
> +/* RSCFDnCFDGAFLIDj */
> +#define RCANFD_GAFLID_GAFLLB           BIT(29)
> +
> +/* RSCFDnCFDGAFLP1_j */
> +#define RCANFD_GAFLP1_GAFLFDP(x)       (1 << (x))
> +
> +/* Channel register bits */
> +
> +/* RSCFDnCFDCmNCFG */
> +#define RCANFD_NCFG_NTSEG2(x)          (((x) & 0x1f) << 24)
> +#define RCANFD_NCFG_NTSEG1(x)          (((x) & 0x7f) << 16)
> +#define RCANFD_NCFG_NSJW(x)            (((x) & 0x1f) << 11)
> +#define RCANFD_NCFG_NBRP(x)            (((x) & 0x3ff) << 0)
> +
> +/* RSCFDnCFDCmCTR */
> +#define RCANFD_CCTR_CTME               BIT(24)
> +#define RCANFD_CCTR_ERRD               BIT(23)
> +#define RCANFD_CCTR_BOM_MASK           (0x3 << 21)
> +#define RCANFD_CCTR_BOM_ISO            (0x0 << 21)
> +#define RCANFD_CCTR_BOM_BENTRY         (0x1 << 21)
> +#define RCANFD_CCTR_BOM_BEND           (0x2 << 21)
> +#define RCANFD_CCTR_TDCVFIE            BIT(19)
> +#define RCANFD_CCTR_SOCOIE             BIT(18)
> +#define RCANFD_CCTR_EOCOIE             BIT(17)
> +#define RCANFD_CCTR_TAIE               BIT(16)
> +#define RCANFD_CCTR_ALIE               BIT(15)
> +#define RCANFD_CCTR_BLIE               BIT(14)
> +#define RCANFD_CCTR_OLIE               BIT(13)
> +#define RCANFD_CCTR_BORIE              BIT(12)
> +#define RCANFD_CCTR_BOEIE              BIT(11)
> +#define RCANFD_CCTR_EPIE               BIT(10)
> +#define RCANFD_CCTR_EWIE               BIT(9)
> +#define RCANFD_CCTR_BEIE               BIT(8)
> +#define RCANFD_CCTR_CSLPR              BIT(2)
> +#define RCANFD_CCTR_CHMDC_MASK         (0x3)
> +#define RCANFD_CCTR_CHDMC_COPM         (0x0)
> +#define RCANFD_CCTR_CHDMC_CRESET       (0x1)
> +#define RCANFD_CCTR_CHDMC_CHLT         (0x2)
> +
> +/* RSCFDnCFDCmSTS */
> +#define RCANFD_CSTS_COMSTS             BIT(7)
> +#define RCANFD_CSTS_RECSTS             BIT(6)
> +#define RCANFD_CSTS_TRMSTS             BIT(5)
> +#define RCANFD_CSTS_BOSTS              BIT(4)
> +#define RCANFD_CSTS_EPSTS              BIT(3)
> +#define RCANFD_CSTS_SLPSTS             BIT(2)
> +#define RCANFD_CSTS_HLTSTS             BIT(1)
> +#define RCANFD_CSTS_CRSTSTS            BIT(0)
> +
> +#define RCANFD_CSTS_TECCNT(x)          (((x) >> 24) & 0xff)
> +#define RCANFD_CSTS_RECCNT(x)          (((x) >> 16) & 0xff)
> +
> +/* RSCFDnCFDCmERFL */
> +#define RCANFD_CERFL_ADERR             BIT(14)
> +#define RCANFD_CERFL_B0ERR             BIT(13)
> +#define RCANFD_CERFL_B1ERR             BIT(12)
> +#define RCANFD_CERFL_CERR              BIT(11)
> +#define RCANFD_CERFL_AERR              BIT(10)
> +#define RCANFD_CERFL_FERR              BIT(9)
> +#define RCANFD_CERFL_SERR              BIT(8)
> +#define RCANFD_CERFL_ALF               BIT(7)
> +#define RCANFD_CERFL_BLF               BIT(6)
> +#define RCANFD_CERFL_OVLF              BIT(5)
> +#define RCANFD_CERFL_BORF              BIT(4)
> +#define RCANFD_CERFL_BOEF              BIT(3)
> +#define RCANFD_CERFL_EPF               BIT(2)
> +#define RCANFD_CERFL_EWF               BIT(1)
> +#define RCANFD_CERFL_BEF               BIT(0)
> +
> +#define RCANFD_CERFL_ERR(x)            ((x) & (0x7fff)) /* above bits 14:0 */
> +
> +/* RSCFDnCFDCmDCFG */
> +#define RCANFD_DCFG_DSJW(x)            (((x) & 0x7) << 24)
> +#define RCANFD_DCFG_DTSEG2(x)          (((x) & 0x7) << 20)
> +#define RCANFD_DCFG_DTSEG1(x)          (((x) & 0xf) << 16)
> +#define RCANFD_DCFG_DBRP(x)            (((x) & 0xff) << 0)
> +
> +/* RSCFDnCFDCmFDCFG */
> +#define RCANFD_FDCFG_TDCE              BIT(9)
> +#define RCANFD_FDCFG_TDCOC             BIT(8)
> +#define RCANFD_FDCFG_TDCO(x)           (((x) & 0x7f) >> 16)
> +
> +/* RSCFDnCFDRFCCx */
> +#define RCANFD_RFCC_RFIM               BIT(12)
> +#define RCANFD_RFCC_RFDC(x)            (((x) & 0x7) << 8)
> +#define RCANFD_RFCC_RFPLS(x)           (((x) & 0x7) << 4)
> +#define RCANFD_RFCC_RFIE               BIT(1)
> +#define RCANFD_RFCC_RFE                        BIT(0)
> +
> +/* RSCFDnCFDRFSTSx */
> +#define RCANFD_RFSTS_RFIF              BIT(3)
> +#define RCANFD_RFSTS_RFMLT             BIT(2)
> +#define RCANFD_RFSTS_RFFLL             BIT(1)
> +#define RCANFD_RFSTS_RFEMP             BIT(0)
> +
> +/* RSCFDnCFDRFIDx */
> +#define RCANFD_RFID_RFIDE              BIT(31)
> +#define RCANFD_RFID_RFRTR              BIT(30)
> +
> +/* RSCFDnCFDRFPTRx */
> +#define RCANFD_RFPTR_RFDLC(x)          (((x) >> 28) & 0xf)
> +#define RCANFD_RFPTR_RFPTR(x)          (((x) >> 16) & 0xfff)
> +#define RCANFD_RFPTR_RFTS(x)           (((x) >> 0) & 0xff)

That should be "(((x) >> 0) & 0xffff)".

> +
> +/* RSCFDnCFDRFFDSTSx */
> +#define RCANFD_RFFDSTS_RFFDF           BIT(2)
> +#define RCANFD_RFFDSTS_RFBRS           BIT(1)
> +#define RCANFD_RFFDSTS_RFESI           BIT(0)
> +
> +/* Common FIFO bits */
> +
> +/* RSCFDnCFDCFCCk */
> +#define RCANFD_CFCC_CFTML(x)           (((x) & 0xf) << 20)
> +#define RCANFD_CFCC_CFM(x)             (((x) & 0x3) << 16)
> +#define RCANFD_CFCC_CFIM               BIT(12)
> +#define RCANFD_CFCC_CFDC(x)            (((x) & 0x7) << 8)
> +#define RCANFD_CFCC_CFPLS(x)           (((x) & 0x7) << 4)
> +#define RCANFD_CFCC_CFTXIE             BIT(2)
> +#define RCANFD_CFCC_CFE                        BIT(0)
> +
> +/* RSCFDnCFDCFSTSk */
> +#define RCANFD_CFSTS_CFMC(x)           (((x) >> 8) & 0xff)
> +#define RCANFD_CFSTS_CFTXIF            BIT(4)
> +#define RCANFD_CFSTS_CFMLT             BIT(2)
> +#define RCANFD_CFSTS_CFFLL             BIT(1)
> +#define RCANFD_CFSTS_CFEMP             BIT(0)
> +
> +/* RSCFDnCFDCFIDk */
> +#define RCANFD_CFID_CFIDE              BIT(31)
> +#define RCANFD_CFID_CFRTR              BIT(30)
> +#define RCANFD_CFID_CFID_MASK(x)       ((x) & 0x1fffffff)
> +
> +/* RSCFDnCFDCFPTRk */
> +#define RCANFD_CFPTR_CFDLC(x)          (((x) & 0xf) << 28)
> +#define RCANFD_CFPTR_CFPTR(x)          (((x) & 0xfff) << 16)
> +#define RCANFD_CFPTR_CFTS(x)           (((x) & 0xff) << 0)
> +
> +/* RSCFDnCFDCFFDCSTSk */
> +#define RCANFD_CFFDCSTS_CFFDF          BIT(2)
> +#define RCANFD_CFFDCSTS_CFBRS          BIT(1)
> +#define RCANFD_CFFDCSTS_CFESI          BIT(0)
> +
> +/* This controller supports classical CAN only mode or CAN FD only mode. These
> + * modes are supported in two separate set of register maps & names. However,
> + * some of the register offsets are common for both modes. Those offsets are
> + * listed below as Common registers.
> + *
> + * The CAN FD only specific registers are listed separately and their names
> + * starts with RCANFD_F_xxx names. When classical CAN only specific registers
> + * are added, those specific registers can be prefixed as RCANFD_C_xxx.
> + */
> +
> +/* Common registers */
> +
> +/* RSCFDnCFDCmNCFG / RSCFDnCmCFG */
> +#define RCANFD_CCFG(m)                 (0x0000 + (0x10 * (m)))
> +/* RSCFDnCFDCmCTR / RSCFDnCmCTR */
> +#define RCANFD_CCTR(m)                 (0x0004 + (0x10 * (m)))
> +/* RSCFDnCFDCmSTS / RSCFDnCmSTS */
> +#define RCANFD_CSTS(m)                 (0x0008 + (0x10 * (m)))
> +/* RSCFDnCFDCmERFL / RSCFDnCmERFL */
> +#define RCANFD_CERFL(m)                        (0x000C + (0x10 * (m)))
> +
> +/* RSCFDnCFDGCFG / RSCFDnGCFG */
> +#define RCANFD_GCFG                    (0x0084)
> +/* RSCFDnCFDGCTR / RSCFDnGCTR */
> +#define RCANFD_GCTR                    (0x0088)
> +/* RSCFDnCFDGCTS / RSCFDnGCTS */
> +#define RCANFD_GSTS                    (0x008c)
> +/* RSCFDnCFDGERFL / RSCFDnGERFL */
> +#define RCANFD_GERFL                   (0x0090)
> +/* RSCFDnCFDGTSC / RSCFDnGTSC */
> +#define RCANFD_GTSC                    (0x0094)
> +/* RSCFDnCFDGAFLECTR / RSCFDnGAFLECTR */
> +#define RCANFD_GAFLECTR                        (0x0098)
> +/* RSCFDnCFDGAFLCFG0 / RSCFDnGAFLCFG0 */
> +#define RCANFD_GAFLCFG0                        (0x009c)
> +/* RSCFDnCFDGAFLCFG1 / RSCFDnGAFLCFG1 */
> +#define RCANFD_GAFLCFG1                        (0x00a0)
> +/* RSCFDnCFDRMNB / RSCFDnRMNB */
> +#define RCANFD_RMNB                    (0x00a4)
> +/* RSCFDnCFDRMND / RSCFDnRMND */
> +#define RCANFD_RMND(y)                 (0x00a8 + (0x04 * (y)))
> +
> +/* RSCFDnCFDRFCCx / RSCFDnRFCCx */
> +#define RCANFD_RFCC(x)                 (0x00b8 + (0x04 * (x)))
> +/* RSCFDnCFDRFSTSx / RSCFDnRFSTSx */
> +#define RCANFD_RFSTS(x)                        (0x00d8 + (0x04 * (x)))
> +/* RSCFDnCFDRFPCTRx / RSCFDnRFPCTRx */
> +#define RCANFD_RFPCTR(x)               (0x00f8 + (0x04 * (x)))
> +
> +/* Common FIFO Control registers */
> +
> +/* RSCFDnCFDCFCCx / RSCFDnCFCCx */
> +#define RCANFD_CFCC(ch, idx)           (0x0118 + (0x0c * (ch)) + \
> +                                        (0x04 * (idx)))
> +/* RSCFDnCFDCFSTSx / RSCFDnCFSTSx */
> +#define RCANFD_CFSTS(ch, idx)          (0x0178 + (0x0c * (ch)) + \
> +                                        (0x04 * (idx)))
> +/* RSCFDnCFDCFPCTRx / RSCFDnCFPCTRx */
> +#define RCANFD_CFPCTR(ch, idx)         (0x01d8 + (0x0c * (ch)) + \
> +                                        (0x04 * (idx)))
> +
> +/* RSCFDnCFDFESTS / RSCFDnFESTS */
> +#define RCANFD_FESTS                   (0x0238)
> +/* RSCFDnCFDFFSTS / RSCFDnFFSTS */
> +#define RCANFD_FFSTS                   (0x023c)
> +/* RSCFDnCFDFMSTS / RSCFDnFMSTS */
> +#define RCANFD_FMSTS                   (0x0240)
> +/* RSCFDnCFDRFISTS / RSCFDnRFISTS */
> +#define RCANFD_RFISTS                  (0x0244)
> +/* RSCFDnCFDCFRISTS / RSCFDnCFRISTS */
> +#define RCANFD_CFRISTS                 (0x0248)
> +/* RSCFDnCFDCFTISTS / RSCFDnCFTISTS */
> +#define RCANFD_CFTISTS                 (0x024c)
> +
> +/* RSCFDnCFDTMCp / RSCFDnTMCp */
> +#define RCANFD_TMC(p)                  (0x0250 + (0x01 * (p)))
> +/* RSCFDnCFDTMSTSp / RSCFDnTMSTSp */
> +#define RCANFD_TMSTS(p)                        (0x02d0 + (0x01 * (p)))
> +
> +/* RSCFDnCFDTMTRSTSp / RSCFDnTMTRSTSp */
> +#define RCANFD_TMTRSTS(y)              (0x0350 + (0x04 * (y)))
> +/* RSCFDnCFDTMTARSTSp / RSCFDnTMTARSTSp */
> +#define RCANFD_TMTARSTS(y)             (0x0360 + (0x04 * (y)))
> +/* RSCFDnCFDTMTCSTSp / RSCFDnTMTCSTSp */
> +#define RCANFD_TMTCSTS(y)              (0x0370 + (0x04 * (y)))
> +/* RSCFDnCFDTMTASTSp / RSCFDnTMTASTSp */
> +#define RCANFD_TMTASTS(y)              (0x0380 + (0x04 * (y)))
> +/* RSCFDnCFDTMIECy / RSCFDnTMIECy */
> +#define RCANFD_TMIEC(y)                        (0x0390 + (0x04 * (y)))
> +
> +/* RSCFDnCFDTXQCCm / RSCFDnTXQCCm */
> +#define RCANFD_TXQCC(m)                        (0x03a0 + (0x04 * (m)))
> +/* RSCFDnCFDTXQSTSm / RSCFDnTXQSTSm */
> +#define RCANFD_TXQSTS(m)               (0x03c0 + (0x04 * (m)))
> +/* RSCFDnCFDTXQPCTRm / RSCFDnTXQPCTRm */
> +#define RCANFD_TXQPCTR(m)              (0x03e0 + (0x04 * (m)))
> +
> +/* RSCFDnCFDTHLCCm / RSCFDnTHLCCm */
> +#define RCANFD_THLCC(m)                        (0x0400 + (0x04 * (m)))
> +/* RSCFDnCFDTHLSTSm / RSCFDnTHLSTSm */
> +#define RCANFD_THLSTS(m)               (0x0420 + (0x04 * (m)))
> +/* RSCFDnCFDTHLPCTRm / RSCFDnTHLPCTRm */
> +#define RCANFD_THLPCTR(m)              (0x0440 + (0x04 * (m)))
> +
> +/* RSCFDnCFDGTINTSTS0 / RSCFDnGTINTSTS0 */
> +#define RCANFD_GTINTSTS0               (0x0460)
> +/* RSCFDnCFDGTINTSTS1 / RSCFDnGTINTSTS1 */
> +#define RCANFD_GTINTSTS1               (0x0464)
> +/* RSCFDnCFDGTSTCFG / RSCFDnGTSTCFG */
> +#define RCANFD_GTSTCFG                 (0x0468)
> +/* RSCFDnCFDGTSTCTR / RSCFDnGTSTCTR */
> +#define RCANFD_GTSTCTR                 (0x046c)
> +/* RSCFDnCFDGLOCKK / RSCFDnGLOCKK */
> +#define RCANFD_GLOCKK                  (0x047c)
> +/* RSCFDnCFDGRMCFG / RSCFDnGRMCFG */
> +#define RCANFD_GRMCFG                  (0x04fc)
> +
> +/* RSCFDnCFDGAFLIDj / RSCFDnGAFLIDj */
> +#define RCANFD_GAFLID(offset, j)       ((offset) + (0x10 * (j)))
> +/* RSCFDnCFDGAFLMj / RSCFDnGAFLMj */
> +#define RCANFD_GAFLM(offset, j)                ((offset) + 0x04 + (0x10 * (j)))
> +/* RSCFDnCFDGAFLP0j / RSCFDnGAFLP0j */
> +#define RCANFD_GAFLP0(offset, j)       ((offset) + 0x08 + (0x10 * (j)))
> +/* RSCFDnCFDGAFLP1j / RSCFDnGAFLP1j */
> +#define RCANFD_GAFLP1(offset, j)       ((offset) + 0x0c + (0x10 * (j)))
> +
> +/* CAN FD mode specific regsiter map */
> +
> +/* RSCFDnCFDCmXXX -> RCANFD_F_XXX(m) */
> +#define RCANFD_F_DCFG(m)               (0x0500 + (0x20 * (m)))
> +#define RCANFD_F_CFDCFG(m)             (0x0504 + (0x20 * (m)))
> +#define RCANFD_F_CFDCTR(m)             (0x0508 + (0x20 * (m)))
> +#define RCANFD_F_CFDSTS(m)             (0x050c + (0x20 * (m)))
> +#define RCANFD_F_CFDCRC(m)             (0x0510 + (0x20 * (m)))
> +
> +/* RSCFDnCFDGAFLXXXj offset */
> +#define RCANFD_F_GAFL_OFFSET           (0x1000)
> +
> +/* RSCFDnCFDRMXXXq -> RCANFD_F_RMXXX(q) */
> +#define RCANFD_F_RMID(q)               (0x2000 + (0x10 * (q)))
> +#define RCANFD_F_RMPTR(q)              (0x2004 + (0x10 * (q)))
> +#define RCANFD_F_RMFDSTS(q)            (0x2008 + (0x10 * (q)))

These should all be "+ (0x20 * (q))".

> +#define RCANFD_F_RMDF(q, b)            (0x200c + (0x04 * (b)) + (0x20 * (q)))
> +
> +/* RSCFDnCFDRFXXx -> RCANFD_F_RFXX(x) */
> +#define RCANFD_F_RFOFFSET              (0x3000)
> +#define RCANFD_F_RFID(x)               (RCANFD_F_RFOFFSET + (0x80 * (x)))
> +#define RCANFD_F_RFPTR(x)              (RCANFD_F_RFOFFSET + 0x04 + \
> +                                        (0x80 * (x)))
> +#define RCANFD_F_RFFDSTS(x)            (RCANFD_F_RFOFFSET + 0x08 + \
> +                                        (0x80 * (x)))
> +#define RCANFD_F_RFDF(x, df)           (RCANFD_F_RFOFFSET + 0x0c + \
> +                                        (0x80 * (x)) + (0x04 * (df)))
> +
> +/* RSCFDnCFDCFXXk -> RCANFD_F_CFXX(ch, k) */
> +#define RCANFD_F_CFOFFSET              (0x3400)
> +#define RCANFD_F_CFID(ch, idx)         (RCANFD_F_CFOFFSET + (0x180 * (ch)) + \
> +                                        (0x80 * (idx)))
> +#define RCANFD_F_CFPTR(ch, idx)                (RCANFD_F_CFOFFSET + 0x04 + \
> +                                        (0x180 * (ch)) + (0x80 * (idx)))
> +#define RCANFD_F_CFFDCSTS(ch, idx)     (RCANFD_F_CFOFFSET + 0x08 + \
> +                                        (0x180 * (ch)) + (0x80 * (idx)))
> +#define RCANFD_F_CFDF(ch, idx, df)     (RCANFD_F_CFOFFSET + 0x0c + \
> +                                        (0x180 * (ch)) + (0x80 * (idx)) + \
> +                                        (0x04 * (df)))
> +
> +/* RSCFDnCFDTMXXp -> RCANFD_F_TMXX(p) */
> +#define RCANFD_F_TMID(p)               (0x4000 + (0x20 * (p)))
> +#define RCANFD_F_TMPTR(p)              (0x4004 + (0x20 * (p)))
> +#define RCANFD_F_TMFDCTR(p)            (0x4008 + (0x20 * (p)))
> +#define RCANFD_F_TMDF(p, b)            (0x400c + (0x20 * (p)) + (0x04 * (b)))
> +
> +/* RSCFDnCFDTHLACCm */
> +#define RCANFD_F_THLACC(m)             (0x6000 + (0x04 * (m)))
> +/* RSCFDnCFDRPGACCr */
> +#define RCANFD_F_RPGACC(r)             (0x6400 + (0x04 * (r)))
[...]

Apart from that, all register addresses, offsets, bit positions and
masks check out. With the two issues fixed:

Reviewed-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>

CU
Uli
Ramesh Shanmugasundaram June 14, 2016, 7:23 a.m. UTC | #18
Hi Ulrich,

> Thanks for the patch, this is a lot easier to handle.

> 

[...]
> > +#define RCANFD_RFPTR_RFTS(x)           (((x) >> 0) & 0xff)

> 

> That should be "(((x) >> 0) & 0xffff)".

> 

> > +

[...]

> > +/* RSCFDnCFDRMXXXq -> RCANFD_F_RMXXX(q) */

> > +#define RCANFD_F_RMID(q)               (0x2000 + (0x10 * (q)))

> > +#define RCANFD_F_RMPTR(q)              (0x2004 + (0x10 * (q)))

> > +#define RCANFD_F_RMFDSTS(q)            (0x2008 + (0x10 * (q)))

> 

> These should all be "+ (0x20 * (q))".

> 

[...]
> 

> Apart from that, all register addresses, offsets, bit positions and masks

> check out. With the two issues fixed:

> 

> Reviewed-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>


Thank you for your time & review comments. I have fixed these typos and sent out a v7 patch set adding your Reviewed-by tag.

Thanks,
Ramesh
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/net/can/rcar_canfd.txt b/Documentation/devicetree/bindings/net/can/rcar_canfd.txt
new file mode 100644
index 0000000..4299bd8
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/can/rcar_canfd.txt
@@ -0,0 +1,86 @@ 
+Renesas R-Car CAN FD controller Device Tree Bindings
+----------------------------------------------------
+
+Required properties:
+- compatible: Must contain one or more of the following:
+  - "renesas,rcar-gen3-canfd" for R-Car Gen3 compatible controller.
+  - "renesas,r8a7795-canfd" for R8A7795 (R-Car H3) compatible controller.
+
+  When compatible with the generic version, nodes must list the
+  SoC-specific version corresponding to the platform first, followed by the
+  family-specific and/or generic versions.
+
+- reg: physical base address and size of the R-Car CAN FD register map.
+- interrupts: interrupt specifier for the Global & Channel interrupts
+- clocks: phandles and clock specifiers for 3 clock inputs.
+- clock-names: 3 clock input name strings: "fck", "canfd", "can_clk".
+- pinctrl-0: pin control group to be used for this controller.
+- pinctrl-names: must be "default".
+
+Required properties for "renesas,r8a7795-canfd" compatible:
+In R8A7795 SoC, canfd clock is a div6 clock and can be used by both CAN
+and CAN FD controller at the same time. It needs to be scaled to maximum
+frequency if any of these controllers use it. This is done using the
+below properties.
+
+- assigned-clocks: phandle of canfd clock.
+- assigned-clock-rates: maximum frequency of this clock.
+
+Each channel is represented as a child node. They can be enabled/disabled
+using "status" property.
+
+Example
+-------
+
+SoC common .dtsi file:
+
+		canfd: canfd@e66c0000 {
+			compatible = "renesas,r8a7795-canfd",
+				     "renesas,rcar-gen3-canfd";
+			reg = <0 0xe66c0000 0 0x8000>;
+			interrupts = <GIC_SPI 29 IRQ_TYPE_LEVEL_HIGH>,
+				   <GIC_SPI 30 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&cpg CPG_MOD 914>,
+			       <&cpg CPG_CORE R8A7795_CLK_CANFD>,
+			       <&can_clk>;
+			clock-names = "fck", "canfd", "can_clk";
+			assigned-clocks = <&cpg CPG_CORE R8A7795_CLK_CANFD>;
+			assigned-clock-rates = <40000000>;
+			power-domains = <&cpg>;
+			status = "disabled";
+
+			channel0 {
+				status = "disabled";
+			};
+
+			channel1 {
+				status = "disabled";
+			};
+		};
+
+Board specific .dts file:
+
+E.g. below enables Channel 1 alone in the board.
+
+&canfd {
+        pinctrl-0 = <&canfd1_pins>;
+        pinctrl-names = "default";
+        status = "okay";
+
+	channel1 {
+		status = "okay";
+	};
+};
+
+E.g. below enables Channel 0 alone in the board using External clock
+as fCAN clock.
+
+&canfd {
+        pinctrl-0 = <&canfd0_pins &can_clk_pins>;
+        pinctrl-names = "default";
+        status = "okay";
+
+	channel0 {
+		status = "okay";
+	};
+};
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 9a53c92..afbb5cd 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -3121,6 +3121,14 @@  bytes respectively. Such letter suffixes can also be entirely omitted.
 	ramdisk_size=	[RAM] Sizes of RAM disks in kilobytes
 			See Documentation/blockdev/ramdisk.txt.
 
+	rcar_canfd.testmode=
+			[HW] Selects the Controller test mode
+			Format: {0|1|2}
+			0	Test modes disabled (default)
+			1	Self-test internal loopback mode
+			2	Inter-channel test mode
+			Default: 0
+
 	rcu_nocbs=	[KNL]
 			In kernels built with CONFIG_RCU_NOCB_CPU=y, set
 			the specified list of CPUs to be no-callback CPUs.
diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig
index 0d40aef..0ecb4fe 100644
--- a/drivers/net/can/Kconfig
+++ b/drivers/net/can/Kconfig
@@ -114,6 +114,16 @@  config CAN_RCAR
 	  To compile this driver as a module, choose M here: the module will
 	  be called rcar_can.
 
+config CANFD_RCAR
+	tristate "Renesas R-Car CAN FD controller"
+	depends on ARCH_RENESAS || ARM
+	---help---
+	  Say Y here if you want to use CAN FD controller found on
+	  Renesas R-Car SoCs.
+
+	  To compile this driver as a module, choose M here: the module will
+	  be called rcar_canfd.
+
 config CAN_SUN4I
 	tristate "Allwinner A10 CAN controller"
 	depends on MACH_SUN4I || MACH_SUN7I || COMPILE_TEST
diff --git a/drivers/net/can/Makefile b/drivers/net/can/Makefile
index e3db0c8..401b150 100644
--- a/drivers/net/can/Makefile
+++ b/drivers/net/can/Makefile
@@ -25,6 +25,7 @@  obj-$(CONFIG_CAN_JANZ_ICAN3)	+= janz-ican3.o
 obj-$(CONFIG_CAN_MSCAN)		+= mscan/
 obj-$(CONFIG_CAN_M_CAN)		+= m_can/
 obj-$(CONFIG_CAN_RCAR)		+= rcar_can.o
+obj-$(CONFIG_CANFD_RCAR)	+= rcar_canfd.o
 obj-$(CONFIG_CAN_SJA1000)	+= sja1000/
 obj-$(CONFIG_CAN_SUN4I)		+= sun4i_can.o
 obj-$(CONFIG_CAN_TI_HECC)	+= ti_hecc.o
diff --git a/drivers/net/can/rcar_canfd.c b/drivers/net/can/rcar_canfd.c
new file mode 100644
index 0000000..6f85e25
--- /dev/null
+++ b/drivers/net/can/rcar_canfd.c
@@ -0,0 +1,1905 @@ 
+/* Renesas R-Car CAN FD device driver
+ *
+ * Copyright (C) 2015 Renesas Electronics Corp.
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <linux/platform_device.h>
+#include <linux/can/led.h>
+#include <linux/can/dev.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <linux/iopoll.h>
+
+#define RCANFD_DRV_NAME			"rcar_canfd"
+
+#define RCANFD_FIFO_DEPTH		8	/* Tx FIFO depth */
+#define RCANFD_NAPI_WEIGHT		8	/* Rx poll quota */
+
+#define RCANFD_NUM_CHANNELS		2
+#define RCANFD_CHANNELS_MASK		0x3	/* Two channels max */
+
+/* Rx FIFO is a global resource of the controller. There are 8 such FIFOs
+ * available. Each channel gets a dedicated Rx FIFO (i.e.) the channel
+ * number is added to RFFIFO index.
+ */
+#define RCANFD_RFFIFO_IDX		0
+
+/* Tx/Rx or Common FIFO is a per channel resource. Each channel has 3 Common
+ * FIFOs dedicated to them. Use the first (index 0) FIFO out of the 3 for Tx.
+ */
+#define RCANFD_CFFIFO_IDX		0
+
+/* Global register bits */
+#define RCANFD_GINTF_CANFD		BIT(0)
+
+#define RCANFD_GCFG_TPRI		BIT(0)
+#define RCANFD_GCFG_DCE			BIT(1)
+#define RCANFD_GCFG_DCS			BIT(4)
+#define RCANFD_GCFG_CMPOC		BIT(5)
+#define RCANFD_GCFG_EEFE		BIT(6)
+
+#define RCANFD_GCTR_SLPR		BIT(2)
+#define RCANFD_GCTR_MODEMASK		(0x3)
+#define RCANFD_GCTR_GOPM		(0x0)
+#define RCANFD_GCTR_GRESET		(0x1)
+#define RCANFD_GCTR_GHLT		(0x2)
+
+#define RCANFD_GCTR_DEIE		BIT(8)
+#define RCANFD_GCTR_MEIE		BIT(9)
+#define RCANFD_GCTR_THLEIE		BIT(10)
+#define RCANFD_GCTR_CFMPOFIE		BIT(11)
+#define RCANFD_GCTR_TSRST		BIT(16)
+
+#define RCANFD_GSTS_RAMINIT		BIT(3)
+#define RCANFD_GSTS_SLP			BIT(2)
+#define RCANFD_GSTS_HLT			BIT(1)
+#define RCANFD_GSTS_RESET		BIT(0)
+
+#define RCANFD_GSTS_GNOPM		(BIT(0) | BIT(1) | BIT(2) | BIT(3))
+
+/* Channel register bits */
+#define RCANFD_CCTR_CSLPR		BIT(2)
+#define RCANFD_CCTR_MODEMASK		(0x3)
+#define RCANFD_CCTR_COPM		(0x0)
+#define RCANFD_CCTR_CRESET		(0x1)
+#define RCANFD_CCTR_CHLT		(0x2)
+#define RCANFD_CCTR_CTMASK		(0x3 << 25)
+#define RCANFD_CCTR_CTMS_ILB		(0x3 << 25)
+#define RCANFD_CCTR_CTME		BIT(24)
+#define RCANFD_CCTR_ERRD		BIT(23)
+#define RCANFD_CCTR_BOMMASK		(0x3 << 21)
+#define RCANFD_CCTR_BOM_ENTRY		(0x1 << 21)
+#define RCANFD_CCTR_TDCVFIE		BIT(19)
+#define RCANFD_CCTR_SOCOIE		BIT(18)
+#define RCANFD_CCTR_EOCOIE		BIT(17)
+#define RCANFD_CCTR_TAIE		BIT(16)
+#define RCANFD_CCTR_ALIE		BIT(15)
+#define RCANFD_CCTR_BLIE		BIT(14)
+#define RCANFD_CCTR_OLIE		BIT(13)
+#define RCANFD_CCTR_BORIE		BIT(12)
+#define RCANFD_CCTR_BOEIE		BIT(11)
+#define RCANFD_CCTR_EPIE		BIT(10)
+#define RCANFD_CCTR_EWIE		BIT(9)
+#define RCANFD_CCTR_BEIE		BIT(8)
+
+#define RCANFD_CSTS_COM			BIT(7)
+#define RCANFD_CSTS_REC			BIT(6)
+#define RCANFD_CSTS_TRM			BIT(5)
+#define RCANFD_CSTS_BO			BIT(4)
+#define RCANFD_CSTS_EP			BIT(3)
+#define RCANFD_CSTS_SLP			BIT(2)
+#define RCANFD_CSTS_HALT		BIT(1)
+#define RCANFD_CSTS_RESET		BIT(0)
+
+#define RCANFD_CSTS_TECCNT(x)		(((x) >> 24) & 0xff)
+#define RCANFD_CSTS_RECCNT(x)		(((x) >> 16) & 0xff)
+
+/* Bit Configuration register */
+#define RCANFD_BRP(x)			(((x) & 0x3ff) << 0)
+#define RCANFD_SJW(x)			(((x) & 0x3) << 24)
+#define RCANFD_TSEG1(x)			(((x) & 0xf) << 16)
+#define RCANFD_TSEG2(x)			(((x) & 0x7) << 20)
+
+#define RCANFD_NR_BRP(x)		(((x) & 0x3ff) << 0)
+#define RCANFD_NR_SJW(x)		(((x) & 0x1f) << 11)
+#define RCANFD_NR_TSEG1(x)		(((x) & 0x7f) << 16)
+#define RCANFD_NR_TSEG2(x)		(((x) & 0x1f) << 24)
+
+#define RCANFD_DR_BRP(x)		(((x) & 0xff) << 0)
+#define RCANFD_DR_SJW(x)		(((x) & 0x7) << 24)
+#define RCANFD_DR_TSEG1(x)		(((x) & 0xf) << 16)
+#define RCANFD_DR_TSEG2(x)		(((x) & 0x7) << 20)
+
+/* Global Error flag bits */
+#define RCANFD_GERFL_EEF1		BIT(17)
+#define RCANFD_GERFL_EEF0		BIT(16)
+#define RCANFD_GERFL_CMPOF		BIT(3)
+#define RCANFD_GERFL_THLES		BIT(2)
+#define RCANFD_GERFL_MES		BIT(1)
+#define RCANFD_GERFL_DEF		BIT(0)
+
+#define RCANFD_GERFL_ERR(x)		((x) & (RCANFD_GERFL_EEF1 |\
+						RCANFD_GERFL_EEF0 |\
+						RCANFD_GERFL_MES |\
+						RCANFD_GERFL_CMPOF))
+
+/* Channel Error flag bits */
+#define RCANFD_CERFL_ADEF		BIT(14)
+#define RCANFD_CERFL_B0EF		BIT(13)
+#define RCANFD_CERFL_B1EF		BIT(12)
+#define RCANFD_CERFL_CEF		BIT(11)
+#define RCANFD_CERFL_AEF		BIT(10)
+#define RCANFD_CERFL_FEF		BIT(9)
+#define RCANFD_CERFL_SEF		BIT(8)
+#define RCANFD_CERFL_ALEF		BIT(7)
+#define RCANFD_CERFL_BLEF		BIT(6)
+#define RCANFD_CERFL_OLEF		BIT(5)
+#define RCANFD_CERFL_BOREF		BIT(4)
+#define RCANFD_CERFL_BOEEF		BIT(3)
+#define RCANFD_CERFL_EPEF		BIT(2)
+#define RCANFD_CERFL_EWEF		BIT(1)
+#define RCANFD_CERFL_BEF		BIT(0)
+
+#define RCANFD_CERFL_ERR(x)		((x) & (0x7fff)) /* above bits 14:0 */
+
+/* CAN FD specific registers */
+#define RCANFD_DCFG_TDCE		BIT(9)
+#define RCANFD_DCFG_TDCOC		BIT(8)
+#define RCANFD_DCFG_TDCO(x)		(((x) & 0x7f) >> 16)
+
+#define RCANFD_DCSTS_TDCR(x)		(((x) >> 0) & 0x7f)
+#define RCANFD_DCSTS_SOCCNT(x)		(((x) >> 24) & 0xff)
+#define RCANFD_DCSTS_EOCCNT(x)		(((x) >> 16) & 0xff)
+
+#define RCANFD_DCSTS_TDCVF		BIT(7)
+#define RCANFD_DCSTS_EOCO		BIT(8)
+#define RCANFD_DCSTS_SOCO		BIT(9)
+
+/* Rx FIFO bits */
+#define RCANFD_RFFIFO_RFIF		BIT(3)
+#define RCANFD_RFFIFO_RFMLT		BIT(2)
+#define RCANFD_RFFIFO_RFFLL		BIT(1)
+#define RCANFD_RFFIFO_RFEMP		BIT(0)
+
+#define RCANFD_RFFIFO_RFESI		BIT(0)
+#define RCANFD_RFFIFO_RFBRS		BIT(1)
+#define RCANFD_RFFIFO_RFFDF		BIT(2)
+
+#define RCANFD_RFFIFO_RFIDE		BIT(31)
+#define RCANFD_RFFIFO_RFRTR		BIT(30)
+
+#define RCANFD_RFFIFO_RFDLC(x)		(((x) >> 28) & 0xf)
+#define RCANFD_RFFIFO_RFPTR(x)		(((x) >> 16) & 0xfff)
+#define RCANFD_RFFIFO_RFTS(x)		(((x) >> 0) & 0xff)
+
+#define RCANFD_RFFIFO_RFIM		BIT(12)
+#define RCANFD_RFFIFO_RFDC(x)		(((x) & 0x7) << 8)
+#define RCANFD_RFFIFO_RFPLS(x)		(((x) & 0x7) << 4)
+#define RCANFD_RFFIFO_RFIE		BIT(1)
+#define RCANFD_RFFIFO_RFE		BIT(0)
+
+/* Common FIFO bits */
+#define RCANFD_CMFIFO_TML(x)		(((x) & 0xf) << 20)
+#define RCANFD_CMFIFO_M(x)		(((x) & 0x3) << 16)
+#define RCANFD_CMFIFO_CFIM		BIT(12)
+#define RCANFD_CMFIFO_DC(x)		(((x) & 0x7) << 8)
+#define RCANFD_CMFIFO_PLS(x)		(((x) & 0x7) << 4)
+#define RCANFD_CMFIFO_CFTXIE		BIT(2)
+#define RCANFD_CMFIFO_CFE		BIT(0)
+
+#define RCANFD_CMFIFO_CFTXIF		BIT(4)
+#define RCANFD_CMFIFO_CFMLT		BIT(2)
+#define RCANFD_CMFIFO_CFFLL		BIT(1)
+#define RCANFD_CMFIFO_CFEMP		BIT(0)
+#define RCANFD_CMFIFO_CFMC(x)		(((x) >> 8) & 0xff)
+
+#define RCANFD_CMFIFO_CFESI		BIT(0)
+#define RCANFD_CMFIFO_CFBRS		BIT(1)
+#define RCANFD_CMFIFO_CFFDF		BIT(2)
+
+#define RCANFD_CMFIFO_CFIDE		BIT(31)
+#define RCANFD_CMFIFO_CFRTR		BIT(30)
+#define RCANFD_CMFIFO_CFID(x)		((x) & 0x1fffffff)
+
+#define RCANFD_CMFIFO_CFDLC(x)		(((x) & 0xf) << 28)
+#define RCANFD_CMFIFO_CFPTR(x)		(((x) & 0xfff) << 16)
+#define RCANFD_CMFIFO_CFTS(x)		(((x) & 0xff) << 0)
+
+/* Global Test Config register */
+#define RCANFD_GTSTCFG_C0CBCE		BIT(0)
+#define RCANFD_GTSTCFG_C1CBCE		BIT(1)
+
+#define RCANFD_GTSTCTR_ICBCTME		BIT(0)
+
+/* AFL Rx rules registers */
+#define RCANFD_AFLCFG_SETRNC0(x)	(((x) & 0xff) << 24)
+#define RCANFD_AFLCFG_SETRNC1(x)	(((x) & 0xff) << 16)
+#define RCANFD_AFLCFG_GETRNC0(x)	(((x) >> 24) & 0xff)
+#define RCANFD_AFLCFG_GETRNC1(x)	(((x) >> 16) & 0xff)
+
+#define RCANFD_AFL_PAGENUM(entry)	((entry) / 16)
+
+#define RCANFD_AFLCTR_AFLDAE		BIT(8)
+#define RCANFD_AFLCTR_AFLPN(x)		((x) & 0x1f)
+#define RCANFD_CHANNEL_NUMRULES		1	/* only one rule per channel */
+#define RCANFD_AFLID_GAFLLB		BIT(29)
+#define RCANFD_AFLPTR1_RFFIFO(x)	(1 << (x))
+
+/* Common register map offsets */
+
+/* Nominal rate registers */
+#define RCANFD_CCFG(m)			(0x0000 + (0x10 * (m)))
+#define RCANFD_CCTR(m)			(0x0004 + (0x10 * (m)))
+#define RCANFD_CSTS(m)			(0x0008 + (0x10 * (m)))
+#define RCANFD_CERFL(m)			(0x000C + (0x10 * (m)))
+
+/* Global registers */
+#define RCANFD_GCFG			(0x0084)
+#define RCANFD_GCTR			(0x0088)
+#define RCANFD_GSTS			(0x008c)
+#define RCANFD_GERFL			(0x0090)
+#define RCANFD_GTSC			(0x0094)
+#define RCANFD_GAFLECTR			(0x0098)
+#define RCANFD_GAFLCFG0			(0x009c)
+#define RCANFD_GAFLCFG1			(0x00a0)
+#define RCANFD_RMNB			(0x00a4)
+
+#define RCANFD_RMND(y)			(0x00a8 + (0x04 * (y)))
+
+/* Rx FIFO Control registers */
+#define RCANFD_RFCC(x)			(0x00b8 + (0x04 * (x)))
+#define RCANFD_RFSTS(x)			(0x00d8 + (0x04 * (x)))
+#define RCANFD_RFPCTR(x)		(0x00f8 + (0x04 * (x)))
+
+/* Common FIFO Control registers */
+#define RCANFD_CFCC(ch, idx)		(0x0118 + (0x0c * (ch)) + \
+					 (0x04 * (idx)))
+#define RCANFD_CFSTS(ch, idx)		(0x0178 + (0x0c * (ch)) + \
+					 (0x04 * (idx)))
+#define RCANFD_CFPCTR(ch, idx)		(0x01d8 + (0x0c * (ch)) + \
+					 (0x04 * (idx)))
+
+#define RCANFD_FESTS			(0x0238)
+#define RCANFD_FFSTS			(0x023c)
+#define RCANFD_FMSTS			(0x0240)
+#define RCANFD_RFISTS			(0x0244)
+#define RCANFD_CFRISTS			(0x0248)
+#define RCANFD_CFTISTS			(0x024c)
+
+#define RCANFD_TMC(p)			(0x0250 + (0x01 * (p)))
+#define RCANFD_TMSTS(p)			(0x02d0 + (0x01 * (p)))
+
+#define RCANFD_TMTRSTS(y)		(0x0350 + (0x04 * (y)))
+#define RCANFD_TMTARSTS(y)		(0x0360 + (0x04 * (y)))
+#define RCANFD_TMTCSTS(y)		(0x0370 + (0x04 * (y)))
+#define RCANFD_TMTASTS(y)		(0x0380 + (0x04 * (y)))
+#define RCANFD_TMIEC(y)			(0x0390 + (0x04 * (y)))
+
+#define RCANFD_TXQCC(m)			(0x03a0 + (0x04 * (m)))
+#define RCANFD_TXQSTS(m)		(0x03c0 + (0x04 * (m)))
+#define RCANFD_TXQPCTR(m)		(0x03e0 + (0x04 * (m)))
+
+#define RCANFD_THLCC(m)			(0x0400 + (0x04 * (m)))
+#define RCANFD_THLSTS(m)		(0x0420 + (0x04 * (m)))
+#define RCANFD_THLPCTR(m)		(0x0440 + (0x04 * (m)))
+
+#define RCANFD_GTINTSTS0		(0x0460)
+#define RCANFD_GTINTSTS1		(0x0464)
+#define RCANFD_GTSTCFG			(0x0468)
+#define RCANFD_GTSTCTR			(0x046c)
+#define RCANFD_GLOCKK			(0x047c)
+#define RCANFD_GRMCFG			(0x04fc)
+
+/* Receive rule registers */
+#define RCANFD_GAFLID(offset, j)	((offset) + (0x10 * (j)))
+#define RCANFD_GAFLM(offset, j)		((offset) + 0x04 + (0x10 * (j)))
+#define RCANFD_GAFLP0(offset, j)	((offset) + 0x08 + (0x10 * (j)))
+#define RCANFD_GAFLP1(offset, j)	((offset) + 0x0c + (0x10 * (j)))
+
+/* CAN FD mode specific regsiter map */
+
+/* Data bitrate registers */
+#define RCANFD_F_CDFG(m)		(0x0500 + (0x20 * (m)))
+#define RCANFD_F_CFDCFG(m)		(0x0504 + (0x20 * (m)))
+#define RCANFD_F_CFDCTR(m)		(0x0508 + (0x20 * (m)))
+#define RCANFD_F_CFDSTS(m)		(0x050c + (0x20 * (m)))
+#define RCANFD_F_CFDCRC(m)		(0x0510 + (0x20 * (m)))
+
+#define RCANFD_F_GAFL_OFFSET		(0x1000)
+
+#define RCANFD_F_RMID(q)		(0x2000 + (0x10 * (q)))
+#define RCANFD_F_RMPTR(q)		(0x2004 + (0x10 * (q)))
+#define RCANFD_F_RMFDSTS(q)		(0x2008 + (0x10 * (q)))
+#define RCANFD_F_RMDF(q, b)		(0x200c + (0x04 * (b)) + (0x20 * (q)))
+
+/* Rx FIFO data registers */
+#define RCANFD_F_RFOFFSET		(0x3000)
+#define RCANFD_F_RFID(x)		(RCANFD_F_RFOFFSET + (0x80 * (x)))
+#define RCANFD_F_RFPTR(x)		(RCANFD_F_RFOFFSET + 0x04 + \
+					 (0x80 * (x)))
+#define RCANFD_F_RFFDSTS(x)		(RCANFD_F_RFOFFSET + 0x08 + \
+					 (0x80 * (x)))
+#define RCANFD_F_RFDF(x, df)		(RCANFD_F_RFOFFSET + 0x0c + \
+					 (0x80 * (x)) + (0x04 * (df)))
+
+/* Common FIFO data registers */
+#define RCANFD_F_CFOFFSET		(0x3400)
+#define RCANFD_F_CFID(ch, idx)		(RCANFD_F_CFOFFSET + (0x180 * (ch)) + \
+					 (0x80 * (idx)))
+#define RCANFD_F_CFPTR(ch, idx)		(RCANFD_F_CFOFFSET + 0x04 + \
+					 (0x180 * (ch)) + (0x80 * (idx)))
+#define RCANFD_F_CFFDCSTS(ch, idx)	(RCANFD_F_CFOFFSET + 0x08 + \
+					 (0x180 * (ch)) + (0x80 * (idx)))
+#define RCANFD_F_CFDF(ch, idx, df)	(RCANFD_F_CFOFFSET + 0x0c + \
+					 (0x180 * (ch)) + (0x80 * (idx)) + \
+					 (0x04 * (df)))
+
+#define RCANFD_F_TMID(p)		(0x4000 + (0x20 * (p)))
+#define RCANFD_F_TMPTR(p)		(0x4004 + (0x20 * (p)))
+#define RCANFD_F_TMFDCTR(p)		(0x4008 + (0x20 * (p)))
+#define RCANFD_F_TMDF(p, b)		(0x400c + (0x20 * (p)) + (0x04 * (b)))
+
+#define RCANFD_F_THLACC(m)		(0x6000 + (0x04 * (m)))
+#define RCANFD_F_RPGACC(r)		(0x6400 + (0x04 * (r)))
+
+struct rcar_canfd_global;
+
+/* Channel priv data */
+struct rcar_canfd_channel {
+	struct can_priv can;			/* Must be the first member */
+	struct net_device *ndev;
+	struct rcar_canfd_global *gpriv;	/* Controller reference */
+	void __iomem *base;			/* Register base address */
+#ifdef CONFIG_DEBUG_FS
+	struct dentry *dev_root;
+#endif /* CONFIG_DEBUG_FS */
+	struct napi_struct napi;
+	u8  tx_len[RCANFD_FIFO_DEPTH];		/* For net stats */
+	u32 tx_head;				/* Incremented on xmit */
+	u32 tx_tail;				/* Incremented on xmit done */
+	u32 channel;				/* Channel number */
+};
+
+/* Global priv data */
+struct rcar_canfd_global {
+	struct rcar_canfd_channel *ch[RCANFD_NUM_CHANNELS];
+	void __iomem *base;		/* Register base address */
+	struct platform_device *pdev;	/* Respective platform device */
+	struct clk *clkp;		/* Peripheral clock */
+	struct clk *can_clk;		/* fCAN clock */
+	int clock_select;		/* CANFD or Ext clock */
+	unsigned long channels_mask;	/* Enabled channels mask */
+	u32 freq;			/* fCAN clock frequency in Hz */
+};
+
+/* CAN FD mode nominal rate constants */
+static const struct can_bittiming_const rcar_canfd_nom_bittiming_const = {
+	.name = RCANFD_DRV_NAME,
+	.tseg1_min = 2,
+	.tseg1_max = 128,
+	.tseg2_min = 2,
+	.tseg2_max = 32,
+	.sjw_max = 32,
+	.brp_min = 1,
+	.brp_max = 1024,
+	.brp_inc = 1,
+};
+
+/* CAN FD mode data rate constants */
+static const struct can_bittiming_const rcar_canfd_data_bittiming_const = {
+	.name = RCANFD_DRV_NAME,
+	.tseg1_min = 2,
+	.tseg1_max = 16,
+	.tseg2_min = 2,
+	.tseg2_max = 8,
+	.sjw_max = 8,
+	.brp_min = 1,
+	.brp_max = 256,
+	.brp_inc = 1,
+};
+
+/* Test modes */
+enum {
+	RCANFD_TESTMODE_NONE = 0,
+	RCANFD_TESTMODE_INTERNAL_LOOPBACK,
+	RCANFD_TESTMODE_INTERCHANNEL,
+};
+
+static int testmode = RCANFD_TESTMODE_NONE;
+module_param(testmode, int, 0644);
+
+/* fCAN clock select register settings */
+enum {
+	RCANFD_CANFDCLK = 0,	/* CANFD clock */
+	RCANFD_EXTCLK,		/* Externally input clock */
+};
+
+/* Helper functions */
+static inline void rcar_canfd_update(u32 mask, u32 val, u32 __iomem *reg)
+{
+	u32 data = readl(reg);
+
+	data &= ~mask;
+	data |= (val & mask);
+	writel(data, reg);
+}
+
+#define rcar_canfd_read(priv, offset)			\
+	readl(priv->base + (offset))
+#define rcar_canfd_write(priv, offset, val)		\
+	writel(val, priv->base + (offset))
+#define rcar_canfd_set_bit(priv, reg, val)		\
+	rcar_canfd_update(val, val, priv->base + (reg))
+#define rcar_canfd_clear_bit(priv, reg, val)		\
+	rcar_canfd_update(val, 0, priv->base + (reg))
+#define rcar_canfd_update_bit(priv, reg, mask, val)	\
+	rcar_canfd_update(mask, val, priv->base + (reg))
+
+static void rcar_canfd_get_data(struct canfd_frame *cf,
+				struct rcar_canfd_channel *priv, u32 off)
+{
+	u32 i, lwords;
+
+	lwords = cf->len / sizeof(u32);
+	if (cf->len % sizeof(u32))
+		lwords++;
+	for (i = 0; i < lwords; i++)
+		*((u32 *)cf->data + i) =
+			rcar_canfd_read(priv, off + (i * sizeof(u32)));
+}
+
+static void rcar_canfd_put_data(struct canfd_frame *cf,
+				struct rcar_canfd_channel *priv, u32 off)
+{
+	u32 i, j, lwords, leftover;
+	u32 data = 0;
+
+	lwords = cf->len / sizeof(u32);
+	leftover = cf->len % sizeof(u32);
+	for (i = 0; i < lwords; i++)
+		rcar_canfd_write(priv, off + (i * sizeof(u32)),
+				 *((u32 *)cf->data + i));
+
+	if (leftover) {
+		u8 *p = (u8 *)((u32 *)cf->data + i);
+
+		for (j = 0; j < leftover; j++)
+			data |= p[j] << (j * 8);
+		rcar_canfd_write(priv, off + (i * sizeof(u32)), data);
+	}
+}
+
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+static int rcar_canfd_showregs(struct seq_file *s, void *data)
+{
+	struct rcar_canfd_channel *priv = s->private;
+	u32 ch = priv->channel;
+	u32 rf = ch + RCANFD_RFFIFO_IDX;
+	u32 cf = RCANFD_CFFIFO_IDX;
+	u32 val, offset, i;
+
+	if (testmode)
+		seq_printf(s, "RCANFD : testmode = %d\n", testmode);
+	seq_printf(s, "RCANFD register dump: channel %u\n", ch);
+	seq_printf(s, "%-40s: %x\n", "g: cfg",
+		   rcar_canfd_read(priv, RCANFD_GCFG));
+	seq_printf(s, "%-40s: %x\n", "g: ctr",
+		   rcar_canfd_read(priv, RCANFD_GCTR));
+	seq_printf(s, "%-40s: %x\n", "g: sts",
+		   rcar_canfd_read(priv, RCANFD_GSTS));
+	seq_printf(s, "%-40s: %x\n", "afl: ectr",
+		   rcar_canfd_read(priv, RCANFD_GAFLECTR));
+	seq_printf(s, "%-40s: %x\n", "afl: cfg0",
+		   rcar_canfd_read(priv, RCANFD_GAFLCFG0));
+	seq_printf(s, "%-40s: %x\n", "afl: cfg1",
+		   rcar_canfd_read(priv, RCANFD_GAFLCFG1));
+
+	offset = RCANFD_F_GAFL_OFFSET;
+	val = rcar_canfd_read(priv, RCANFD_GAFLCFG0);
+	if (ch == 0) /* Channel */
+		i = 0;	/* Start with 0th rule always */
+	else
+		i = RCANFD_AFLCFG_GETRNC0(val);
+
+	seq_printf(s, "%-40s: %x\n", "afl: id",
+		   rcar_canfd_read(priv, RCANFD_GAFLID(offset, i)));
+	seq_printf(s, "%-40s: %x\n", "afl: mask",
+		   rcar_canfd_read(priv, RCANFD_GAFLM(offset, i)));
+	seq_printf(s, "%-40s: %x\n", "afl: ptr0",
+		   rcar_canfd_read(priv, RCANFD_GAFLP0(offset, i)));
+	seq_printf(s, "%-40s: %x\n", "afl: ptr1",
+		   rcar_canfd_read(priv, RCANFD_GAFLP1(offset, i)));
+
+	seq_puts(s, "RCANFD Global and Channel error flags:\n");
+	val = rcar_canfd_read(priv, RCANFD_GERFL);
+	seq_printf(s, "%-40s: %x\n", "g: erfl", val);
+	if (val & RCANFD_GERFL_DEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "dlc error");
+	if (val & RCANFD_GERFL_MES)
+		seq_printf(s, "%-40s: %s\n", " --> ", "fifo msg lost");
+	if (val & RCANFD_GERFL_THLES)
+		seq_printf(s, "%-40s: %s\n", " --> ", "tx history lost");
+	if (val & RCANFD_GERFL_CMPOF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "payload overflow");
+	if (val & RCANFD_GERFL_EEF0)
+		seq_printf(s, "%-40s: %s\n", " --> ", "ecc ch0 error");
+	if (val & RCANFD_GERFL_EEF1)
+		seq_printf(s, "%-40s: %s\n", " --> ", "ecc ch1 error");
+	val = rcar_canfd_read(priv, RCANFD_CERFL(ch));
+	seq_printf(s, "%-40s: %x\n", "nr: erfl", val);
+	if (val & RCANFD_CERFL_ADEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "ack delimiter error");
+	if (val & RCANFD_CERFL_B0EF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "dominant bit error");
+	if (val & RCANFD_CERFL_B1EF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "recessive bit error");
+	if (val & RCANFD_CERFL_CEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "crc error");
+	if (val & RCANFD_CERFL_AEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "ack error");
+	if (val & RCANFD_CERFL_FEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "form error");
+	if (val & RCANFD_CERFL_SEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "stuff error");
+	if (val & RCANFD_CERFL_ALEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "arb lost");
+	if (val & RCANFD_CERFL_BLEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "bus lock");
+	if (val & RCANFD_CERFL_OLEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "overload");
+	if (val & RCANFD_CERFL_BOREF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "bus off recov");
+	if (val & RCANFD_CERFL_BOEEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "bus off entry");
+	if (val & RCANFD_CERFL_EPEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "error passive");
+	if (val & RCANFD_CERFL_EWEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "error warning");
+	if (val & RCANFD_CERFL_BEF)
+		seq_printf(s, "%-40s: %s\n", " --> ", "bus error");
+	seq_puts(s, "RCANFD Normal Control & Status Register:\n");
+	seq_printf(s, "%-40s: %x\n", "nr: ncfg",
+		   rcar_canfd_read(priv, RCANFD_CCFG(ch)));
+	seq_printf(s, "%-40s: %x\n", "nr: ctr",
+		   rcar_canfd_read(priv, RCANFD_CCTR(ch)));
+	val = rcar_canfd_read(priv, RCANFD_CSTS(ch));
+	seq_printf(s, "%-40s: %x\n", "nr: sts", val);
+	if (RCANFD_CSTS_TECCNT(val))
+		seq_printf(s, "%-40s: %x\n", " teccnt ",
+			   RCANFD_CSTS_TECCNT(val));
+	if (RCANFD_CSTS_RECCNT(val))
+		seq_printf(s, "%-40s: %x\n", " reccnt ",
+			   RCANFD_CSTS_RECCNT(val));
+	if (val & RCANFD_CSTS_BO)
+		seq_printf(s, "%-40s: %s\n", " --> ", "bus off status");
+	if (val & RCANFD_CSTS_EP)
+		seq_printf(s, "%-40s: %s\n", " --> ", "error passive status");
+	seq_puts(s, "RCANFD Data Status Register:\n");
+	seq_printf(s, "%-40s: %x\n", "dr: dcfg",
+		   rcar_canfd_read(priv, RCANFD_F_CDFG(ch)));
+	seq_printf(s, "%-40s: %x\n", "dr: fdcfg",
+		   rcar_canfd_read(priv, RCANFD_F_CFDCFG(ch)));
+	seq_printf(s, "%-40s: %x\n", "dr: fdctr",
+		   rcar_canfd_read(priv, RCANFD_F_CFDCTR(ch)));
+	val = rcar_canfd_read(priv, RCANFD_F_CFDSTS(ch));
+	seq_printf(s, "%-40s: %x\n", "dr: sts", val);
+	if (RCANFD_DCSTS_TDCR(val))
+		seq_printf(s, "%-40s: %x\n", " tdcr ",
+			   RCANFD_DCSTS_TDCR(val));
+	if (RCANFD_DCSTS_SOCCNT(val))
+		seq_printf(s, "%-40s: %x\n", " soccnt ",
+			   RCANFD_DCSTS_SOCCNT(val));
+	if (RCANFD_DCSTS_EOCCNT(val))
+		seq_printf(s, "%-40s: %x\n", " eoccnt ",
+			   RCANFD_DCSTS_EOCCNT(val));
+	if (val & RCANFD_DCSTS_EOCO)
+		seq_printf(s, "%-40s: %s\n", " --> ",
+			   "error occurrence overflow");
+	if (val & RCANFD_DCSTS_TDCVF)
+		seq_printf(s, "%-40s: %s\n", " --> ",
+			   "transmit delay correction violation");
+	seq_puts(s, "RCANFD FIFO Registers:\n");
+	seq_printf(s, "%-40s: %x\n", "rxfc: cc",
+		   rcar_canfd_read(priv, RCANFD_RFCC(rf)));
+	seq_printf(s, "%-40s: %x\n", "rxfc: bsts",
+		   rcar_canfd_read(priv, RCANFD_RFSTS(rf)));
+	seq_printf(s, "%-40s: %x\n", "rxfc: pctr",
+		   rcar_canfd_read(priv, RCANFD_RFPCTR(rf)));
+	seq_printf(s, "%-40s: %x\n", "rxfifo: sts",
+		   rcar_canfd_read(priv, RCANFD_F_RFFDSTS(rf)));
+	seq_printf(s, "%-40s: %x\n", "cmfc: cc",
+		   rcar_canfd_read(priv, RCANFD_CFCC(ch, cf)));
+	seq_printf(s, "%-40s: %x\n", "cmfc: bsts",
+		   rcar_canfd_read(priv, RCANFD_CFSTS(ch, cf)));
+	seq_printf(s, "%-40s: %x\n", "cmfc: pctr",
+		   rcar_canfd_read(priv, RCANFD_CFPCTR(ch, cf)));
+	seq_printf(s, "%-40s: %x\n", "cmfifo: sts",
+		   rcar_canfd_read(priv, RCANFD_F_CFFDCSTS(ch, cf)));
+	seq_printf(s, "%-40s: %x\n", "gtxintsts0",
+		   rcar_canfd_read(priv, RCANFD_GTINTSTS0));
+
+	seq_puts(s, "done\n");
+	return 0;
+}
+
+static int rcar_canfd_regs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, rcar_canfd_showregs, inode->i_private);
+}
+
+static const struct file_operations rcar_canfd_regs_ops = {
+	.open = rcar_canfd_regs_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+void rcar_canfd_init_debugfs(struct rcar_canfd_channel *priv)
+{
+	struct dentry *dev_root;
+	struct net_device *ndev = priv->ndev;
+
+	dev_root = debugfs_create_dir(dev_name(&ndev->dev), NULL);
+	priv->dev_root = dev_root;
+
+	if (IS_ERR(dev_root) || !dev_root) {
+		netdev_warn(ndev,
+			    "failed to create debugfs dir for %s (ch %u)\n",
+			    dev_name(&ndev->dev), priv->channel);
+		return;
+	}
+	debugfs_create_file("dumpregs", S_IFREG | S_IRUGO, dev_root, priv,
+			    &rcar_canfd_regs_ops);
+}
+
+void rcar_canfd_remove_debugfs(struct rcar_canfd_channel *priv)
+{
+	debugfs_remove_recursive(priv->dev_root);
+}
+#else
+void rcar_canfd_init_debugfs(struct rcar_canfd_channel *priv)
+{
+}
+
+void rcar_canfd_remove_debugfs(struct rcar_canfd_channel *priv)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
+static void rcar_canfd_tx_failure_cleanup(struct net_device *ndev)
+{
+	u32 i;
+
+	for (i = 0; i < RCANFD_FIFO_DEPTH; i++)
+		can_free_echo_skb(ndev, i);
+}
+
+static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv)
+{
+	u32 sts, ch;
+	int err;
+
+	/* Check RAMINIT flag as CAN RAM initialization takes place
+	 * after the MCU reset
+	 */
+	err = readl_poll_timeout((gpriv->base + RCANFD_GSTS), sts,
+				 !(sts & RCANFD_GSTS_RAMINIT), 2, 500000);
+	if (err) {
+		dev_dbg(&gpriv->pdev->dev, "global raminit failed\n");
+		return err;
+	}
+
+	/* Transition to Global Reset mode */
+	rcar_canfd_clear_bit(gpriv, RCANFD_GCTR, RCANFD_GCTR_SLPR);
+	rcar_canfd_update_bit(gpriv, RCANFD_GCTR,
+			      RCANFD_GCTR_MODEMASK, RCANFD_GCTR_GRESET);
+
+	/* Ensure Global reset mode */
+	err = readl_poll_timeout((gpriv->base + RCANFD_GSTS), sts,
+				 (sts & RCANFD_GSTS_RESET), 2, 500000);
+	if (err) {
+		dev_dbg(&gpriv->pdev->dev, "global reset failed\n");
+		return err;
+	}
+
+	/* Reset Global error flags */
+	rcar_canfd_write(gpriv, RCANFD_GERFL, 0x0);
+
+	/* Set the controller into FD mode */
+	rcar_canfd_set_bit(gpriv, RCANFD_GRMCFG, RCANFD_GINTF_CANFD);
+
+	/* Transition all Channels to reset mode */
+	for_each_set_bit(ch, &gpriv->channels_mask, RCANFD_NUM_CHANNELS) {
+		rcar_canfd_clear_bit(gpriv, RCANFD_CCTR(ch), RCANFD_CCTR_CSLPR);
+
+		rcar_canfd_update_bit(gpriv, RCANFD_CCTR(ch),
+				      RCANFD_CCTR_MODEMASK,
+				      RCANFD_CCTR_CRESET);
+
+		/* Ensure Channel reset mode */
+		err = readl_poll_timeout((gpriv->base + RCANFD_CSTS(ch)), sts,
+					 (sts & RCANFD_CSTS_RESET), 2, 500000);
+		if (err) {
+			dev_dbg(&gpriv->pdev->dev,
+				"channel %u reset failed\n", ch);
+			return err;
+		}
+	}
+	return 0;
+}
+
+static void rcar_canfd_configure_controller(struct rcar_canfd_global *gpriv)
+{
+	u32 cfg, ch;
+
+	/* Global Configuration settings */
+	cfg = RCANFD_GCFG_EEFE;		/* ECC error flag enabled */
+
+	/* Set External Clock if selected */
+	if (gpriv->clock_select != RCANFD_CANFDCLK)
+		cfg |= RCANFD_GCFG_DCS;
+
+	/* Truncate payload to configured message size RFPLS */
+	cfg |= RCANFD_GCFG_CMPOC;
+
+	rcar_canfd_set_bit(gpriv, RCANFD_GCFG, cfg);
+
+	/* Channel configuration settings */
+	for_each_set_bit(ch, &gpriv->channels_mask, RCANFD_NUM_CHANNELS) {
+		rcar_canfd_set_bit(gpriv, RCANFD_CCTR(ch), RCANFD_CCTR_ERRD);
+		rcar_canfd_update_bit(gpriv, RCANFD_CCTR(ch),
+				      RCANFD_CCTR_BOMMASK,
+				      RCANFD_CCTR_BOM_ENTRY);
+	}
+}
+
+static int rcar_canfd_configure_selftest_mode(struct rcar_canfd_channel *priv)
+{
+	u32 sts, err;
+	u32 ch = priv->channel;
+
+	rcar_canfd_update_bit(priv, RCANFD_CCTR(ch),
+			      RCANFD_CCTR_MODEMASK, RCANFD_CCTR_CHLT);
+
+	/* Verify channel mode change */
+	err = readl_poll_timeout((priv->base + RCANFD_CSTS(ch)), sts,
+				 (sts & RCANFD_CSTS_HALT), 2, 500000);
+	if (err) {
+		netdev_dbg(priv->ndev, "channel halt failed\n");
+		return err;
+	}
+
+	/* Internal Selt Test mode */
+	rcar_canfd_update_bit(priv, RCANFD_CCTR(ch), RCANFD_CCTR_CTMASK,
+			      RCANFD_CCTR_CTMS_ILB);
+	rcar_canfd_set_bit(priv, RCANFD_CCTR(ch), RCANFD_CCTR_CTME);
+	return 0;
+}
+
+static int rcar_canfd_configure_interch_mode(struct rcar_canfd_global *gpriv)
+{
+	u32 sts;
+	int err;
+
+	rcar_canfd_update_bit(gpriv, RCANFD_GCTR,
+			      RCANFD_GCTR_MODEMASK, RCANFD_GCTR_GHLT);
+
+	/* Ensure Global Halt mode */
+	err = readl_poll_timeout((gpriv->base + RCANFD_GSTS), sts,
+				 (sts & RCANFD_GSTS_HLT), 2, 500000);
+	if (err) {
+		dev_dbg(&gpriv->pdev->dev, "global halt mode failed\n");
+		return err;
+	}
+
+	rcar_canfd_set_bit(gpriv, RCANFD_GTSTCFG,
+			   (RCANFD_GTSTCFG_C0CBCE | RCANFD_GTSTCFG_C1CBCE));
+	rcar_canfd_set_bit(gpriv, RCANFD_GTSTCTR, RCANFD_GTSTCTR_ICBCTME);
+
+	/* Verify inter-channel mode enabled */
+	err = readl_poll_timeout((gpriv->base + RCANFD_GTSTCTR), sts,
+				 (sts & RCANFD_GTSTCTR_ICBCTME), 2, 500000);
+	if (err) {
+		dev_dbg(&gpriv->pdev->dev,
+			"global inter-channel test mode failed\n");
+		return err;
+	}
+	return 0;
+}
+
+static void rcar_canfd_configure_afl_rules(struct rcar_canfd_global *gpriv,
+					   u32 ch)
+{
+	u32 cfg;
+	int start, page, num_rules = RCANFD_CHANNEL_NUMRULES;
+	u32 ridx = ch + RCANFD_RFFIFO_IDX;
+
+	if (ch == 0) {
+		start = 0; /* Start from 0th rule */
+	} else {
+		/* Get number of existing rules and adjust */
+		cfg = rcar_canfd_read(gpriv, RCANFD_GAFLCFG0);
+		start = RCANFD_AFLCFG_GETRNC0(cfg);
+	}
+
+	/* Enable write access to entry */
+	page = RCANFD_AFL_PAGENUM(start);
+	rcar_canfd_set_bit(gpriv, RCANFD_GAFLECTR,
+			   (RCANFD_AFLCTR_AFLPN(page) | RCANFD_AFLCTR_AFLDAE));
+
+	/* Write number of rules for channel */
+	if (ch == 0)
+		rcar_canfd_set_bit(gpriv, RCANFD_GAFLCFG0,
+				   RCANFD_AFLCFG_SETRNC0(num_rules));
+	else
+		rcar_canfd_set_bit(gpriv, RCANFD_GAFLCFG0,
+				   RCANFD_AFLCFG_SETRNC1(num_rules));
+
+	/* Set the rule of that page */
+	if (testmode == RCANFD_TESTMODE_INTERNAL_LOOPBACK)
+		rcar_canfd_write(gpriv,
+				 RCANFD_GAFLID(RCANFD_F_GAFL_OFFSET, start),
+				 RCANFD_AFLID_GAFLLB);
+	else
+		/* Accept all IDs */
+		rcar_canfd_write(gpriv,
+				 RCANFD_GAFLID(RCANFD_F_GAFL_OFFSET, start), 0);
+
+	/* IDE or RTR is not considered for matching */
+	rcar_canfd_write(gpriv, RCANFD_GAFLM(RCANFD_F_GAFL_OFFSET, start), 0);
+	/* Any data length accepted */
+	rcar_canfd_write(gpriv, RCANFD_GAFLP0(RCANFD_F_GAFL_OFFSET, start), 0);
+	/* Place the msg in corresponding Rx FIFO entry */
+	rcar_canfd_write(gpriv, RCANFD_GAFLP1(RCANFD_F_GAFL_OFFSET, start),
+			 RCANFD_AFLPTR1_RFFIFO(ridx));
+
+	/* Disable write access to page */
+	rcar_canfd_clear_bit(gpriv, RCANFD_GAFLECTR, RCANFD_AFLCTR_AFLDAE);
+}
+
+static void rcar_canfd_configure_rx(struct rcar_canfd_global *gpriv, u32 ch)
+{
+	/* Rx FIFO is used for reception */
+	u32 cfg;
+	u16 rfdc, rfpls;
+
+	/* Select Rx FIFO based on channel */
+	u32 ridx = ch + RCANFD_RFFIFO_IDX;
+
+	rfdc = 2;		/* b010 - 8 messages Rx FIFO depth */
+	rfpls = 7;		/* b111 - Max 64 bytes payload */
+
+	cfg = (RCANFD_RFFIFO_RFIM | RCANFD_RFFIFO_RFDC(rfdc) |
+		RCANFD_RFFIFO_RFPLS(rfpls) | RCANFD_RFFIFO_RFIE);
+	rcar_canfd_write(gpriv, RCANFD_RFCC(ridx), cfg);
+}
+
+static void rcar_canfd_configure_tx(struct rcar_canfd_global *gpriv, u32 ch)
+{
+	/* Tx/Rx(Common) FIFO configured in Tx mode is
+	 * used for transmission
+	 *
+	 * Each channel has 3 Common FIFO dedicated to them.
+	 * Use the 1st (index 0) out of 3
+	 */
+	u32 cfg;
+	u16 cftml, cfm, cfdc, cfpls;
+
+	cftml = 0;		/* 0th buffer */
+	cfm = 1;		/* b01 - Transmit mode */
+	cfdc = 2;		/* b010 - 8 messages Tx FIFO depth */
+	cfpls = 7;		/* b111 - Max 64 bytes payload */
+
+	cfg = (RCANFD_CMFIFO_TML(cftml) | RCANFD_CMFIFO_M(cfm) |
+		RCANFD_CMFIFO_CFIM | RCANFD_CMFIFO_DC(cfdc) |
+		RCANFD_CMFIFO_PLS(cfpls) | RCANFD_CMFIFO_CFTXIE);
+	rcar_canfd_write(gpriv, RCANFD_CFCC(ch, RCANFD_CFFIFO_IDX), cfg);
+
+	/* Clear FD mode specific control/status register */
+	rcar_canfd_write(gpriv, RCANFD_F_CFFDCSTS(ch, RCANFD_CFFIFO_IDX), 0);
+}
+
+static void rcar_canfd_enable_global_interrupts(struct rcar_canfd_global *gpriv)
+{
+	u32 ctr;
+
+	/* Clear any stray error interrupt flags */
+	rcar_canfd_write(gpriv, RCANFD_GERFL, 0);
+
+	/* Global interrupts setup */
+	ctr = RCANFD_GCTR_MEIE;
+	ctr |= RCANFD_GCTR_CFMPOFIE;
+
+	rcar_canfd_set_bit(gpriv, RCANFD_GCTR, ctr);
+}
+
+static void rcar_canfd_disable_global_interrupts(struct rcar_canfd_global
+						 *gpriv)
+{
+	/* Disable all interrupts */
+	rcar_canfd_write(gpriv, RCANFD_GCTR, 0);
+
+	/* Clear any stray error interrupt flags */
+	rcar_canfd_write(gpriv, RCANFD_GERFL, 0);
+}
+
+static void rcar_canfd_enable_channel_interrupts(struct rcar_canfd_channel
+						 *priv)
+{
+	u32 ctr, ch = priv->channel;
+
+	/* Clear any stray error flags */
+	rcar_canfd_write(priv, RCANFD_CERFL(ch), 0);
+
+	/* Channel interrupts setup */
+	ctr = (RCANFD_CCTR_TAIE |
+	       RCANFD_CCTR_ALIE | RCANFD_CCTR_BLIE |
+	       RCANFD_CCTR_OLIE | RCANFD_CCTR_BORIE |
+	       RCANFD_CCTR_BOEIE | RCANFD_CCTR_EPIE |
+	       RCANFD_CCTR_EWIE | RCANFD_CCTR_BEIE);
+	rcar_canfd_set_bit(priv, RCANFD_CCTR(ch), ctr);
+}
+
+static void rcar_canfd_disable_channel_interrupts(struct rcar_canfd_channel
+						  *priv)
+{
+	u32 ctr, ch = priv->channel;
+
+	ctr = (RCANFD_CCTR_TAIE |
+	       RCANFD_CCTR_ALIE | RCANFD_CCTR_BLIE |
+	       RCANFD_CCTR_OLIE | RCANFD_CCTR_BORIE |
+	       RCANFD_CCTR_BOEIE | RCANFD_CCTR_EPIE |
+	       RCANFD_CCTR_EWIE | RCANFD_CCTR_BEIE);
+	rcar_canfd_clear_bit(priv, RCANFD_CCTR(ch), ctr);
+
+	/* Clear any stray error flags */
+	rcar_canfd_write(priv, RCANFD_CERFL(ch), 0);
+}
+
+static void rcar_canfd_global_error(struct net_device *ndev)
+{
+	struct rcar_canfd_channel *priv = netdev_priv(ndev);
+	struct net_device_stats *stats = &ndev->stats;
+	u32 ch = priv->channel;
+	u32 gerfl, sts;
+	u32 ridx = ch + RCANFD_RFFIFO_IDX;
+
+	gerfl = rcar_canfd_read(priv, RCANFD_GERFL);
+	if ((gerfl & RCANFD_GERFL_EEF0) && (ch == 0)) {
+		netdev_dbg(ndev, "Ch0: ECC Error flag\n");
+		stats->tx_dropped++;
+	}
+	if ((gerfl & RCANFD_GERFL_EEF1) && (ch == 1)) {
+		netdev_dbg(ndev, "Ch1: ECC Error flag\n");
+		stats->tx_dropped++;
+	}
+	if (gerfl & RCANFD_GERFL_MES) {
+		sts = rcar_canfd_read(priv,
+				      RCANFD_CFSTS(ch, RCANFD_CFFIFO_IDX));
+		if (sts & RCANFD_CMFIFO_CFMLT) {
+			netdev_dbg(ndev, "Tx Message Lost flag\n");
+			stats->tx_dropped++;
+			rcar_canfd_write(priv,
+					 RCANFD_CFSTS(ch, RCANFD_CFFIFO_IDX),
+					 sts & ~RCANFD_CMFIFO_CFMLT);
+		}
+
+		sts = rcar_canfd_read(priv, RCANFD_RFSTS(ridx));
+		if (sts & RCANFD_RFFIFO_RFMLT) {
+			netdev_dbg(ndev, "Rx Message Lost flag\n");
+			stats->rx_dropped++;
+			rcar_canfd_write(priv, RCANFD_RFSTS(ridx),
+					 sts & ~RCANFD_RFFIFO_RFMLT);
+		}
+	}
+	if (gerfl & RCANFD_GERFL_CMPOF) {
+		/* Message Lost flag will be set for respective channel
+		 * when this condition happens with counters and flags
+		 * already updated.
+		 */
+		netdev_dbg(ndev, "global payload overflow interrupt\n");
+	}
+
+	/* Clear all global error interrupts. Only affected channels bits
+	 * get cleared
+	 */
+	rcar_canfd_write(priv, RCANFD_GERFL, 0);
+}
+
+static void rcar_canfd_error(struct net_device *ndev)
+{
+	struct rcar_canfd_channel *priv = netdev_priv(ndev);
+	struct net_device_stats *stats = &ndev->stats;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+	u32 cerfl, csts;
+	u32 txerr = 0, rxerr = 0;
+	u32 ch = priv->channel;
+
+	/* Propagate the error condition to the CAN stack */
+	skb = alloc_can_err_skb(ndev, &cf);
+	if (!skb) {
+		stats->rx_dropped++;
+		return;
+	}
+
+	/* Channel error interrupt */
+	cerfl = rcar_canfd_read(priv, RCANFD_CERFL(ch));
+	csts = rcar_canfd_read(priv, RCANFD_CSTS(ch));
+	txerr = RCANFD_CSTS_TECCNT(csts);
+	rxerr = RCANFD_CSTS_RECCNT(csts);
+
+	netdev_dbg(ndev, "ch erfl %x sts %x txerr %u rxerr %u\n",
+		   cerfl, csts, txerr, rxerr);
+
+	if (cerfl & RCANFD_CERFL_BEF) {
+		netdev_dbg(ndev, "Bus error\n");
+		cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_PROT;
+		cf->data[2] = CAN_ERR_PROT_UNSPEC;
+		priv->can.can_stats.bus_error++;
+	}
+	if (cerfl & RCANFD_CERFL_ADEF) {
+		netdev_dbg(ndev, "ACK Delimiter Error\n");
+		stats->tx_errors++;
+		cf->data[3] |= CAN_ERR_PROT_LOC_ACK_DEL;
+	}
+	if (cerfl & RCANFD_CERFL_B0EF) {
+		netdev_dbg(ndev, "Bit Error (dominant)\n");
+		stats->tx_errors++;
+		cf->data[2] |= CAN_ERR_PROT_BIT0;
+	}
+	if (cerfl & RCANFD_CERFL_B1EF) {
+		netdev_dbg(ndev, "Bit Error (recessive)\n");
+		stats->tx_errors++;
+		cf->data[2] |= CAN_ERR_PROT_BIT1;
+	}
+	if (cerfl & RCANFD_CERFL_CEF) {
+		netdev_dbg(ndev, "CRC Error\n");
+		stats->rx_errors++;
+		cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ;
+	}
+	if (cerfl & RCANFD_CERFL_AEF) {
+		netdev_dbg(ndev, "ACK Error\n");
+		stats->tx_errors++;
+		cf->can_id |= CAN_ERR_ACK;
+		cf->data[3] |= CAN_ERR_PROT_LOC_ACK;
+	}
+	if (cerfl & RCANFD_CERFL_FEF) {
+		netdev_dbg(ndev, "Form Error\n");
+		stats->rx_errors++;
+		cf->data[2] |= CAN_ERR_PROT_FORM;
+	}
+	if (cerfl & RCANFD_CERFL_SEF) {
+		netdev_dbg(ndev, "Stuff Error\n");
+		stats->rx_errors++;
+		cf->data[2] |= CAN_ERR_PROT_STUFF;
+	}
+	if (cerfl & RCANFD_CERFL_ALEF) {
+		netdev_dbg(ndev, "Arbitration lost Error\n");
+		priv->can.can_stats.arbitration_lost++;
+		cf->can_id |= CAN_ERR_LOSTARB;
+		cf->data[0] |= CAN_ERR_LOSTARB_UNSPEC;
+	}
+	if (cerfl & RCANFD_CERFL_BLEF) {
+		netdev_dbg(ndev, "Bus Lock Error\n");
+		stats->rx_errors++;
+		cf->can_id |= CAN_ERR_BUSERROR;
+	}
+	if (cerfl & RCANFD_CERFL_EWEF) {
+		netdev_dbg(ndev, "Error warning interrupt\n");
+		priv->can.state = CAN_STATE_ERROR_WARNING;
+		priv->can.can_stats.error_warning++;
+		cf->can_id |= CAN_ERR_CRTL;
+		cf->data[1] = txerr > rxerr ? CAN_ERR_CRTL_TX_WARNING :
+			CAN_ERR_CRTL_RX_WARNING;
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
+	}
+	if (cerfl & RCANFD_CERFL_EPEF) {
+		netdev_dbg(ndev, "Error passive interrupt\n");
+		priv->can.state = CAN_STATE_ERROR_PASSIVE;
+		priv->can.can_stats.error_passive++;
+		cf->can_id |= CAN_ERR_CRTL;
+		cf->data[1] = txerr > rxerr ? CAN_ERR_CRTL_TX_PASSIVE :
+			CAN_ERR_CRTL_RX_PASSIVE;
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
+	}
+	if (cerfl & RCANFD_CERFL_BOEEF) {
+		netdev_dbg(ndev, "Bus-off entry interrupt\n");
+		rcar_canfd_tx_failure_cleanup(ndev);
+		priv->can.state = CAN_STATE_BUS_OFF;
+		priv->can.can_stats.bus_off++;
+		can_bus_off(ndev);
+		cf->can_id |= CAN_ERR_BUSOFF;
+	}
+	if (cerfl & RCANFD_CERFL_OLEF) {
+		netdev_dbg(ndev,
+			   "Overload Frame Transmission error interrupt\n");
+		stats->tx_errors++;
+		cf->can_id |= CAN_ERR_PROT;
+		cf->data[2] |= CAN_ERR_PROT_OVERLOAD;
+	}
+
+	/* Clear all channel error interrupts */
+	rcar_canfd_write(priv, RCANFD_CERFL(ch), 0);
+	stats->rx_packets++;
+	stats->rx_bytes += cf->can_dlc;
+	netif_rx(skb);
+}
+
+static void rcar_canfd_tx_done(struct net_device *ndev)
+{
+	struct rcar_canfd_channel *priv = netdev_priv(ndev);
+	struct net_device_stats *stats = &ndev->stats;
+	u32 sts;
+	u32 ch = priv->channel;
+
+	while (1) {
+		u8 unsent;
+
+		sts = rcar_canfd_read(priv,
+				      RCANFD_CFSTS(ch, RCANFD_CFFIFO_IDX));
+		unsent = RCANFD_CMFIFO_CFMC(sts);
+
+		if (priv->tx_head - priv->tx_tail <= unsent)
+			break;
+
+		stats->tx_packets++;
+		stats->tx_bytes += priv->tx_len[priv->tx_tail %
+						RCANFD_FIFO_DEPTH];
+		priv->tx_len[priv->tx_tail % RCANFD_FIFO_DEPTH] = 0;
+		can_get_echo_skb(ndev, priv->tx_tail % RCANFD_FIFO_DEPTH);
+		priv->tx_tail++;
+		netif_wake_queue(ndev);
+	}
+
+	/* Clear interrupt */
+	rcar_canfd_write(priv, RCANFD_CFSTS(ch, RCANFD_CFFIFO_IDX),
+			 sts & ~RCANFD_CMFIFO_CFTXIF);
+	can_led_event(ndev, CAN_LED_EVENT_TX);
+}
+
+static irqreturn_t rcar_canfd_global_interrupt(int irq, void *dev_id)
+{
+	struct rcar_canfd_global *gpriv = dev_id;
+	struct net_device *ndev;
+	struct rcar_canfd_channel *priv;
+	u32 sts, gerfl;
+	u32 ch, ridx;
+
+	/* Global error interrupts still indicate a condition specific
+	 * to a channel. RxFIFO interrupt is a global interrupt.
+	 */
+	for_each_set_bit(ch, &gpriv->channels_mask, RCANFD_NUM_CHANNELS) {
+		priv = gpriv->ch[ch];
+		ndev = priv->ndev;
+		ridx = ch + RCANFD_RFFIFO_IDX;
+
+		/* Global error interrupts */
+		gerfl = rcar_canfd_read(priv, RCANFD_GERFL);
+		if (RCANFD_GERFL_ERR(gerfl))
+			rcar_canfd_global_error(ndev);
+
+		/* Handle Rx interrupts */
+		sts = rcar_canfd_read(priv, RCANFD_RFSTS(ridx));
+		if (sts & RCANFD_RFFIFO_RFIF) {
+			if (napi_schedule_prep(&priv->napi)) {
+				/* Disable Rx FIFO interrupts */
+				rcar_canfd_clear_bit(priv,
+						     RCANFD_RFCC(ridx),
+						     RCANFD_RFFIFO_RFIE);
+				__napi_schedule(&priv->napi);
+			}
+		}
+	}
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t rcar_canfd_channel_interrupt(int irq, void *dev_id)
+{
+	struct rcar_canfd_global *gpriv = dev_id;
+	struct net_device *ndev;
+	struct rcar_canfd_channel *priv;
+	u32 sts, cerfl, ch;
+
+	/* Common FIFO is a per channel resource */
+	for_each_set_bit(ch, &gpriv->channels_mask, RCANFD_NUM_CHANNELS) {
+		priv = gpriv->ch[ch];
+		ndev = priv->ndev;
+
+		/* Channel error interrupts */
+		cerfl = rcar_canfd_read(priv, RCANFD_CERFL(ch));
+		if (RCANFD_CERFL_ERR(cerfl))
+			rcar_canfd_error(ndev);
+
+		/* Handle Tx interrupts */
+		sts = rcar_canfd_read(priv,
+				      RCANFD_CFSTS(ch, RCANFD_CFFIFO_IDX));
+		if (sts & RCANFD_CMFIFO_CFTXIF)
+			rcar_canfd_tx_done(ndev);
+	}
+	return IRQ_HANDLED;
+}
+
+static void rcar_canfd_set_bittiming(struct net_device *dev)
+{
+	struct rcar_canfd_channel *priv = netdev_priv(dev);
+	const struct can_bittiming *bt = &priv->can.bittiming;
+	const struct can_bittiming *dbt = &priv->can.data_bittiming;
+	u16 brp, sjw, tseg1, tseg2;
+	u32 cfg;
+	u32 ch = priv->channel;
+
+	/* Nominal bit timing settings */
+	brp = bt->brp - 1;
+	sjw = bt->sjw - 1;
+	tseg1 = bt->prop_seg + bt->phase_seg1 - 1;
+	tseg2 = bt->phase_seg2 - 1;
+
+	cfg = (RCANFD_NR_TSEG1(tseg1) | RCANFD_NR_BRP(brp) |
+	       RCANFD_NR_SJW(sjw) | RCANFD_NR_TSEG2(tseg2));
+
+	rcar_canfd_write(priv, RCANFD_CCFG(ch), cfg);
+	netdev_dbg(priv->ndev, "nrate: brp %u, sjw %u, tseg1 %u, tseg2 %u\n",
+		   brp, sjw, tseg1, tseg2);
+
+	/* Data bit timing settings */
+	brp = dbt->brp - 1;
+	sjw = dbt->sjw - 1;
+	tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1;
+	tseg2 = dbt->phase_seg2 - 1;
+
+	cfg = (RCANFD_DR_TSEG1(tseg1) | RCANFD_DR_BRP(brp) |
+	       RCANFD_DR_SJW(sjw) | RCANFD_DR_TSEG2(tseg2));
+
+	rcar_canfd_write(priv, RCANFD_F_CDFG(ch), cfg);
+	netdev_dbg(priv->ndev, "drate: brp %u, sjw %u, tseg1 %u, tseg2 %u\n",
+		   brp, sjw, tseg1, tseg2);
+}
+
+static int rcar_canfd_start(struct net_device *ndev)
+{
+	struct rcar_canfd_channel *priv = netdev_priv(ndev);
+	int err = -EOPNOTSUPP;
+	u32 sts, ch = priv->channel;
+	u32 ridx = ch + RCANFD_RFFIFO_IDX;
+
+	/* Ensure channel starts in FD mode */
+	if (!(priv->can.ctrlmode & CAN_CTRLMODE_FD)) {
+		netdev_err(ndev, "enable can fd mode for channel %d\n", ch);
+		goto fail_mode;
+	}
+
+	rcar_canfd_set_bittiming(ndev);
+
+	rcar_canfd_enable_channel_interrupts(priv);
+
+	if (testmode == RCANFD_TESTMODE_INTERNAL_LOOPBACK) {
+		/* Enable self test mode */
+		err = rcar_canfd_configure_selftest_mode(priv);
+		if (err) {
+			netdev_err(ndev,
+				   "channel %u self-test mode failed\n", ch);
+			goto fail_mode_change;
+		}
+	}
+
+	/* Set channel to Operational mode */
+	rcar_canfd_update_bit(priv, RCANFD_CCTR(ch),
+			      RCANFD_CCTR_MODEMASK, RCANFD_CCTR_COPM);
+
+	/* Verify channel mode change */
+	err = readl_poll_timeout((priv->base + RCANFD_CSTS(ch)), sts,
+				 (sts & RCANFD_CSTS_COM), 2, 500000);
+	if (err) {
+		netdev_err(ndev, "channel %u communication state failed\n", ch);
+		goto fail_mode_change;
+	}
+
+	/* Enable Common & Rx FIFO */
+	rcar_canfd_set_bit(priv, RCANFD_CFCC(ch, RCANFD_CFFIFO_IDX),
+			   RCANFD_CMFIFO_CFE);
+	rcar_canfd_set_bit(priv, RCANFD_RFCC(ridx), RCANFD_RFFIFO_RFE);
+
+	priv->can.state = CAN_STATE_ERROR_ACTIVE;
+	return 0;
+
+fail_mode_change:
+	rcar_canfd_disable_channel_interrupts(priv);
+fail_mode:
+	return err;
+}
+
+static int rcar_canfd_open(struct net_device *ndev)
+{
+	struct rcar_canfd_channel *priv = netdev_priv(ndev);
+	struct rcar_canfd_global *gpriv = priv->gpriv;
+	int err;
+
+	/* Peripheral clock is already enabled in probe */
+	err = clk_prepare_enable(gpriv->can_clk);
+	if (err) {
+		netdev_err(ndev, "failed to enable CAN clock, error %d\n", err);
+		goto out_clock;
+	}
+
+	err = open_candev(ndev);
+	if (err) {
+		netdev_err(ndev, "open_candev() failed, error %d\n", err);
+		goto out_can_clock;
+	}
+
+	napi_enable(&priv->napi);
+	err = rcar_canfd_start(ndev);
+	if (err)
+		goto out_close;
+	netif_start_queue(ndev);
+	can_led_event(ndev, CAN_LED_EVENT_OPEN);
+	return 0;
+out_close:
+	napi_disable(&priv->napi);
+	close_candev(ndev);
+out_can_clock:
+	clk_disable_unprepare(gpriv->can_clk);
+out_clock:
+	return err;
+}
+
+static void rcar_canfd_stop(struct net_device *ndev)
+{
+	struct rcar_canfd_channel *priv = netdev_priv(ndev);
+	int err;
+	u32 sts, ch = priv->channel;
+	u32 ridx = ch + RCANFD_RFFIFO_IDX;
+
+	/* Transition to channel reset mode  */
+	rcar_canfd_update_bit(priv, RCANFD_CCTR(ch),
+			      RCANFD_CCTR_MODEMASK, RCANFD_CCTR_CRESET);
+
+	/* Check Channel reset mode */
+	err = readl_poll_timeout((priv->base + RCANFD_CSTS(ch)), sts,
+				 (sts & RCANFD_CSTS_RESET), 2, 500000);
+	if (err)
+		netdev_err(ndev, "channel %u reset failed\n", ch);
+
+	rcar_canfd_disable_channel_interrupts(priv);
+
+	/* Disable Common & Rx FIFO */
+	rcar_canfd_clear_bit(priv, RCANFD_CFCC(ch, RCANFD_CFFIFO_IDX),
+			     RCANFD_CMFIFO_CFE);
+	rcar_canfd_clear_bit(priv, RCANFD_RFCC(ridx), RCANFD_RFFIFO_RFE);
+
+	/* Set the state as STOPPED */
+	priv->can.state = CAN_STATE_STOPPED;
+}
+
+static int rcar_canfd_close(struct net_device *ndev)
+{
+	struct rcar_canfd_channel *priv = netdev_priv(ndev);
+	struct rcar_canfd_global *gpriv = priv->gpriv;
+
+	netif_stop_queue(ndev);
+	rcar_canfd_stop(ndev);
+	napi_disable(&priv->napi);
+	clk_disable_unprepare(gpriv->can_clk);
+	close_candev(ndev);
+	can_led_event(ndev, CAN_LED_EVENT_STOP);
+	return 0;
+}
+
+static netdev_tx_t rcar_canfd_start_xmit(struct sk_buff *skb,
+					 struct net_device *ndev)
+{
+	struct rcar_canfd_channel *priv = netdev_priv(ndev);
+	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
+	u32 sts, id, ptr;
+	u32 ch = priv->channel;
+
+	if (can_dropped_invalid_skb(ndev, skb))
+		return NETDEV_TX_OK;
+
+	if (cf->can_id & CAN_EFF_FLAG) {
+		id = cf->can_id & CAN_EFF_MASK;
+		id |= RCANFD_CMFIFO_CFIDE;
+	} else {
+		id = cf->can_id & CAN_SFF_MASK;
+	}
+
+	if (cf->can_id & CAN_RTR_FLAG)
+		id |= RCANFD_CMFIFO_CFRTR;
+
+	rcar_canfd_write(priv, RCANFD_F_CFID(ch, RCANFD_CFFIFO_IDX),
+			 id);
+	ptr = RCANFD_CMFIFO_CFDLC(can_len2dlc(cf->len));
+	rcar_canfd_write(priv, RCANFD_F_CFPTR(ch, RCANFD_CFFIFO_IDX),
+			 ptr);
+
+	rcar_canfd_put_data(cf, priv,
+			    RCANFD_F_CFDF(ch, RCANFD_CFFIFO_IDX, 0));
+
+	priv->tx_len[priv->tx_head % RCANFD_FIFO_DEPTH] = cf->len;
+	can_put_echo_skb(skb, ndev, priv->tx_head % RCANFD_FIFO_DEPTH);
+	priv->tx_head++;
+
+	sts = rcar_canfd_read(priv, RCANFD_F_CFFDCSTS(ch, RCANFD_CFFIFO_IDX));
+	if (can_is_canfd_skb(skb)) {
+		/* CAN FD frame format */
+		sts |= RCANFD_CMFIFO_CFFDF;
+		if (cf->flags & CANFD_BRS)
+			sts |= RCANFD_CMFIFO_CFBRS;
+		else
+			sts &= ~RCANFD_CMFIFO_CFBRS;
+	} else {
+		sts &= ~RCANFD_CMFIFO_CFFDF;
+	}
+	rcar_canfd_write(priv, RCANFD_F_CFFDCSTS(ch, RCANFD_CFFIFO_IDX), sts);
+
+	/* Start Tx: Write 0xff to CFPC to increment the CPU-side
+	 * pointer for the Common FIFO
+	 */
+	rcar_canfd_write(priv, RCANFD_CFPCTR(ch, RCANFD_CFFIFO_IDX), 0xff);
+
+	/* Stop the queue if we've filled all FIFO entries */
+	if (priv->tx_head - priv->tx_tail >= RCANFD_FIFO_DEPTH)
+		netif_stop_queue(ndev);
+	return NETDEV_TX_OK;
+}
+
+static void rcar_canfd_rx_pkt(struct rcar_canfd_channel *priv)
+{
+	struct net_device_stats *stats = &priv->ndev->stats;
+	struct canfd_frame *cf;
+	struct sk_buff *skb;
+	u32 sts = 0, id, ptr;
+	u32 ch = priv->channel;
+	u32 ridx = ch + RCANFD_RFFIFO_IDX;
+
+	id = rcar_canfd_read(priv, RCANFD_F_RFID(ridx));
+	ptr = rcar_canfd_read(priv, RCANFD_F_RFPTR(ridx));
+
+	sts = rcar_canfd_read(priv, RCANFD_F_RFFDSTS(ridx));
+	if (sts & RCANFD_RFFIFO_RFFDF)
+		skb = alloc_canfd_skb(priv->ndev, &cf);
+	else
+		skb = alloc_can_skb(priv->ndev,
+				    (struct can_frame **)&cf);
+
+	if (!skb) {
+		stats->rx_dropped++;
+		return;
+	}
+
+	if (sts & RCANFD_RFFIFO_RFFDF)
+		cf->len = can_dlc2len(RCANFD_RFFIFO_RFDLC(ptr));
+	else
+		cf->len = get_can_dlc(RCANFD_RFFIFO_RFDLC(ptr));
+
+	if (sts & RCANFD_RFFIFO_RFESI) {
+		cf->flags |= CANFD_ESI;
+		netdev_dbg(priv->ndev, "ESI Error\n");
+	}
+
+	if (id & RCANFD_RFFIFO_RFIDE)
+		cf->can_id = (id & CAN_EFF_MASK) | CAN_EFF_FLAG;
+	else
+		cf->can_id = id & CAN_SFF_MASK;
+
+	if (!(sts & RCANFD_RFFIFO_RFFDF) && (id & RCANFD_RFFIFO_RFRTR)) {
+		cf->can_id |= CAN_RTR_FLAG;
+	} else {
+		if (sts & RCANFD_RFFIFO_RFBRS)
+			cf->flags |= CANFD_BRS;
+
+		rcar_canfd_get_data(cf, priv, RCANFD_F_RFDF(ridx, 0));
+	}
+
+	/* Write 0xff to RFPC to increment the CPU-side
+	 * pointer of the Rx FIFO
+	 */
+	rcar_canfd_write(priv, RCANFD_RFPCTR(ridx), 0xff);
+
+	can_led_event(priv->ndev, CAN_LED_EVENT_RX);
+
+	stats->rx_bytes += cf->len;
+	stats->rx_packets++;
+	netif_receive_skb(skb);
+}
+
+static int rcar_canfd_rx_poll(struct napi_struct *napi, int quota)
+{
+	struct rcar_canfd_channel *priv =
+		container_of(napi, struct rcar_canfd_channel, napi);
+	int num_pkts;
+	u32 sts;
+	u32 ch = priv->channel;
+	u32 ridx = ch + RCANFD_RFFIFO_IDX;
+
+	for (num_pkts = 0; num_pkts < quota; num_pkts++) {
+		sts = rcar_canfd_read(priv, RCANFD_RFSTS(ridx));
+		/* Clear interrupt bit */
+		if (sts & RCANFD_RFFIFO_RFIF)
+			rcar_canfd_write(priv, RCANFD_RFSTS(ridx),
+					 sts & ~RCANFD_RFFIFO_RFIF);
+
+		/* Check FIFO empty condition */
+		if (sts & RCANFD_RFFIFO_RFEMP)
+			break;
+
+		rcar_canfd_rx_pkt(priv);
+	}
+
+	/* All packets processed */
+	if (num_pkts < quota) {
+		napi_complete(napi);
+		/* Enable Rx FIFO interrupts */
+		rcar_canfd_set_bit(priv, RCANFD_RFCC(ridx), RCANFD_RFFIFO_RFIE);
+	}
+	return num_pkts;
+}
+
+static int rcar_canfd_do_set_mode(struct net_device *ndev, enum can_mode mode)
+{
+	int err;
+
+	switch (mode) {
+	case CAN_MODE_START:
+		err = rcar_canfd_start(ndev);
+		if (err)
+			return err;
+		netif_wake_queue(ndev);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int rcar_canfd_get_berr_counter(const struct net_device *dev,
+				       struct can_berr_counter *bec)
+{
+	struct rcar_canfd_channel *priv = netdev_priv(dev);
+	u32 val, ch = priv->channel;
+
+	/* Peripheral clock is already enabled in probe */
+	val = rcar_canfd_read(priv, RCANFD_CSTS(ch));
+	bec->txerr = RCANFD_CSTS_TECCNT(val);
+	bec->rxerr = RCANFD_CSTS_RECCNT(val);
+	return 0;
+}
+
+static const struct net_device_ops rcar_canfd_netdev_ops = {
+	.ndo_open = rcar_canfd_open,
+	.ndo_stop = rcar_canfd_close,
+	.ndo_start_xmit = rcar_canfd_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
+};
+
+static int rcar_canfd_channel_probe(struct rcar_canfd_global *gpriv, u32 ch)
+{
+	struct platform_device *pdev = gpriv->pdev;
+	struct rcar_canfd_channel *priv;
+	struct net_device *ndev;
+	int err = -ENODEV;
+
+	ndev = alloc_candev(sizeof(*priv), RCANFD_FIFO_DEPTH);
+	if (!ndev) {
+		dev_err(&pdev->dev, "alloc_candev() failed\n");
+		err = -ENOMEM;
+		goto fail;
+	}
+	priv = netdev_priv(ndev);
+
+	ndev->netdev_ops = &rcar_canfd_netdev_ops;
+	ndev->flags |= IFF_ECHO;
+	priv->ndev = ndev;
+	priv->base = gpriv->base;
+	priv->channel = ch;
+	priv->can.clock.freq = gpriv->freq;
+	dev_info(&pdev->dev, "can_clk rate is %u\n", priv->can.clock.freq);
+
+	priv->can.bittiming_const = &rcar_canfd_nom_bittiming_const;
+	priv->can.data_bittiming_const =
+		&rcar_canfd_data_bittiming_const;
+
+	/* Controller starts in CAN FD mode, which supports classical CAN and
+	 * CAN FD frames. For classical CAN frames only configurations, data
+	 * bitrate should be configured the same as nominal bitrate.
+	 */
+	priv->can.ctrlmode_supported = CAN_CTRLMODE_BERR_REPORTING |
+		CAN_CTRLMODE_FD;
+
+	priv->can.do_set_mode = rcar_canfd_do_set_mode;
+	priv->can.do_get_berr_counter = rcar_canfd_get_berr_counter;
+	priv->gpriv = gpriv;
+	SET_NETDEV_DEV(ndev, &pdev->dev);
+
+	netif_napi_add(ndev, &priv->napi, rcar_canfd_rx_poll,
+		       RCANFD_NAPI_WEIGHT);
+	err = register_candev(ndev);
+	if (err) {
+		dev_err(&pdev->dev,
+			"register_candev() failed, error %d\n", err);
+		goto fail_candev;
+	}
+
+	rcar_canfd_init_debugfs(priv);
+	devm_can_led_init(ndev);
+	gpriv->ch[priv->channel] = priv;
+	dev_info(&pdev->dev, "device registered (channel %u)\n", priv->channel);
+	return 0;
+
+fail_candev:
+	netif_napi_del(&priv->napi);
+	free_candev(ndev);
+fail:
+	return err;
+}
+
+static void rcar_canfd_channel_remove(struct rcar_canfd_global *gpriv, u32 ch)
+{
+	struct rcar_canfd_channel *priv = gpriv->ch[ch];
+
+	if (priv) {
+		unregister_candev(priv->ndev);
+		netif_napi_del(&priv->napi);
+		free_candev(priv->ndev);
+	}
+}
+
+static int rcar_canfd_probe(struct platform_device *pdev)
+{
+	struct resource *mem;
+	void __iomem *addr;
+	u32 sts, ch;
+	struct rcar_canfd_global *gpriv;
+	struct device_node *of_child;
+	unsigned long channels_mask = 0;
+	int err, ch_irq, g_irq;
+
+	of_child = of_get_child_by_name(pdev->dev.of_node, "channel0");
+	if (of_child && of_device_is_available(of_child))
+		channels_mask |= BIT(0);	/* Channel 0 */
+
+	of_child = of_get_child_by_name(pdev->dev.of_node, "channel1");
+	if (of_child && of_device_is_available(of_child))
+		channels_mask |= BIT(1);	/* Channel 1 */
+
+	ch_irq = platform_get_irq(pdev, 0);
+	if (ch_irq < 0) {
+		dev_err(&pdev->dev, "no Channel IRQ resource\n");
+		err = ch_irq;
+		goto fail_dev;
+	}
+
+	g_irq = platform_get_irq(pdev, 1);
+	if (g_irq < 0) {
+		dev_err(&pdev->dev, "no Global IRQ resource\n");
+		err = g_irq;
+		goto fail_dev;
+	}
+
+	/* Global controller context */
+	gpriv = devm_kzalloc(&pdev->dev, sizeof(*gpriv), GFP_KERNEL);
+	if (!gpriv) {
+		err = -ENOMEM;
+		goto fail_dev;
+	}
+	gpriv->pdev = pdev;
+	gpriv->channels_mask = channels_mask;
+
+	/* Peripheral clock */
+	gpriv->clkp = devm_clk_get(&pdev->dev, "fck");
+	if (IS_ERR(gpriv->clkp)) {
+		err = PTR_ERR(gpriv->clkp);
+		dev_err(&pdev->dev, "cannot get peripheral clock, error %d\n",
+			err);
+		goto fail_dev;
+	}
+
+	/* fCAN clock: Pick External clock. If not available fallback to
+	 * CANFD clock
+	 */
+	gpriv->can_clk = devm_clk_get(&pdev->dev, "can_clk");
+	if (IS_ERR(gpriv->can_clk)) {
+		gpriv->can_clk = devm_clk_get(&pdev->dev, "canfd");
+		if (IS_ERR(gpriv->can_clk)) {
+			err = PTR_ERR(gpriv->can_clk);
+			dev_err(&pdev->dev,
+				"cannot get canfd clock, error %d\n", err);
+			goto fail_dev;
+		}
+		gpriv->clock_select = RCANFD_CANFDCLK;
+
+	} else {
+		gpriv->clock_select = RCANFD_EXTCLK;
+	}
+	gpriv->freq = clk_get_rate(gpriv->can_clk);
+
+	if (gpriv->clock_select == RCANFD_CANFDCLK)
+		/* CANFD clock is further divided by (1/2) within the IP */
+		gpriv->freq /= 2;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	addr = devm_ioremap_resource(&pdev->dev, mem);
+	if (IS_ERR(addr)) {
+		err = PTR_ERR(addr);
+		goto fail_dev;
+	}
+	gpriv->base = addr;
+
+	/* Request IRQ that's common for both channels */
+	err = devm_request_irq(&pdev->dev, ch_irq,
+			       rcar_canfd_channel_interrupt, 0,
+			       "canfd.chn", gpriv);
+	if (err) {
+		dev_err(&pdev->dev, "devm_request_irq(%d) failed, error %d\n",
+			ch_irq, err);
+		goto fail_dev;
+	}
+	err = devm_request_irq(&pdev->dev, g_irq,
+			       rcar_canfd_global_interrupt, 0,
+			       "canfd.gbl", gpriv);
+	if (err) {
+		dev_err(&pdev->dev, "devm_request_irq(%d) failed, error %d\n",
+			g_irq, err);
+		goto fail_dev;
+	}
+
+	/* Enable peripheral clock for register access */
+	err = clk_prepare_enable(gpriv->clkp);
+	if (err) {
+		dev_err(&pdev->dev,
+			"failed to enable peripheral clock, error %d\n", err);
+		goto fail_dev;
+	}
+
+	err = rcar_canfd_reset_controller(gpriv);
+	if (err) {
+		dev_err(&pdev->dev, "reset controller failed\n");
+		goto fail_clk;
+	}
+
+	/* Controller in Global reset & Channel reset mode */
+	rcar_canfd_configure_controller(gpriv);
+
+	/* Configure per channel attributes */
+	for_each_set_bit(ch, &gpriv->channels_mask, RCANFD_NUM_CHANNELS) {
+		/* Configure Channel's Rx fifo */
+		rcar_canfd_configure_rx(gpriv, ch);
+
+		/* Configure Channel's Tx (Common) fifo */
+		rcar_canfd_configure_tx(gpriv, ch);
+
+		/* Configure receive rules */
+		rcar_canfd_configure_afl_rules(gpriv, ch);
+	}
+
+	/* Configure inter-channel test mode when both channels enabled */
+	if ((testmode == RCANFD_TESTMODE_INTERCHANNEL) &&
+	    (gpriv->channels_mask == RCANFD_CHANNELS_MASK)) {
+		err = rcar_canfd_configure_interch_mode(gpriv);
+		if (err)
+			goto fail_clk;
+	}
+
+	/* Configure common interrupts */
+	rcar_canfd_enable_global_interrupts(gpriv);
+
+	/* Start Global operation mode */
+	rcar_canfd_update_bit(gpriv, RCANFD_GCTR, RCANFD_GCTR_MODEMASK,
+			      RCANFD_GCTR_GOPM);
+
+	/* Verify mode change */
+	err = readl_poll_timeout((gpriv->base + RCANFD_GSTS), sts,
+				 !(sts & RCANFD_GSTS_GNOPM), 2, 500000);
+	if (err) {
+		dev_err(&pdev->dev, "global operational mode failed\n");
+		goto fail_mode;
+	}
+
+	for_each_set_bit(ch, &gpriv->channels_mask, RCANFD_NUM_CHANNELS) {
+		err = rcar_canfd_channel_probe(gpriv, ch);
+		if (err)
+			goto fail_channel;
+	}
+
+	platform_set_drvdata(pdev, gpriv);
+	if (testmode)
+		dev_info(&pdev->dev, "in %s test mode\n",
+			 (testmode == RCANFD_TESTMODE_INTERNAL_LOOPBACK) ?
+			 "internal loopback" : "inter-channel");
+
+	dev_info(&pdev->dev, "global operational state (clk %d)\n",
+		 gpriv->clock_select);
+	return 0;
+
+fail_channel:
+	for_each_set_bit(ch, &gpriv->channels_mask, RCANFD_NUM_CHANNELS)
+		rcar_canfd_channel_remove(gpriv, ch);
+fail_mode:
+	rcar_canfd_disable_global_interrupts(gpriv);
+fail_clk:
+	clk_disable_unprepare(gpriv->clkp);
+fail_dev:
+	return err;
+}
+
+static int rcar_canfd_remove(struct platform_device *pdev)
+{
+	struct rcar_canfd_global *gpriv = platform_get_drvdata(pdev);
+	struct rcar_canfd_channel *priv;
+	u32 ch;
+
+	rcar_canfd_reset_controller(gpriv);
+	rcar_canfd_disable_global_interrupts(gpriv);
+
+	for_each_set_bit(ch, &gpriv->channels_mask, RCANFD_NUM_CHANNELS) {
+		priv = gpriv->ch[ch];
+		if (priv) {
+			rcar_canfd_disable_channel_interrupts(priv);
+			rcar_canfd_remove_debugfs(priv);
+			unregister_candev(priv->ndev);
+			netif_napi_del(&priv->napi);
+			free_candev(priv->ndev);
+		}
+	}
+
+	/* Enter global sleep mode */
+	rcar_canfd_set_bit(gpriv, RCANFD_GCTR, RCANFD_GCTR_SLPR);
+	clk_disable_unprepare(gpriv->clkp);
+	return 0;
+}
+
+static int __maybe_unused rcar_canfd_suspend(struct device *dev)
+{
+	return 0;
+}
+
+static int __maybe_unused rcar_canfd_resume(struct device *dev)
+{
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(rcar_canfd_pm_ops, rcar_canfd_suspend,
+			 rcar_canfd_resume);
+
+static const struct of_device_id rcar_canfd_of_table[] __maybe_unused = {
+	{ .compatible = "renesas,rcar-gen3-canfd" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, rcar_canfd_of_table);
+
+static struct platform_driver rcar_canfd_driver = {
+	.driver = {
+		.name = RCANFD_DRV_NAME,
+		.of_match_table = of_match_ptr(rcar_canfd_of_table),
+		.pm = &rcar_canfd_pm_ops,
+	},
+	.probe = rcar_canfd_probe,
+	.remove = rcar_canfd_remove,
+};
+
+module_platform_driver(rcar_canfd_driver);
+
+MODULE_AUTHOR("Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("CAN FD driver for Renesas R-Car SoC");
+MODULE_ALIAS("platform:" RCANFD_DRV_NAME);