Re: [PATCH v2 4/5] watchdog: rti_wdt: Add support for loading firmware

[Lokesh Vutla <lokeshvutla@ti.com>]

Hi Tom,

On 09/06/21 6:47 pm, Jan Kiszka wrote:
> On 07.06.21 13:44, Jan Kiszka wrote:
>> On 07.06.21 13:40, Tom Rini wrote:
>>> On Mon, Jun 07, 2021 at 03:33:52PM +0530, Lokesh Vutla wrote:
>>>> +Tom,
>>>>
>>>> Hi Tom,
>>>>
>>>> On 02/06/21 3:07 pm, Jan Kiszka wrote:
>>>>> From: Jan Kiszka <jan.kiszka@siemens.com>
>>>>>
>>>>> To avoid the need of extra boot scripting on AM65x for loading a
>>>>> watchdog firmware, add the required rproc init and loading logic for the
>>>>> first R5F core to the watchdog start handler. In case the R5F cluster is
>>>>> in lock-step mode, also initialize the second core. The firmware itself
>>>>> is embedded into U-Boot binary to ease access to it and ensure it is
>>>>> properly hashed in case of secure boot.
>>>>>
>>>>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>>>>>
>>>>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>>>>> ---
>>>>>  drivers/watchdog/Kconfig      | 20 ++++++++++++
>>>>>  drivers/watchdog/Makefile     |  5 +++
>>>>>  drivers/watchdog/rti_wdt.c    | 58 ++++++++++++++++++++++++++++++++++-
>>>>>  drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++
>>>>>  4 files changed, 102 insertions(+), 1 deletion(-)
>>>>>  create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>>>>
>>>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>>>> index f0ff2612a6..1a1fddfe9f 100644
>>>>> --- a/drivers/watchdog/Kconfig
>>>>> +++ b/drivers/watchdog/Kconfig
>>>>> @@ -209,6 +209,26 @@ config WDT_K3_RTI
>>>>>  	  Say Y here if you want to include support for the K3 watchdog
>>>>>  	  timer (RTI module) available in the K3 generation of processors.
>>>>>  
>>>>> +if WDT_K3_RTI
>>>>> +
>>>>> +config WDT_K3_RTI_LOAD_FW
>>>>> +	bool "Load watchdog firmware"
>>>>> +	depends on REMOTEPROC
>>>>> +	help
>>>>> +	  Automatically load the specified firmware image into the MCU R5F
>>>>> +	  core 0. On the AM65x, this firmware is supposed to handle the expiry
>>>>> +	  of the watchdog timer, typically by resetting the system.
>>>>> +
>>>>> +config WDT_K3_RTI_FW_FILE
>>>>> +	string "Watchdog firmware image file"
>>>>> +	default "k3-rti-wdt.fw"
>>>>> +	depends on WDT_K3_RTI_LOAD_FW
>>>>> +	help
>>>>> +	  Firmware image to be embedded into U-Boot and loaded on watchdog
>>>>> +	  start.
>>>>
>>>> I need your input on this proach. Is it okay to include the linker file unders
>>>> drivers?
>>>
>>> Maybe?  I suppose the first thing that springs to mind is why aren't we
>>> using binman and including this blob (which I happily see is GPLv2)
>>> similar to how we do things with x86 for one example.
>>>
>>
>> See https://www.mail-archive.com/u-boot@lists.denx.de/msg377894.html
>>
>> Jan
>>
> 
> Did this help to answer open questions? Otherwise, please let me know.
> 
> I'd also like to avoid that his patch alone blocks 1-3 of the series
> needless - but I would also not mind getting everything in at once.

Can you provide your reviewed-by if you are okay with this approach?

Thanks and regards,
Lokesh

> 
> Thanks,
> Jan
>