[PATCH 0/3] ARM: Fix reset in SPL if SYSRESET is not used

[Stefano Babic]

On 23.04.20 13:18, Harald Seiler wrote:
> Hello,
> 
> On Wed, 2020-03-04 at 15:23 +0100, Harald Seiler wrote:
>> Hello,
>>
>> continuing on the discussion around Claudius' patch for fixing reset in SPL [1]
>> we have taken a closer look at the issue.  To quickly summarize the situation:
>>
>>     The original patch was to enable the generic ARM implementation of
>>     `do_reset` if CONFIG_SYSRESET is not enabled in SPL.  This would break
>>     compilation for some boards which define their own `do_reset` in
>>     `board/*/spl.c`.
>>
>>     To be more specific, the following 4 boards have this custom `do_reset`:
>>
>>         - toradex/verdin-imx8mm
>>         - freescale/imx8mn_evk
>>         - freescale/imx8mm_evk
>>         - freescale/imx8mp_evk
>>
>> I hope we can all agree that `do_reset` is not at all meant to be implemented
>> in board files.  From looking at the related code for imx8m, it feels like this
>> was just a workaround hack to archieve the same thing which Claudius has fixed.
>> So this patch series reverts the addition of `do_reset` implementations in
>> imx8m board files and instead switches to using the proper fix provided by
>> Claudius.
>>
>>
>> Additionally, the custom do_reset implementations were passing an address
>> (WDOG1_BASE_ADDR) to `reset_cpu()` instead of 0.  This is the only place in the
>> entire U-Boot tree where this happens.  Instead, all other implementations
>> simply ignore the parameter and 0 is passed by callers.  It looks a lot like
>> this is a legacy left-over which makes me think that using it for a (hard-coded)
>> watchdog address is not a good idea as it breaks convention with the rest of
>> U-Boot.
>>
>> [1]: https://patchwork.ozlabs.org/patch/1201959 
>>
>> Claudius Heine (3):
>>   ARM: reset: use do_reset in SPL/TPL if SYSRESET was not enabled for
>>     them
>>   imx: imx8m*: Remove do_reset from board files
>>   imx: imx8m: Don't use the addr parameter of reset_cpu
>>
>>  arch/arm/lib/Makefile             | 2 +-
>>  arch/arm/mach-imx/imx8m/soc.c     | 5 +----
>>  board/freescale/imx8mm_evk/spl.c  | 9 ---------
>>  board/freescale/imx8mn_evk/spl.c  | 9 ---------
>>  board/freescale/imx8mp_evk/spl.c  | 9 ---------
>>  board/toradex/verdin-imx8mm/spl.c | 9 ---------
>>  6 files changed, 2 insertions(+), 41 deletions(-)
>>
> 
> Quick question, what is the situation with this series?  Is there anything
> which needs to be addressed?

Patches are fine IMHO - I will merge them soon.

Stefano

> 
> Without it, CONFIG_SPL_USB_SDP_SUPPORT is broken on the imx6q hardware
> I am working with and I guess the same issue might exist on many other
> boards as well (The USB stack needs a do_reset() implementation in SPL).
> 
> Regards,
> 


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