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

Harald Seiler
2020-03-04T14:23:09Z

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(-)

--
Harald

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