Re: [PATCH 0/3] Clock fixes for Ingenic SoCs

[Paul Cercueil <paul@crapouillou.net>]

Hi Aidan,

Le mar., févr. 8 2022 at 01:00:45 +0000, Aidan MacDonald 
<aidanmacdonald.0x0@gmail.com> a écrit :
> I ran across a problem trying to get Linux running on an Ingenic 
> X1000 SoC:
> since the memory clock isn't referenced by any driver, it appears 
> unused and
> gets disabled automatically. After that, the system hangs on any RAM 
> access.
> 
> There is a hack in board-ingenic.c to forcibly enable the CPU clock, 
> but this
> is insufficient for the X1000 since the memory clock has its own gate 
> and mux
> that isn't tied to the CPU.
> 
> This patch series fixes the bug by adding CLK_IS_CRITICAL flags to 
> important
> clocks, which seems to be the approach used in many other SoC clock 
> drivers.
> 
> It's my first time submitting patches to the kernel so let me know if 
> I
> messed anything up.

You did everything good.

I think the CI20 suffered from the same problem, it would only boot as 
long as the "clk_ignore_unused" flag was added on the command line. I 
will need to try it there to see if it improved the situation.

I tested the patchset on JZ4770 and it works fine. So:

Reviewed-by: Paul Cercueil <paul@crapouillou.net>

@Stephen: I don't see any changes pending on board-ingenic.c so it 
should be safe for you to also take [PATCH 3/3] in the clk tree.

Cheers,
-Paul

> Aidan MacDonald (3):
>   clk: ingenic: Allow specifying common clock flags
>   clk: ingenic: Mark critical clocks in Ingenic SoCs
>   mips: ingenic: Do not manually reference the CPU clock
> 
>  arch/mips/generic/board-ingenic.c | 26 --------------------------
>  drivers/clk/ingenic/cgu.c         |  2 +-
>  drivers/clk/ingenic/cgu.h         |  3 +++
>  drivers/clk/ingenic/jz4725b-cgu.c |  2 ++
>  drivers/clk/ingenic/jz4740-cgu.c  |  2 ++
>  drivers/clk/ingenic/jz4760-cgu.c  |  2 ++
>  drivers/clk/ingenic/jz4770-cgu.c  |  1 +
>  drivers/clk/ingenic/jz4780-cgu.c  |  3 +++
>  drivers/clk/ingenic/x1000-cgu.c   |  3 +++
>  drivers/clk/ingenic/x1830-cgu.c   |  3 +++
>  10 files changed, 20 insertions(+), 27 deletions(-)
> 
> --
> 2.34.1
>