Re: [PATCH] ARM: rockchip: restore dapswjdp after suspend

From: Doug Anderson
Date: Thu May 21 2015 - 11:41:00 EST


Huang Tao,

On Wed, May 20, 2015 at 7:02 PM, Huang, Tao <huangtao@xxxxxxxxxxxxxx> wrote:
>> It turns out that's not a safe assumption. In some cases (pending
>> interrupts) it's possible that the WFI might act as a no-op and the
>> MaskROM will never run.
>
>
> I don't think this can happen. It seems we set PMU_GLOBAL_INT_DISABLE
> bit, which means in power off flow, the IRQ will not accepted until the
> ARM is power off. Do you see the SGRF_CPU_CON0[0] is 0 after resume?

>From testing, it appears that it can happen that the WFI might act as a no-op.

...but you're right in pointing out that unless we can solve the
PMU_GLOBAL_INT_DISABLE() problem then this patch here to fix
DAPDEVICEEN isn't too useful. I was hoping to fix the
PMU_GLOBAL_INT_DISABLE() in
<https://chromium-review.googlesource.com/#/c/272442/> or find a
similar solution. ...if we can's solve that though, then I'm not sure
what to suggest.


> Anyway, restore the value is okay, which make the code more symmetrically

OK. Heiko: applying this won't hurt, but it will only be useful if we
find a way to return from the WFI successfully...

-Doug
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