[PATCH 2/3] aspeed-video: clear spurious interrupt bits unconditionally
zev at bewilderbeest.net
Wed Dec 23 06:14:33 AEDT 2020
On Mon, Dec 21, 2020 at 10:47:37PM CST, Joel Stanley wrote:
>On Tue, 15 Dec 2020 at 02:46, Zev Weiss <zev at bewilderbeest.net> wrote:
>> Instead of testing and conditionally clearing them one by one, we can
>> instead just unconditionally clear them all at once.
>> Signed-off-by: Zev Weiss <zev at bewilderbeest.net>
>I had a poke at the assembly and it looks like GCC is clearing the
>bits unconditionally anyway, so removing the tests provides no change.
>Combining them is a good further optimization.
>Reviewed-by: Joel Stanley <joel at jms.id.au>
>A question unrelated to this patch: Do you know why the driver doesn't
>clear the status bits in the interrupt handler? I would expect it to
>write the value of sts back to the register to ack the pending
No, I don't, and I was sort of wondering the same thing actually -- I'm
not deeply familiar with this hardware or driver though, so I was a bit
hesitant to start messing with things. (Though maybe doing so would
address the "stickiness" aspect when it does manifest.) Perhaps Eddie
or Jae can shed some light here?
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