Re: [PATCH] ath10k: Wait until copy complete is actually done before completing

Kalle Valo
2020-06-15T14:32:45Z

Douglas Anderson <dianders@chromium.org> wrote:

> On wcn3990 we have "per_ce_irq = true". That makes the
> ath10k_ce_interrupt_summary() function always return 0xfff. The
> ath10k_ce_per_engine_service_any() function will see this and think
> that _all_ copy engines have an interrupt. Without checking, the
> ath10k_ce_per_engine_service() assumes that if it's called that the
> "copy complete" (cc) interrupt fired. This combination seems bad.
>
> Let's add a check to make sure that the "copy complete" interrupt
> actually fired in ath10k_ce_per_engine_service().
>
> This might fix a hard-to-reproduce failure where it appears that the
> copy complete handlers run before the copy is really complete.
> Specifically a symptom was that we were seeing this on a Qualcomm
> sc7180 board:
> arm-smmu 15000000.iommu: Unhandled context fault:
> fsr=0x402, iova=0x7fdd45780, fsynr=0x30003, cbfrsynra=0xc1, cb=10
>
> Even on platforms that don't have wcn3990 this still seems like it
> would be a sane thing to do. Specifically the current IRQ handler
> comments indicate that there might be other misc interrupt sources
> firing that need to be cleared. If one of those sources was the one
> that caused the IRQ handler to be called it would also be important to
> double-check that the interrupt we cared about actually fired.
>
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath10k firmwares work very differently, on what hardware and firmware did you
test this? I'll add that information to the commit log.

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