On 09/07/2020 17:21, Douglas Anderson wrote: > If we have a per CE (Copy Engine) IRQ then we have no summary > register. Right now the code generates a summary register by > iterating over all copy engines and seeing if they have an interrupt > pending. > > This has a problem. Specifically if _none_ if the Copy Engines have s/_none_ if/_none_ of Hopefully, Kalle can just fixup before applying :-) > an interrupt pending then they might go into low power mode and > reading from their address space will cause a full system crash. This > was seen to happen when two interrupts went off at nearly the same > time. Both were handled by a single call of ath10k_snoc_napi_poll() > but, because there were two interrupts handled and thus two calls to > napi_schedule() there was still a second call to > ath10k_snoc_napi_poll() which ran with no interrupts pending. > > Instead of iterating over all the copy engines, let's just keep track > of the IRQs that fire. Then we can effectively generate our own > summary without ever needing to read the Copy Engines.
