Re: [PATCH v45 2/7] mailbox/pcc.c: ignore errors on type 4 channels.
From: Adam Young
Date: Wed Jul 22 2026 - 13:23:32 EST
On 7/22/26 04:55, Sudeep Holla wrote:
On Tue, Jul 21, 2026 at 01:52:51PM -0400, Adam Young wrote:The requirement that errors are ignored is strange and I have no visibility into why it is included. It may be completely safe to ignore this rule. We have not tripped over it in our hardware, which is why I did not address it before. I cannot speak for any other implementations. However, I think the exclusion needs to be here for compliance with the protocol, otherwise we might end up with a case that we cannot support. If you can suggest an alternate way to implement the specification, please let me know and I will try to encode it.
THE ACPI spec states:Does anyone have these error status register for Type 4 ? If not it can
"[The Error status register] Contains the processor relative address,
represented in Generic Address Structure (GAS) format, of the Error status
register. This field is ignored by the OSPM on slave channels"
be optimised with that check rather than channel type check. I would rather
avoiding adding checks on the type of the channel everywhere in the code.