Re: [PATCH 2/2] thunderbolt: Disable interrupt auto clear for rings

From: Mika Westerberg
Date: Mon Mar 13 2023 - 01:46:23 EST


Hi Mario,

On Fri, Mar 10, 2023 at 11:20:50AM -0600, Mario Limonciello wrote:
> When interrupt auto clear is programmed, any read to the interrupt
> status register will clear all interrupts. If two interrupts have
> come in before one can be serviced then this will cause lost interrupts.
>
> On AMD USB4 routers this has manifested in odd problems particularly
> with long strings of control tranfers such as reading the DROM via bit
> banging.

Nice catch! Does this mean we can drop [1] now?

[1] https://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt.git/commit/?h=next&id=8d7f459107f74fbbdde3dd5b3874d2e748cb8a21

I would still like to keep the nice refactor you did for the DROM
parsing, though.