Re: [PATCH v6] ACPI: skip IRQ override on AMD Zen platforms

[Limonciello, Mario]

On 7/14/2022 13:35, Rafael J. Wysocki wrote:
> On Tue, Jul 12, 2022 at 4:01 AM Chuanhong Guo <gch981213@xxxxxxxxx> wrote:
> > IRQ override isn't needed on modern AMD Zen systems.
> > There's an active low keyboard IRQ on AMD Ryzen 6000 and it will stay
> > this way on newer platforms. This IRQ override breaks keyboards for
> > almost all Ryzen 6000 laptops currently on the market.
> >
> > Skip this IRQ override for all AMD Zen platforms because this IRQ
> > override is supposed to be a workaround for buggy ACPI DSDT and we can't
> > have a long list of all future AMD CPUs/Laptops in the kernel code.
> > If a device with buggy ACPI DSDT shows up, a separated list containing
> > just them should be created.
> >
> > Suggested-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> > Signed-off-by: Chuanhong Guo <gch981213@xxxxxxxxx>
>
> I need an ACK from Mario here.

Sure.  As he mentioned this polarity change is needed going forward.
So if we end up with a similar regression as the Baytrail attempt to 
make this generic and need to revert we'll need to find a different 
heuristic to make it generic on RMB and later.

Acked-by: Mario Limonciello <mario.limonciello@xxxxxxx>

Here's some other tags to pick up too in the commit message.

Tested-by: XiaoYan Li <lxy.lixiaoyan@xxxxxxxxx>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216118

> > ---
> > Change sice v5: reworked
> >
> >   drivers/acpi/resource.c | 10 ++++++++++
> >   1 file changed, 10 insertions(+)
> >
> > diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
> > index c2d494784425..510cdec375c4 100644
> > --- a/drivers/acpi/resource.c
> > +++ b/drivers/acpi/resource.c
> > @@ -416,6 +416,16 @@ static bool acpi_dev_irq_override(u32 gsi, u8 triggering, u8 polarity,
> >   {
> >          int i;
> >
> > +#ifdef CONFIG_X86
> > +       /*
> > +        * IRQ override isn't needed on modern AMD Zen systems and
> > +        * this override breaks active low IRQs on AMD Ryzen 6000 and
> > +        * newer systems. Skip it.
> > +        */
> > +       if (boot_cpu_has(X86_FEATURE_ZEN))
> > +               return false;
> > +#endif
> > +
> >          for (i = 0; i < ARRAY_SIZE(skip_override_table); i++) {
> >                  const struct irq_override_cmp *entry = &skip_override_table[i];
> >
> > --
> > 2.36.1