[PATCH 4/4] [NOT FOR UPSTREAM] firmware: arm_scmi: quirk: Ignore FC bit in attributes

[Johan Hovold]

On Tue, Apr 15, 2025 at 03:29:33PM +0100, Cristian Marussi wrote:
> Some platform misreported the support of FastChannel when queried: ignore
> that bit on selected platforms.
> 
> Signed-off-by: Cristian Marussi <cristian.marussi at arm.com>
> ---
> Match features has to be set-up properly before upstreaming this.
> Ideally the out-of-spec firmware should be matched with a quirk matching
> pattern based on Vendor/SubVendor/ImplVersion....but it is NOT clear if the
> platform at hand will ship with future fixed firmwares where the ImplVersion
> field is properly handled.
> If we cannot be sure about that, we should fallback to a compatible match.
> 
> RFC->V1
> - fix QUIRKS conditions

This looks good to me now and works as intended after updating the
vendor name:

Reviewed-by: Johan Hovold <johan+linaro at kernel.org>
Tested-by: Johan Hovold <johan+linaro at kernel.org>

Interestingly, I'm no longer seeing the crash on x1e without the quirk
enabled with 6.14 and 6.15-rc2.

I still hit it immediately with 6.12 and 6.13 when accessing the cpufreq
sysfs attributes (with patch 1/4 applied):

	[   30.663577] arm-scmi arm-scmi.0.auto: timed out in resp(caller: do_xfer+0x164/0x564)

So presumably something changed in 6.14 that masks the earlier issue
when falling back to regular messaging.

Any ideas what could have caused this, Sibi?

Johan