On 8/14/24 10:16 PM, Manivannan Sadhasivam via B4 Relay wrote:
From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
SM8550 SoC supports the UFSHCI 3.0 spec, but it reports a bogus value of
1 in the reserved 'Legacy Queue & Single Doorbell Support (LSDBS)' field of
the Controller Capabilities register. This field is supposed to read 0 as
per the spec.
But starting with commit 0c60eb0cc320 ("scsi: ufs: core: Check LSDBS cap
when !mcq"), ufshcd driver is now relying on the LSDBS field to decide when
to use the legacy doorbell mode if MCQ is not supported. And this ends up
breaking UFS on SM8550:
ufshcd-qcom 1d84000.ufs: ufshcd_init: failed to initialize (legacy doorbell mode not supported)
ufshcd-qcom 1d84000.ufs: error -EINVAL: Initialization failed with error -22
So use the UFSHCD_QUIRK_BROKEN_LSDBS_CAP quirk for SM8550 SoC so that the
ufshcd driver could use legacy doorbell mode correctly.
Fixes: 0c60eb0cc320 ("scsi: ufs: core: Check LSDBS cap when !mcq")
Since this patch depends on the previous two patches, the previous two
patches probably need a "Cc: stable" tag. Otherwise the stable
maintainers will have a hard time figuring out which patches this patch
depends on.
Since this patch by itself looks good to me:
Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx>
