From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> 'Legacy Queue & Single Doorbell Support (SDBS)' field in the controller capabilities register is supposed to be reserved for UFSHCI 3.0 based controllers and should read as 0. But some controllers may report bogus value of 1 due to the hardware bug. So let's add a quirk to handle those controllers. If the quirk is enabled by the controller driver and MCQ is not supported, then 'hba->sdbs_sup' field will be ignored and the SCSI device will be added in legacy/single doorbell mode. Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> --- drivers/ufs/core/ufshcd.c | 5 +++-- include/ufs/ufshcd.h | 7 +++++++ 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index 168b9dbc3ada..acb6f261ecc2 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -10512,8 +10512,9 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) } if (!is_mcq_supported(hba)) { - if (!hba->sdbs_sup) { - dev_err(hba->dev, "%s: failed to initialize (legacy doorbell mode not supported)\n", + if (!(hba->quirks & UFSHCD_QUIRK_BROKEN_SDBS_CAP) && !hba->sdbs_sup) { + dev_err(hba->dev, + "%s: failed to initialize (legacy doorbell mode not supported)\n", __func__); err = -EINVAL; goto out_disable; diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h index d44b19cf9f82..85c6ea28d45d 100644 --- a/include/ufs/ufshcd.h +++ b/include/ufs/ufshcd.h @@ -676,6 +676,13 @@ enum ufshcd_quirks { * the standard best practice for managing keys). */ UFSHCD_QUIRK_KEYS_IN_PRDT = 1 << 24, + + /* + * This quirk needs to be enabled if the host controller has the broken + * Legacy Queue & Single Doorbell Support (SDBS) field in Controller + * Capabilities register. + */ + UFSHCD_QUIRK_BROKEN_SDBS_CAP = 1 << 25, }; enum ufshcd_caps { -- 2.25.1