[PATCH v1 08/11] scsi: ufs: handle errors from PHY_ADAPTER_ERROR register

From: Subhash Jadavani
Date: Wed Nov 23 2016 - 19:32:50 EST


From: Dolev Raviv <draviv@xxxxxxxxxxxxxx>

The PHY_ADAPTER_ERROR status register indicates PHY lane errors
reported by the M-PHY layer. In some occasions the controller
can recover from such errors. When the error is not recoverable,
a stuck DB error will occur. Since the stuck DB error is spotted
separately, no action other than clearing the register is necessary.

Signed-off-by: Dolev Raviv <draviv@xxxxxxxxxxxxxx>
Signed-off-by: Subhash Jadavani <subhashj@xxxxxxxxxxxxxx>
---
drivers/scsi/ufs/ufshcd.c | 11 +++++++++++
drivers/scsi/ufs/ufshci.h | 1 +
2 files changed, 12 insertions(+)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 16c5c50..ec4c99a 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4215,6 +4215,17 @@ static void ufshcd_update_uic_error(struct ufs_hba *hba)
{
u32 reg;

+ /* PHY layer lane error */
+ reg = ufshcd_readl(hba, REG_UIC_ERROR_CODE_PHY_ADAPTER_LAYER);
+ /* Ignore LINERESET indication, as this is not an error */
+ if ((reg & UIC_PHY_ADAPTER_LAYER_ERROR) &&
+ (reg & UIC_PHY_ADAPTER_LAYER_LANE_ERR_MASK))
+ /*
+ * To know whether this error is fatal or not, DB timeout
+ * must be checked but this error is handled separately.
+ */
+ dev_dbg(hba->dev, "%s: UIC Lane error reported\n", __func__);
+
/* PA_INIT_ERROR is fatal and needs UIC reset */
reg = ufshcd_readl(hba, REG_UIC_ERROR_CODE_DATA_LINK_LAYER);
if (reg & UIC_DATA_LINK_LAYER_ERROR_PA_INIT)
diff --git a/drivers/scsi/ufs/ufshci.h b/drivers/scsi/ufs/ufshci.h
index 9599741..bfabb08 100644
--- a/drivers/scsi/ufs/ufshci.h
+++ b/drivers/scsi/ufs/ufshci.h
@@ -166,6 +166,7 @@ enum {
/* UECPA - Host UIC Error Code PHY Adapter Layer 38h */
#define UIC_PHY_ADAPTER_LAYER_ERROR UFS_BIT(31)
#define UIC_PHY_ADAPTER_LAYER_ERROR_CODE_MASK 0x1F
+#define UIC_PHY_ADAPTER_LAYER_LANE_ERR_MASK 0xF

/* UECDL - Host UIC Error Code Data Link Layer 3Ch */
#define UIC_DATA_LINK_LAYER_ERROR UFS_BIT(31)
--
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