scsi: ufs: add quirk to disallow reset of interrupt aggregation

Some host controllers support interrupt aggregation but don't allow
resetting counter and timer in software.

Signed-off-by: Seungwon Jeon <essuuj@gmail.com>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 937355b..1ef4d46 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4659,7 +4659,8 @@ static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
         * false interrupt if device completes another request after resetting
         * aggregation and before reading the DB.
         */
-       if (ufshcd_is_intr_aggr_allowed(hba))
+       if (ufshcd_is_intr_aggr_allowed(hba) &&
+           !(hba->quirks & UFSHCI_QUIRK_SKIP_RESET_INTR_AGGR))
                ufshcd_reset_intr_aggr(hba);
 
        tr_doorbell = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);

diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 09c285f..d8c922d 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -600,6 +600,12 @@ struct ufs_hba {
         */
        #define UFSHCI_QUIRK_BROKEN_REQ_LIST_CLR                0x100
 
+       /*
+        * This quirk needs to be enabled if host controller doesn't allow
+        * that the interrupt aggregation timer and counter are reset by s/w.
+        */
+       #define UFSHCI_QUIRK_SKIP_RESET_INTR_AGGR               0x200
+
        unsigned int quirks;    /* Deviations from standard UFSHCI spec. */
 
        /* Device deviations from standard UFS device spec. */