scsi: ufs: add capability to keep auto bkops always enabled

UFS device requires to perform bkops (back ground operations) periodically
but host can control (via auto-bkops parameter of device) when device can
perform bkops based on its performance requirements. In general, host
would like to enable the device's auto-bkops only when it's not doing any
regular data transfer but sometimes device may not behave properly if host
keeps the auto-bkops disabled. This change adds the capability to let the
device auto-bkops always enabled except suspend.

Reviewed-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-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 9c16e08..1084030 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4134,18 +4134,25 @@ out:
 }
 
 /**
- * ufshcd_force_reset_auto_bkops - force enable of auto bkops
+ * ufshcd_force_reset_auto_bkops - force reset auto bkops state
  * @hba: per adapter instance
  *
  * After a device reset the device may toggle the BKOPS_EN flag
  * to default value. The s/w tracking variables should be updated
- * as well. Do this by forcing enable of auto bkops.
+ * as well. This function would change the auto-bkops state based on
+ * UFSHCD_CAP_KEEP_AUTO_BKOPS_ENABLED_EXCEPT_SUSPEND.
  */
-static void  ufshcd_force_reset_auto_bkops(struct ufs_hba *hba)
+static void ufshcd_force_reset_auto_bkops(struct ufs_hba *hba)
 {
-       hba->auto_bkops_enabled = false;
-       hba->ee_ctrl_mask |= MASK_EE_URGENT_BKOPS;
-       ufshcd_enable_auto_bkops(hba);
+       if (ufshcd_keep_autobkops_enabled_except_suspend(hba)) {
+               hba->auto_bkops_enabled = false;
+               hba->ee_ctrl_mask |= MASK_EE_URGENT_BKOPS;
+               ufshcd_enable_auto_bkops(hba);
+       } else {
+               hba->auto_bkops_enabled = true;
+               hba->ee_ctrl_mask &= ~MASK_EE_URGENT_BKOPS;
+               ufshcd_disable_auto_bkops(hba);
+       }
 }
 
 static inline int ufshcd_get_bkops_status(struct ufs_hba *hba, u32 *status)
@@ -6564,11 +6571,15 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
                        goto set_old_link_state;
        }
 
-       /*
-        * If BKOPs operations are urgently needed at this moment then
-        * keep auto-bkops enabled or else disable it.
-        */
-       ufshcd_urgent_bkops(hba);
+       if (ufshcd_keep_autobkops_enabled_except_suspend(hba))
+               ufshcd_enable_auto_bkops(hba);
+       else
+               /*
+                * If BKOPs operations are urgently needed at this moment then
+                * keep auto-bkops enabled or else disable it.
+                */
+               ufshcd_urgent_bkops(hba);
+
        hba->clk_gating.is_suspended = false;
 
        if (hba->clk_scaling.is_allowed)

diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 787323b..f25d468 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -566,6 +566,14 @@ struct ufs_hba {
         * CAUTION: Enabling this might reduce overall UFS throughput.
         */
 #define UFSHCD_CAP_INTR_AGGR (1 << 4)
+       /*
+        * This capability allows the device auto-bkops to be always enabled
+        * except during suspend (both runtime and suspend).
+        * Enabling this capability means that device will always be allowed
+        * to do background operation when it's active but it might degrade
+        * the performance of ongoing read/write operations.
+        */
+#define UFSHCD_CAP_KEEP_AUTO_BKOPS_ENABLED_EXCEPT_SUSPEND (1 << 5)
 
        struct devfreq *devfreq;
        struct ufs_clk_scaling clk_scaling;
@@ -663,6 +671,11 @@ static inline void *ufshcd_get_variant(struct ufs_hba *hba)
        BUG_ON(!hba);
        return hba->priv;
 }
+static inline bool ufshcd_keep_autobkops_enabled_except_suspend(
+                                                       struct ufs_hba *hba)
+{
+       return hba->caps & UFSHCD_CAP_KEEP_AUTO_BKOPS_ENABLED_EXCEPT_SUSPEND;
+}
 
 extern int ufshcd_runtime_suspend(struct ufs_hba *hba);
 extern int ufshcd_runtime_resume(struct ufs_hba *hba);