scsi: ufs: handle LINERESET during hibern8

If LINERESET was detected during Hibern8 operation, link moves to
default PWM-G1 mode hence full reinit is required to move link to
HS speeds.

Change-Id: I4cdcbd31b5fa5ceac0eea7c743ea9286f231b80b
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>

3 files changed, 32 insertions, 5 deletions

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 862d56e78086..b5d08cfaa694 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4132,7 +4132,13 @@ static int __ufshcd_uic_hibern8_enter(struct ufs_hba *hba)
 	trace_ufshcd_profile_hibern8(dev_name(hba->dev), "enter",
 			     ktime_to_us(ktime_sub(ktime_get(), start)), ret);
 
-	if (ret) {
+	/*
+	 * Do full reinit if enter failed or if LINERESET was detected during
+	 * Hibern8 operation. After LINERESET, link moves to default PWM-G1
+	 * mode hence full reinit is required to move link to HS speeds.
+	 */
+	if (ret || hba->full_init_linereset) {
+		hba->full_init_linereset = false;
 		ufshcd_update_error_stats(hba, UFS_ERR_HIBERN8_ENTER);
 		dev_err(hba->dev, "%s: hibern8 enter failed. ret = %d",
 			__func__, ret);
@@ -4175,8 +4181,13 @@ int ufshcd_uic_hibern8_exit(struct ufs_hba *hba)
 	ret = ufshcd_uic_pwr_ctrl(hba, &uic_cmd);
 	trace_ufshcd_profile_hibern8(dev_name(hba->dev), "exit",
 			     ktime_to_us(ktime_sub(ktime_get(), start)), ret);
-
-	if (ret) {
+	/*
+	 * Do full reinit if exit failed or if LINERESET was detected during
+	 * Hibern8 operation. After LINERESET, link moves to default PWM-G1
+	 * mode hence full reinit is required to move link to HS speeds.
+	 */
+	if (ret || hba->full_init_linereset) {
+		hba->full_init_linereset = false;
 		ufshcd_update_error_stats(hba, UFS_ERR_HIBERN8_EXIT);
 		dev_err(hba->dev, "%s: hibern8 exit failed. ret = %d",
 			__func__, ret);
@@ -5827,9 +5838,8 @@ static void ufshcd_update_uic_error(struct ufs_hba *hba)
 
 	/* 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)) {
+			(reg & UIC_PHY_ADAPTER_LAYER_ERROR_CODE_MASK)) {
 		/*
 		 * To know whether this error is fatal or not, DB timeout
 		 * must be checked but this error is handled separately.
@@ -5837,6 +5847,20 @@ static void ufshcd_update_uic_error(struct ufs_hba *hba)
 		dev_dbg(hba->dev, "%s: UIC Lane error reported, reg 0x%x\n",
 				__func__, reg);
 		ufshcd_update_uic_reg_hist(&hba->ufs_stats.pa_err, reg);
+
+		/* Don't ignore LINERESET indication during hibern8 operation */
+		if (reg & UIC_PHY_ADAPTER_LAYER_GENERIC_ERROR) {
+			struct uic_command *cmd = hba->active_uic_cmd;
+
+			if (cmd) {
+				if ((cmd->command == UIC_CMD_DME_HIBER_ENTER)
+				 || (cmd->command == UIC_CMD_DME_HIBER_EXIT)) {
+					dev_err(hba->dev, "%s: LINERESET during hibern8, reg 0x%x\n",
+						__func__, reg);
+					hba->full_init_linereset = true;
+				}
+			}
+		}
 	}
 
 	/* PA_INIT_ERROR is fatal and needs UIC reset */
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index c0714b7bea72..94d6d7b67ca6 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -902,6 +902,8 @@ struct ufs_hba {
 	bool no_ref_clk_gating;
 
 	int scsi_block_reqs_cnt;
+
+	bool full_init_linereset;
 };
 
 /* Returns true if clocks can be gated. Otherwise false */
diff --git a/drivers/scsi/ufs/ufshci.h b/drivers/scsi/ufs/ufshci.h
index d65dad03bdd2..c0e4650a75ad 100644
--- a/drivers/scsi/ufs/ufshci.h
+++ b/drivers/scsi/ufs/ufshci.h
@@ -190,6 +190,7 @@ enum {
 
 /* UECPA - Host UIC Error Code PHY Adapter Layer 38h */
 #define UIC_PHY_ADAPTER_LAYER_ERROR			UFS_BIT(31)
+#define UIC_PHY_ADAPTER_LAYER_GENERIC_ERROR		UFS_BIT(4)
 #define UIC_PHY_ADAPTER_LAYER_ERROR_CODE_MASK		0x1F
 #define UIC_PHY_ADAPTER_LAYER_LANE_ERR_MASK		0xF