4 files changed, 79 insertions, 5 deletions

diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index d7cb843..6652a81 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -694,13 +694,24 @@ out:
  */
 static void ufs_qcom_advertise_quirks(struct ufs_hba *hba)
 {
+	struct ufs_qcom_host *host = hba->priv;
 
+	if (host->hw_ver.major == 0x1)
+		hba->quirks |= UFSHCD_QUIRK_DELAY_BEFORE_DME_CMDS;
 
-	/*
-	 * TBD
-	 * here we should be advertising controller quirks according to
-	 * controller version.
-	 */
+	if (host->hw_ver.major >= 0x2) {
+		if (!ufs_qcom_cap_qunipro(host))
+			/* Legacy UniPro mode still need following quirks */
+			hba->quirks |= UFSHCD_QUIRK_DELAY_BEFORE_DME_CMDS;
+	}
+}
+
+static void ufs_qcom_set_caps(struct ufs_hba *hba)
+{
+	struct ufs_qcom_host *host = hba->priv;
+
+	if (host->hw_ver.major >= 0x2)
+		host->caps = UFS_QCOM_CAP_QUNIPRO;
 }
 
 static int ufs_qcom_get_bus_vote(struct ufs_qcom_host *host,
@@ -938,6 +949,7 @@ static int ufs_qcom_init(struct ufs_hba *hba)
 	if (err)
 		goto out_disable_phy;
 
+	ufs_qcom_set_caps(hba);
 	ufs_qcom_advertise_quirks(hba);
 
 	hba->caps |= UFSHCD_CAP_CLK_GATING | UFSHCD_CAP_CLK_SCALING;
diff --git a/drivers/scsi/ufs/ufs-qcom.h b/drivers/scsi/ufs/ufs-qcom.h
index 9037396..db2c0a0 100644
--- a/drivers/scsi/ufs/ufs-qcom.h
+++ b/drivers/scsi/ufs/ufs-qcom.h
@@ -158,6 +158,16 @@ struct ufs_hw_version {
 	u8 major;
 };
 struct ufs_qcom_host {
+
+	/*
+	 * Set this capability if host controller supports the QUniPro mode
+	 * and if driver wants the Host controller to operate in QUniPro mode.
+	 * Note: By default this capability will be kept enabled if host
+	 * controller supports the QUniPro mode.
+	 */
+	#define UFS_QCOM_CAP_QUNIPRO	UFS_BIT(0)
+	u32 caps;
+
 	struct phy *generic_phy;
 	struct ufs_hba *hba;
 	struct ufs_qcom_bus_vote bus_vote;
@@ -175,4 +185,12 @@ struct ufs_qcom_host {
 #define ufs_qcom_is_link_active(hba) ufshcd_is_link_active(hba)
 #define ufs_qcom_is_link_hibern8(hba) ufshcd_is_link_hibern8(hba)
 
+static inline bool ufs_qcom_cap_qunipro(struct ufs_qcom_host *host)
+{
+	if (host->caps & UFS_QCOM_CAP_QUNIPRO)
+		return true;
+	else
+		return false;
+}
+
 #endif /* UFS_QCOM_H_ */
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 5d60a86..dfd72af 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -183,6 +183,7 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
 static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on);
 static int ufshcd_uic_hibern8_exit(struct ufs_hba *hba);
 static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba);
+static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba *hba);
 static int ufshcd_host_reset_and_restore(struct ufs_hba *hba);
 static irqreturn_t ufshcd_intr(int irq, void *__hba);
 static int ufshcd_config_pwr_mode(struct ufs_hba *hba,
@@ -972,6 +973,8 @@ ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd)
 
 	ufshcd_hold(hba, false);
 	mutex_lock(&hba->uic_cmd_mutex);
+	ufshcd_add_delay_before_dme_cmd(hba);
+
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	ret = __ufshcd_send_uic_cmd(hba, uic_cmd);
 	spin_unlock_irqrestore(hba->host->host_lock, flags);
@@ -2058,6 +2061,37 @@ static int ufshcd_dme_link_startup(struct ufs_hba *hba)
 	return ret;
 }
 
+static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba *hba)
+{
+	#define MIN_DELAY_BEFORE_DME_CMDS_US	1000
+	unsigned long min_sleep_time_us;
+
+	if (!(hba->quirks & UFSHCD_QUIRK_DELAY_BEFORE_DME_CMDS))
+		return;
+
+	/*
+	 * last_dme_cmd_tstamp will be 0 only for 1st call to
+	 * this function
+	 */
+	if (unlikely(!ktime_to_us(hba->last_dme_cmd_tstamp))) {
+		min_sleep_time_us = MIN_DELAY_BEFORE_DME_CMDS_US;
+	} else {
+		unsigned long delta =
+			(unsigned long) ktime_to_us(
+				ktime_sub(ktime_get(),
+				hba->last_dme_cmd_tstamp));
+
+		if (delta < MIN_DELAY_BEFORE_DME_CMDS_US)
+			min_sleep_time_us =
+				MIN_DELAY_BEFORE_DME_CMDS_US - delta;
+		else
+			return; /* no more delay required */
+	}
+
+	/* allow sleep for extra 50us if needed */
+	usleep_range(min_sleep_time_us, min_sleep_time_us + 50);
+}
+
 /**
  * ufshcd_dme_set_attr - UIC command for DME_SET, DME_PEER_SET
  * @hba: per adapter instance
@@ -2157,6 +2191,7 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd)
 
 	mutex_lock(&hba->uic_cmd_mutex);
 	init_completion(&uic_async_done);
+	ufshcd_add_delay_before_dme_cmd(hba);
 
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	hba->uic_async_done = &uic_async_done;
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 4a574aa..b47ff07 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -366,6 +366,7 @@ struct ufs_init_prefetch {
  * @saved_err: sticky error mask
  * @saved_uic_err: sticky UIC error mask
  * @dev_cmd: ufs device management command information
+ * @last_dme_cmd_tstamp: time stamp of the last completed DME command
  * @auto_bkops_enabled: to track whether bkops is enabled in device
  * @vreg_info: UFS device voltage regulator information
  * @clk_list_head: UFS host controller clocks list node head
@@ -416,6 +417,13 @@ struct ufs_hba {
 	unsigned int irq;
 	bool is_irq_enabled;
 
+	/*
+	 * delay before each dme command is required as the unipro
+	 * layer has shown instabilities
+	 */
+	#define UFSHCD_QUIRK_DELAY_BEFORE_DME_CMDS		UFS_BIT(0)
+
+	unsigned int quirks;	/* Deviations from standard UFSHCI spec. */
 
 	wait_queue_head_t tm_wq;
 	wait_queue_head_t tm_tag_wq;
@@ -446,6 +454,7 @@ struct ufs_hba {
 
 	/* Device management request data */
 	struct ufs_dev_cmd dev_cmd;
+	ktime_t last_dme_cmd_tstamp;
 
 	/* Keeps information of the UFS device connected to this host */
 	struct ufs_dev_info dev_info;