scsi: ufs: mediatek: Support vops pre suspend to disable auto-hibern8

Mediatek UFS needs auto-hibern8 disabled before suspend. Introduce a
solution to do pre-suspend before SSU (sleep).

Link: https://lore.kernel.org/r/20211006054705.21885-1-peter.wang@mediatek.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Peter Wang <peter.wang@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ufs/ufs-exynos.c

@@ -1176,10 +1176,14 @@ static void exynos_ufs_hibern8_notify(struct ufs_hba *hba,
 	}
 }
 
-static int exynos_ufs_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
+static int exynos_ufs_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op,
+	enum ufs_notify_change_status status)
 {
 	struct exynos_ufs *ufs = ufshcd_get_variant(hba);
 
+	if (status == PRE_CHANGE)
+		return 0;
+
 	if (!ufshcd_is_link_active(hba))
 		phy_power_off(ufs->phy);
 

drivers/scsi/ufs/ufs-hisi.c

@@ -396,10 +396,14 @@ out:
 	return ret;
 }
 
-static int ufs_hisi_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
+static int ufs_hisi_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op,
+	enum ufs_notify_change_status status)
 {
 	struct ufs_hisi_host *host = ufshcd_get_variant(hba);
 
+	if (status == PRE_CHANGE)
+		return 0;
+
 	if (pm_op == UFS_RUNTIME_PM)
 		return 0;
 

drivers/scsi/ufs/ufs-mediatek.c

@@ -311,6 +311,46 @@ static void ufs_mtk_dbg_sel(struct ufs_hba *hba)
 	}
 }
 
+static void ufs_mtk_wait_idle_state(struct ufs_hba *hba,
+			    unsigned long retry_ms)
+{
+	u64 timeout, time_checked;
+	u32 val, sm;
+	bool wait_idle;
+
+	timeout = sched_clock() + retry_ms * 1000000UL;
+
+
+	/* wait a specific time after check base */
+	udelay(10);
+	wait_idle = false;
+
+	do {
+		time_checked = sched_clock();
+		ufs_mtk_dbg_sel(hba);
+		val = ufshcd_readl(hba, REG_UFS_PROBE);
+
+		sm = val & 0x1f;
+
+		/*
+		 * if state is in H8 enter and H8 enter confirm
+		 * wait until return to idle state.
+		 */
+		if ((sm >= VS_HIB_ENTER) && (sm <= VS_HIB_EXIT)) {
+			wait_idle = true;
+			udelay(50);
+			continue;
+		} else if (!wait_idle)
+			break;
+
+		if (wait_idle && (sm == VS_HCE_BASE))
+			break;
+	} while (time_checked < timeout);
+
+	if (wait_idle && sm != VS_HCE_BASE)
+		dev_info(hba->dev, "wait idle tmo: 0x%x\n", val);
+}
+
 static int ufs_mtk_wait_link_state(struct ufs_hba *hba, u32 state,
 				   unsigned long max_wait_ms)
 {
@@ -949,11 +989,37 @@ static void ufs_mtk_vreg_set_lpm(struct ufs_hba *hba, bool lpm)
 				   REGULATOR_MODE_NORMAL);
 }
 
-static int ufs_mtk_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
+static void ufs_mtk_auto_hibern8_disable(struct ufs_hba *hba)
+{
+	unsigned long flags;
+	int ret;
+
+	/* disable auto-hibern8 */
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	ufshcd_writel(hba, 0, REG_AUTO_HIBERNATE_IDLE_TIMER);
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+	/* wait host return to idle state when auto-hibern8 off */
+	ufs_mtk_wait_idle_state(hba, 5);
+
+	ret = ufs_mtk_wait_link_state(hba, VS_LINK_UP, 100);
+	if (ret)
+		dev_warn(hba->dev, "exit h8 state fail, ret=%d\n", ret);
+}
+
+static int ufs_mtk_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op,
+	enum ufs_notify_change_status status)
 {
 	int err;
 	struct arm_smccc_res res;
 
+	if (status == PRE_CHANGE) {
+		if (!ufshcd_is_auto_hibern8_supported(hba))
+			return 0;
+		ufs_mtk_auto_hibern8_disable(hba);
+		return 0;
+	}
+
 	if (ufshcd_is_link_hibern8(hba)) {
 		err = ufs_mtk_link_set_lpm(hba);
 		if (err)

drivers/scsi/ufs/ufs-mediatek.h

@@ -54,6 +54,26 @@ enum {
 	VS_LINK_CFG                 = 5,
 };
 
+/*
+ * Vendor specific host controller state
+ */
+enum {
+	VS_HCE_RESET                = 0,
+	VS_HCE_BASE                 = 1,
+	VS_HCE_OOCPR_WAIT           = 2,
+	VS_HCE_DME_RESET            = 3,
+	VS_HCE_MIDDLE               = 4,
+	VS_HCE_DME_ENABLE           = 5,
+	VS_HCE_DEFAULTS             = 6,
+	VS_HIB_IDLEEN               = 7,
+	VS_HIB_ENTER                = 8,
+	VS_HIB_ENTER_CONF           = 9,
+	VS_HIB_MIDDLE               = 10,
+	VS_HIB_WAITTIMER            = 11,
+	VS_HIB_EXIT_CONF            = 12,
+	VS_HIB_EXIT                 = 13,
+};
+
 /*
  * SiP commands
  */

drivers/scsi/ufs/ufs-qcom.c

@@ -589,11 +589,15 @@ static void ufs_qcom_device_reset_ctrl(struct ufs_hba *hba, bool asserted)
 	gpiod_set_value_cansleep(host->device_reset, asserted);
 }
 
-static int ufs_qcom_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
+static int ufs_qcom_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op,
+	enum ufs_notify_change_status status)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
 	struct phy *phy = host->generic_phy;
 
+	if (status == PRE_CHANGE)
+		return 0;
+
 	if (ufs_qcom_is_link_off(hba)) {
 		/*
 		 * Disable the tx/rx lane symbol clocks before PHY is

drivers/scsi/ufs/ufshcd.c

@@ -8844,6 +8844,10 @@ static int __ufshcd_wl_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 
 	flush_work(&hba->eeh_work);
 
+	ret = ufshcd_vops_suspend(hba, pm_op, PRE_CHANGE);
+	if (ret)
+		goto enable_scaling;
+
 	if (req_dev_pwr_mode != hba->curr_dev_pwr_mode) {
 		if (pm_op != UFS_RUNTIME_PM)
 			/* ensure that bkops is disabled */
@@ -8871,7 +8875,7 @@ vops_suspend:
 	 * vendor specific host controller register space call them before the
 	 * host clocks are ON.
 	 */
-	ret = ufshcd_vops_suspend(hba, pm_op);
+	ret = ufshcd_vops_suspend(hba, pm_op, POST_CHANGE);
 	if (ret)
 		goto set_link_active;
 	goto out;
@@ -8999,7 +9003,8 @@ static int __ufshcd_wl_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 set_old_link_state:
 	ufshcd_link_state_transition(hba, old_link_state, 0);
 vendor_suspend:
-	ufshcd_vops_suspend(hba, pm_op);
+	ufshcd_vops_suspend(hba, pm_op, PRE_CHANGE);
+	ufshcd_vops_suspend(hba, pm_op, POST_CHANGE);
 out:
 	if (ret)
 		ufshcd_update_evt_hist(hba, UFS_EVT_WL_RES_ERR, (u32)ret);

drivers/scsi/ufs/ufshcd.h

@@ -344,7 +344,8 @@ struct ufs_hba_variant_ops {
 					enum ufs_notify_change_status);
 	int	(*apply_dev_quirks)(struct ufs_hba *hba);
 	void	(*fixup_dev_quirks)(struct ufs_hba *hba);
-	int     (*suspend)(struct ufs_hba *, enum ufs_pm_op);
+	int     (*suspend)(struct ufs_hba *, enum ufs_pm_op,
+					enum ufs_notify_change_status);
 	int     (*resume)(struct ufs_hba *, enum ufs_pm_op);
 	void	(*dbg_register_dump)(struct ufs_hba *hba);
 	int	(*phy_initialization)(struct ufs_hba *);
@@ -1318,10 +1319,11 @@ static inline void ufshcd_vops_fixup_dev_quirks(struct ufs_hba *hba)
 		hba->vops->fixup_dev_quirks(hba);
 }
 
-static inline int ufshcd_vops_suspend(struct ufs_hba *hba, enum ufs_pm_op op)
+static inline int ufshcd_vops_suspend(struct ufs_hba *hba, enum ufs_pm_op op,
+				enum ufs_notify_change_status status)
 {
 	if (hba->vops && hba->vops->suspend)
-		return hba->vops->suspend(hba, op);
+		return hba->vops->suspend(hba, op, status);
 
 	return 0;
 }