Merge patch series "scsi: ufs: qcom: Align programming sequence as per HW spec"

Nitin Rawat <quic_nitirawa@quicinc.com> says:

This patch series adds programming support for Qualcomm UFS V4 and
above to align avoid with Hardware Specification. This patch series
will address stability and performance issues.

In this patch series below changes are taken care.

1) Register layout for DME_VS_CORE_CLK_CTRL has changed for v4 and above.
2) Adds Support to configure PA_VS_CORE_CLK_40NS_CYCLES attibute for UFS V4
   and above.
3) Adds Support to configure multiple unipro frequencies like 403MHz,
   300MHz, 202MHz, 150 MHz, 75Mhz, 37.5 MHz for Qualcomm UFS Controller V4
   and above.
4) Allow configuration of SYS1CLK_1US_REG for UFS V4 and above.

Link: https://lore.kernel.org/r/20230905052400.13935-1-quic_nitirawa@quicinc.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

3 files changed, 187 insertions, 51 deletions

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 9108bf71b092..dc1285351336 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -8722,7 +8722,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba, bool init_dev_params)
 	if (ret)
 		goto out;
 
-	if (hba->quirks & UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH) {
+	if (!hba->pm_op_in_progress &&
+	    (hba->quirks & UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH)) {
 		/* Reset the device and controller before doing reinit */
 		ufshcd_device_reset(hba);
 		ufshcd_hba_stop(hba);
diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
index d1149b1c3ed5..a6078d5939ed 100644
--- a/drivers/ufs/host/ufs-qcom.c
+++ b/drivers/ufs/host/ufs-qcom.c
@@ -93,8 +93,7 @@ static const struct __ufs_qcom_bw_table {
 static struct ufs_qcom_host *ufs_qcom_hosts[MAX_UFS_QCOM_HOSTS];
 
 static void ufs_qcom_get_default_testbus_cfg(struct ufs_qcom_host *host);
-static int ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(struct ufs_hba *hba,
-						       u32 clk_cycles);
+static int ufs_qcom_set_core_clk_ctrl(struct ufs_hba *hba, bool is_scale_up);
 
 static struct ufs_qcom_host *rcdev_to_ufs_host(struct reset_controller_dev *rcd)
 {
@@ -460,7 +459,7 @@ static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
 		return ret;
 	}
 
-	phy_set_mode_ext(phy, PHY_MODE_UFS_HS_B, host->hs_gear);
+	phy_set_mode_ext(phy, PHY_MODE_UFS_HS_B, host->phy_gear);
 
 	/* power on phy - start serdes and phy's power and clocks */
 	ret = phy_power_on(phy);
@@ -528,11 +527,20 @@ static int ufs_qcom_hce_enable_notify(struct ufs_hba *hba,
 	return err;
 }
 
-/*
+/**
+ * ufs_qcom_cfg_timers - Configure ufs qcom cfg timers
+ *
+ * @hba: host controller instance
+ * @gear: Current operating gear
+ * @hs: current power mode
+ * @rate: current operating rate (A or B)
+ * @update_link_startup_timer: indicate if link_start ongoing
+ * @is_pre_scale_up: flag to check if pre scale up condition.
  * Return: zero for success and non-zero in case of a failure.
  */
 static int ufs_qcom_cfg_timers(struct ufs_hba *hba, u32 gear,
-			       u32 hs, u32 rate, bool update_link_startup_timer)
+			       u32 hs, u32 rate, bool update_link_startup_timer,
+			       bool is_pre_scale_up)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
 	struct ufs_clk_info *clki;
@@ -563,11 +571,14 @@ static int ufs_qcom_cfg_timers(struct ufs_hba *hba, u32 gear,
 	/*
 	 * The Qunipro controller does not use following registers:
 	 * SYS1CLK_1US_REG, TX_SYMBOL_CLK_1US_REG, CLK_NS_REG &
-	 * UFS_REG_PA_LINK_STARTUP_TIMER
-	 * But UTP controller uses SYS1CLK_1US_REG register for Interrupt
+	 * UFS_REG_PA_LINK_STARTUP_TIMER.
+	 * However UTP controller uses SYS1CLK_1US_REG register for Interrupt
 	 * Aggregation logic.
-	*/
-	if (ufs_qcom_cap_qunipro(host) && !ufshcd_is_intr_aggr_allowed(hba))
+	 * It is mandatory to write SYS1CLK_1US_REG register on UFS host
+	 * controller V4.0.0 onwards.
+	 */
+	if (host->hw_ver.major < 4 && ufs_qcom_cap_qunipro(host) &&
+	    !ufshcd_is_intr_aggr_allowed(hba))
 		return 0;
 
 	if (gear == 0) {
@@ -576,8 +587,14 @@ static int ufs_qcom_cfg_timers(struct ufs_hba *hba, u32 gear,
 	}
 
 	list_for_each_entry(clki, &hba->clk_list_head, list) {
-		if (!strcmp(clki->name, "core_clk"))
-			core_clk_rate = clk_get_rate(clki->clk);
+		if (!strcmp(clki->name, "core_clk")) {
+			if (is_pre_scale_up)
+				core_clk_rate = clki->max_freq;
+			else
+				core_clk_rate = clk_get_rate(clki->clk);
+			break;
+		}
+
 	}
 
 	/* If frequency is smaller than 1MHz, set to 1MHz */
@@ -679,20 +696,17 @@ static int ufs_qcom_link_startup_notify(struct ufs_hba *hba,
 	switch (status) {
 	case PRE_CHANGE:
 		if (ufs_qcom_cfg_timers(hba, UFS_PWM_G1, SLOWAUTO_MODE,
-					0, true)) {
+					0, true, false)) {
 			dev_err(hba->dev, "%s: ufs_qcom_cfg_timers() failed\n",
 				__func__);
 			return -EINVAL;
 		}
 
-		if (ufs_qcom_cap_qunipro(host))
-			/*
-			 * set unipro core clock cycles to 150 & clear clock
-			 * divider
-			 */
-			err = ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(hba,
-									  150);
-
+		if (ufs_qcom_cap_qunipro(host)) {
+			err = ufs_qcom_set_core_clk_ctrl(hba, true);
+			if (err)
+				dev_err(hba->dev, "cfg core clk ctrl failed\n");
+		}
 		/*
 		 * Some UFS devices (and may be host) have issues if LCC is
 		 * enabled. So we are setting PA_Local_TX_LCC_Enable to 0
@@ -909,8 +923,13 @@ static int ufs_qcom_pwr_change_notify(struct ufs_hba *hba,
 			return ret;
 		}
 
-		/* Use the agreed gear */
-		host->hs_gear = dev_req_params->gear_tx;
+		/*
+		 * Update phy_gear only when the gears are scaled to a higher value. This is
+		 * because, the PHY gear settings are backwards compatible and we only need to
+		 * change the PHY gear settings while scaling to higher gears.
+		 */
+		if (dev_req_params->gear_tx > host->phy_gear)
+			host->phy_gear = dev_req_params->gear_tx;
 
 		/* enable the device ref clock before changing to HS mode */
 		if (!ufshcd_is_hs_mode(&hba->pwr_info) &&
@@ -926,7 +945,7 @@ static int ufs_qcom_pwr_change_notify(struct ufs_hba *hba,
 	case POST_CHANGE:
 		if (ufs_qcom_cfg_timers(hba, dev_req_params->gear_rx,
 					dev_req_params->pwr_rx,
-					dev_req_params->hs_rate, false)) {
+					dev_req_params->hs_rate, false, false)) {
 			dev_err(hba->dev, "%s: ufs_qcom_cfg_timers() failed\n",
 				__func__);
 			/*
@@ -1277,7 +1296,7 @@ static int ufs_qcom_init(struct ufs_hba *hba)
 	 * Power up the PHY using the minimum supported gear (UFS_HS_G2).
 	 * Switching to max gear will be performed during reinit if supported.
 	 */
-	host->hs_gear = UFS_HS_G2;
+	host->phy_gear = UFS_HS_G2;
 
 	return 0;
 
@@ -1296,14 +1315,96 @@ static void ufs_qcom_exit(struct ufs_hba *hba)
 	phy_exit(host->generic_phy);
 }
 
-static int ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(struct ufs_hba *hba,
-						       u32 clk_cycles)
+/**
+ * ufs_qcom_set_clk_40ns_cycles - Configure 40ns clk cycles
+ *
+ * @hba: host controller instance
+ * @cycles_in_1us: No of cycles in 1us to be configured
+ *
+ * Returns error if dme get/set configuration for 40ns fails
+ * and returns zero on success.
+ */
+static int ufs_qcom_set_clk_40ns_cycles(struct ufs_hba *hba,
+					u32 cycles_in_1us)
 {
+	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+	u32 cycles_in_40ns;
+	u32 reg;
 	int err;
-	u32 core_clk_ctrl_reg;
 
-	if (clk_cycles > DME_VS_CORE_CLK_CTRL_MAX_CORE_CLK_1US_CYCLES_MASK)
+	/*
+	 * UFS host controller V4.0.0 onwards needs to program
+	 * PA_VS_CORE_CLK_40NS_CYCLES attribute per programmed
+	 * frequency of unipro core clk of UFS host controller.
+	 */
+	if (host->hw_ver.major < 4)
+		return 0;
+
+	/*
+	 * Generic formulae for cycles_in_40ns = (freq_unipro/25) is not
+	 * applicable for all frequencies. For ex: ceil(37.5 MHz/25) will
+	 * be 2 and ceil(403 MHZ/25) will be 17 whereas Hardware
+	 * specification expect to be 16. Hence use exact hardware spec
+	 * mandated value for cycles_in_40ns instead of calculating using
+	 * generic formulae.
+	 */
+	switch (cycles_in_1us) {
+	case UNIPRO_CORE_CLK_FREQ_403_MHZ:
+		cycles_in_40ns = 16;
+		break;
+	case UNIPRO_CORE_CLK_FREQ_300_MHZ:
+		cycles_in_40ns = 12;
+		break;
+	case UNIPRO_CORE_CLK_FREQ_201_5_MHZ:
+		cycles_in_40ns = 8;
+		break;
+	case UNIPRO_CORE_CLK_FREQ_150_MHZ:
+		cycles_in_40ns = 6;
+		break;
+	case UNIPRO_CORE_CLK_FREQ_100_MHZ:
+		cycles_in_40ns = 4;
+		break;
+	case  UNIPRO_CORE_CLK_FREQ_75_MHZ:
+		cycles_in_40ns = 3;
+		break;
+	case UNIPRO_CORE_CLK_FREQ_37_5_MHZ:
+		cycles_in_40ns = 2;
+		break;
+	default:
+		dev_err(hba->dev, "UNIPRO clk freq %u MHz not supported\n",
+				cycles_in_1us);
 		return -EINVAL;
+	}
+
+	err = ufshcd_dme_get(hba, UIC_ARG_MIB(PA_VS_CORE_CLK_40NS_CYCLES), &reg);
+	if (err)
+		return err;
+
+	reg &= ~PA_VS_CORE_CLK_40NS_CYCLES_MASK;
+	reg |= cycles_in_40ns;
+
+	return ufshcd_dme_set(hba, UIC_ARG_MIB(PA_VS_CORE_CLK_40NS_CYCLES), reg);
+}
+
+static int ufs_qcom_set_core_clk_ctrl(struct ufs_hba *hba, bool is_scale_up)
+{
+	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+	struct list_head *head = &hba->clk_list_head;
+	struct ufs_clk_info *clki;
+	u32 cycles_in_1us;
+	u32 core_clk_ctrl_reg;
+	int err;
+
+	list_for_each_entry(clki, head, list) {
+		if (!IS_ERR_OR_NULL(clki->clk) &&
+			!strcmp(clki->name, "core_clk_unipro")) {
+			if (is_scale_up)
+				cycles_in_1us = ceil(clki->max_freq, (1000 * 1000));
+			else
+				cycles_in_1us = ceil(clk_get_rate(clki->clk), (1000 * 1000));
+			break;
+		}
+	}
 
 	err = ufshcd_dme_get(hba,
 			    UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL),
@@ -1311,32 +1412,58 @@ static int ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(struct ufs_hba *hba,
 	if (err)
 		return err;
 
-	core_clk_ctrl_reg &= ~DME_VS_CORE_CLK_CTRL_MAX_CORE_CLK_1US_CYCLES_MASK;
-	core_clk_ctrl_reg |= clk_cycles;
+	/* Bit mask is different for UFS host controller V4.0.0 onwards */
+	if (host->hw_ver.major >= 4) {
+		if (!FIELD_FIT(CLK_1US_CYCLES_MASK_V4, cycles_in_1us))
+			return -ERANGE;
+		core_clk_ctrl_reg &= ~CLK_1US_CYCLES_MASK_V4;
+		core_clk_ctrl_reg |= FIELD_PREP(CLK_1US_CYCLES_MASK_V4, cycles_in_1us);
+	} else {
+		if (!FIELD_FIT(CLK_1US_CYCLES_MASK, cycles_in_1us))
+			return -ERANGE;
+		core_clk_ctrl_reg &= ~CLK_1US_CYCLES_MASK;
+		core_clk_ctrl_reg |= FIELD_PREP(CLK_1US_CYCLES_MASK, cycles_in_1us);
+	}
 
 	/* Clear CORE_CLK_DIV_EN */
 	core_clk_ctrl_reg &= ~DME_VS_CORE_CLK_CTRL_CORE_CLK_DIV_EN_BIT;
 
-	return ufshcd_dme_set(hba,
+	err = ufshcd_dme_set(hba,
 			    UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL),
 			    core_clk_ctrl_reg);
-}
+	if (err)
+		return err;
 
-static int ufs_qcom_clk_scale_up_pre_change(struct ufs_hba *hba)
-{
-	/* nothing to do as of now */
-	return 0;
+	/* Configure unipro core clk 40ns attribute */
+	return ufs_qcom_set_clk_40ns_cycles(hba, cycles_in_1us);
 }
 
-static int ufs_qcom_clk_scale_up_post_change(struct ufs_hba *hba)
+static int ufs_qcom_clk_scale_up_pre_change(struct ufs_hba *hba)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+	struct ufs_pa_layer_attr *attr = &host->dev_req_params;
+	int ret;
 
 	if (!ufs_qcom_cap_qunipro(host))
 		return 0;
 
-	/* set unipro core clock cycles to 150 and clear clock divider */
-	return ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(hba, 150);
+	if (attr) {
+		ret = ufs_qcom_cfg_timers(hba, attr->gear_rx,
+					attr->pwr_rx, attr->hs_rate,
+					false, true);
+		if (ret) {
+			dev_err(hba->dev, "%s ufs cfg timer failed\n",
+						__func__);
+			return ret;
+		}
+	}
+	/* set unipro core clock attributes and clear clock divider */
+	return ufs_qcom_set_core_clk_ctrl(hba, true);
+}
+
+static int ufs_qcom_clk_scale_up_post_change(struct ufs_hba *hba)
+{
+	return 0;
 }
 
 static int ufs_qcom_clk_scale_down_pre_change(struct ufs_hba *hba)
@@ -1371,15 +1498,14 @@ static int ufs_qcom_clk_scale_down_post_change(struct ufs_hba *hba)
 	if (!ufs_qcom_cap_qunipro(host))
 		return 0;
 
-	/* set unipro core clock cycles to 75 and clear clock divider */
-	return ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(hba, 75);
+	/* set unipro core clock attributes and clear clock divider */
+	return ufs_qcom_set_core_clk_ctrl(hba, false);
 }
 
 static int ufs_qcom_clk_scale_notify(struct ufs_hba *hba,
 		bool scale_up, enum ufs_notify_change_status status)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
-	struct ufs_pa_layer_attr *dev_req_params = &host->dev_req_params;
 	int err = 0;
 
 	/* check the host controller state before sending hibern8 cmd */
@@ -1409,11 +1535,6 @@ static int ufs_qcom_clk_scale_notify(struct ufs_hba *hba,
 			return err;
 		}
 
-		ufs_qcom_cfg_timers(hba,
-				    dev_req_params->gear_rx,
-				    dev_req_params->pwr_rx,
-				    dev_req_params->hs_rate,
-				    false);
 		ufs_qcom_icc_update_bw(host);
 		ufshcd_uic_hibern8_exit(hba);
 	}
diff --git a/drivers/ufs/host/ufs-qcom.h b/drivers/ufs/host/ufs-qcom.h
index d6f8e74bd538..9950a0089475 100644
--- a/drivers/ufs/host/ufs-qcom.h
+++ b/drivers/ufs/host/ufs-qcom.h
@@ -129,8 +129,21 @@ enum {
 #define PA_VS_CONFIG_REG1	0x9000
 #define DME_VS_CORE_CLK_CTRL	0xD002
 /* bit and mask definitions for DME_VS_CORE_CLK_CTRL attribute */
-#define DME_VS_CORE_CLK_CTRL_CORE_CLK_DIV_EN_BIT		BIT(8)
-#define DME_VS_CORE_CLK_CTRL_MAX_CORE_CLK_1US_CYCLES_MASK	0xFF
+#define CLK_1US_CYCLES_MASK_V4				GENMASK(27, 16)
+#define CLK_1US_CYCLES_MASK				GENMASK(7, 0)
+#define DME_VS_CORE_CLK_CTRL_CORE_CLK_DIV_EN_BIT	BIT(8)
+#define PA_VS_CORE_CLK_40NS_CYCLES			0x9007
+#define PA_VS_CORE_CLK_40NS_CYCLES_MASK			GENMASK(6, 0)
+
+
+/* QCOM UFS host controller core clk frequencies */
+#define UNIPRO_CORE_CLK_FREQ_37_5_MHZ          38
+#define UNIPRO_CORE_CLK_FREQ_75_MHZ            75
+#define UNIPRO_CORE_CLK_FREQ_100_MHZ           100
+#define UNIPRO_CORE_CLK_FREQ_150_MHZ           150
+#define UNIPRO_CORE_CLK_FREQ_300_MHZ           300
+#define UNIPRO_CORE_CLK_FREQ_201_5_MHZ         202
+#define UNIPRO_CORE_CLK_FREQ_403_MHZ           403
 
 static inline void
 ufs_qcom_get_controller_revision(struct ufs_hba *hba,
@@ -227,7 +240,7 @@ struct ufs_qcom_host {
 
 	struct gpio_desc *device_reset;
 
-	u32 hs_gear;
+	u32 phy_gear;
 
 	bool esi_enabled;
 };
@@ -244,6 +257,7 @@ ufs_qcom_get_debug_reg_offset(struct ufs_qcom_host *host, u32 reg)
 #define ufs_qcom_is_link_off(hba) ufshcd_is_link_off(hba)
 #define ufs_qcom_is_link_active(hba) ufshcd_is_link_active(hba)
 #define ufs_qcom_is_link_hibern8(hba) ufshcd_is_link_hibern8(hba)
+#define ceil(freq, div) ((freq) % (div) == 0 ? ((freq)/(div)) : ((freq)/(div) + 1))
 
 int ufs_qcom_testbus_config(struct ufs_qcom_host *host);