[PATCH 5/6] phy: phy-mtk-tphy: add support efuse setting

[Chunfeng Yun]

Due to some SoCs have a bit shift issue that will drop a bit for usb3
phy or pcie phy, fix it by adding software efuse reading and setting,
but only support it optionally for versoin 2/3.

Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
---
 drivers/phy/mediatek/phy-mtk-tphy.c | 162 ++++++++++++++++++++++++++++
 1 file changed, 162 insertions(+)

diff --git a/drivers/phy/mediatek/phy-mtk-tphy.c b/drivers/phy/mediatek/phy-mtk-tphy.c
index cdcef865fe9e..3b5b1c266595 100644
--- a/drivers/phy/mediatek/phy-mtk-tphy.c
+++ b/drivers/phy/mediatek/phy-mtk-tphy.c
@@ -12,6 +12,7 @@
 #include <linux/iopoll.h>
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
+#include <linux/nvmem-consumer.h>
 #include <linux/of_address.h>
 #include <linux/of_device.h>
 #include <linux/phy/phy.h>
@@ -41,6 +42,9 @@
 #define SSUSB_SIFSLV_V2_U3PHYD		0x200
 #define SSUSB_SIFSLV_V2_U3PHYA		0x400
 
+#define U3P_MISC_REG1		0x04
+#define MR1_EFUSE_AUTO_LOAD_DIS		BIT(6)
+
 #define U3P_USBPHYACR0		0x000
 #define PA0_RG_U2PLL_FORCE_ON		BIT(15)
 #define PA0_USB20_PLL_PREDIV		GENMASK(7, 6)
@@ -133,6 +137,8 @@
 #define P3C_RG_SWRST_U3_PHYD_FORCE_EN	BIT(24)
 
 #define U3P_U3_PHYA_REG0	0x000
+#define P3A_RG_IEXT_INTR		GENMASK(15, 10)
+#define P3A_RG_IEXT_INTR_VAL(x)		((0x3f & (x)) << 10)
 #define P3A_RG_CLKDRV_OFF		GENMASK(3, 2)
 #define P3A_RG_CLKDRV_OFF_VAL(x)	((0x3 & (x)) << 2)
 
@@ -187,6 +193,19 @@
 #define P3D_RG_FWAKE_TH		GENMASK(21, 16)
 #define P3D_RG_FWAKE_TH_VAL(x)	((0x3f & (x)) << 16)
 
+#define U3P_U3_PHYD_IMPCAL0		0x010
+#define P3D_RG_FORCE_TX_IMPEL		BIT(31)
+#define P3D_RG_TX_IMPEL			GENMASK(28, 24)
+#define P3D_RG_TX_IMPEL_VAL(x)		((0x1f & (x)) << 24)
+
+#define U3P_U3_PHYD_IMPCAL1		0x014
+#define P3D_RG_FORCE_RX_IMPEL		BIT(31)
+#define P3D_RG_RX_IMPEL			GENMASK(28, 24)
+#define P3D_RG_RX_IMPEL_VAL(x)		((0x1f & (x)) << 24)
+
+#define U3P_U3_PHYD_RSV			0x054
+#define P3D_RG_EFUSE_AUTO_LOAD_DIS	BIT(12)
+
 #define U3P_U3_PHYD_CDR1		0x05c
 #define P3D_RG_CDR_BIR_LTD1		GENMASK(28, 24)
 #define P3D_RG_CDR_BIR_LTD1_VAL(x)	((0x1f & (x)) << 24)
@@ -307,6 +326,11 @@ struct mtk_phy_pdata {
 	 * 48M PLL, fix it by switching PLL to 26M from default 48M
 	 */
 	bool sw_pll_48m_to_26m;
+	/*
+	 * Some SoCs (e.g. mt8195) drop a bit when use auto load efuse,
+	 * support sw way, also support it for v2/v3 optionally.
+	 */
+	bool sw_efuse_supported;
 	enum mtk_phy_version version;
 };
 
@@ -336,6 +360,10 @@ struct mtk_phy_instance {
 	struct regmap *type_sw;
 	u32 type_sw_reg;
 	u32 type_sw_index;
+	u32 efuse_sw_en;
+	u32 efuse_intr;
+	u32 efuse_tx_imp;
+	u32 efuse_rx_imp;
 	int eye_src;
 	int eye_vrt;
 	int eye_term;
@@ -1040,6 +1068,130 @@ static int phy_type_set(struct mtk_phy_instance *instance)
 	return 0;
 }
 
+static int phy_efuse_get(struct mtk_tphy *tphy, struct mtk_phy_instance *instance)
+{
+	struct device *dev = &instance->phy->dev;
+	int ret = 0;
+
+	/* tphy v1 doesn't support sw efuse, skip it */
+	if (!tphy->pdata->sw_efuse_supported) {
+		instance->efuse_sw_en = 0;
+		return 0;
+	}
+
+	/* software efuse is optional */
+	instance->efuse_sw_en = device_property_read_bool(dev, "nvmem-cells");
+	if (!instance->efuse_sw_en)
+		return 0;
+
+	switch (instance->type) {
+	case PHY_TYPE_USB2:
+		ret = nvmem_cell_read_variable_le_u32(dev, "intr", &instance->efuse_intr);
+		if (ret) {
+			dev_err(dev, "fail to get u2 intr efuse, %d\n", ret);
+			break;
+		}
+
+		/* no efuse, ignore it */
+		if (!instance->efuse_intr) {
+			dev_warn(dev, "no u2 intr efuse, but dts enable it\n");
+			instance->efuse_sw_en = 0;
+			break;
+		}
+
+		dev_info(dev, "u2 efuse - intr %x\n", instance->efuse_intr);
+		break;
+	case PHY_TYPE_USB3:
+	case PHY_TYPE_PCIE:
+		ret = nvmem_cell_read_variable_le_u32(dev, "intr", &instance->efuse_intr);
+		if (ret) {
+			dev_err(dev, "fail to get u3 intr efuse, %d\n", ret);
+			break;
+		}
+
+		ret = nvmem_cell_read_variable_le_u32(dev, "rx_imp", &instance->efuse_rx_imp);
+		if (ret) {
+			dev_err(dev, "fail to get u3 rx_imp efuse, %d\n", ret);
+			break;
+		}
+
+		ret = nvmem_cell_read_variable_le_u32(dev, "tx_imp", &instance->efuse_tx_imp);
+		if (ret) {
+			dev_err(dev, "fail to get u3 tx_imp efuse, %d\n", ret);
+			break;
+		}
+
+		/* no efuse, ignore it */
+		if (!instance->efuse_intr &&
+		    !instance->efuse_rx_imp &&
+		    !instance->efuse_rx_imp) {
+			dev_warn(dev, "no u3 intr efuse, but dts enable it\n");
+			instance->efuse_sw_en = 0;
+			break;
+		}
+
+		dev_info(dev, "u3 efuse - intr %x, rx_imp %x, tx_imp %x\n",
+			 instance->efuse_intr, instance->efuse_rx_imp,
+			 instance->efuse_tx_imp);
+		break;
+	default:
+		dev_err(dev, "no sw efuse for type %d\n", instance->type);
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static void phy_efuse_set(struct mtk_phy_instance *instance)
+{
+	struct device *dev = &instance->phy->dev;
+	struct u2phy_banks *u2_banks = &instance->u2_banks;
+	struct u3phy_banks *u3_banks = &instance->u3_banks;
+	u32 tmp;
+
+	if (!instance->efuse_sw_en)
+		return;
+
+	switch (instance->type) {
+	case PHY_TYPE_USB2:
+		tmp = readl(u2_banks->misc + U3P_MISC_REG1);
+		tmp |= MR1_EFUSE_AUTO_LOAD_DIS;
+		writel(tmp, u2_banks->misc + U3P_MISC_REG1);
+
+		tmp = readl(u2_banks->com + U3P_USBPHYACR1);
+		tmp &= ~PA1_RG_INTR_CAL;
+		tmp |= PA1_RG_INTR_CAL_VAL(instance->efuse_intr);
+		writel(tmp, u2_banks->com + U3P_USBPHYACR1);
+		break;
+	case PHY_TYPE_USB3:
+	case PHY_TYPE_PCIE:
+		tmp = readl(u3_banks->phyd + U3P_U3_PHYD_RSV);
+		tmp |= P3D_RG_EFUSE_AUTO_LOAD_DIS;
+		writel(tmp, u3_banks->phyd + U3P_U3_PHYD_RSV);
+
+		tmp = readl(u3_banks->phyd + U3P_U3_PHYD_IMPCAL0);
+		tmp &= ~P3D_RG_TX_IMPEL;
+		tmp |= P3D_RG_TX_IMPEL_VAL(instance->efuse_tx_imp);
+		tmp |= P3D_RG_FORCE_TX_IMPEL;
+		writel(tmp, u3_banks->phyd + U3P_U3_PHYD_IMPCAL0);
+
+		tmp = readl(u3_banks->phyd + U3P_U3_PHYD_IMPCAL1);
+		tmp &= ~P3D_RG_RX_IMPEL;
+		tmp |= P3D_RG_RX_IMPEL_VAL(instance->efuse_rx_imp);
+		tmp |= P3D_RG_FORCE_RX_IMPEL;
+		writel(tmp, u3_banks->phyd + U3P_U3_PHYD_IMPCAL1);
+
+		tmp = readl(u3_banks->phya + U3P_U3_PHYA_REG0);
+		tmp &= ~P3A_RG_IEXT_INTR;
+		tmp |= P3A_RG_IEXT_INTR_VAL(instance->efuse_intr);
+		writel(tmp, u3_banks->phya + U3P_U3_PHYA_REG0);
+		break;
+	default:
+		dev_warn(dev, "no sw efuse for type %d\n", instance->type);
+		break;
+	}
+}
+
 static int mtk_phy_init(struct phy *phy)
 {
 	struct mtk_phy_instance *instance = phy_get_drvdata(phy);
@@ -1050,6 +1202,8 @@ static int mtk_phy_init(struct phy *phy)
 	if (ret)
 		return ret;
 
+	phy_efuse_set(instance);
+
 	switch (instance->type) {
 	case PHY_TYPE_USB2:
 		u2_phy_instance_init(tphy, instance);
@@ -1134,6 +1288,7 @@ static struct phy *mtk_phy_xlate(struct device *dev,
 	struct mtk_phy_instance *instance = NULL;
 	struct device_node *phy_np = args->np;
 	int index;
+	int ret;
 
 	if (args->args_count != 1) {
 		dev_err(dev, "invalid number of cells in 'phy' property\n");
@@ -1174,6 +1329,10 @@ static struct phy *mtk_phy_xlate(struct device *dev,
 		return ERR_PTR(-EINVAL);
 	}
 
+	ret = phy_efuse_get(tphy, instance);
+	if (ret)
+		return ERR_PTR(ret);
+
 	phy_parse_property(tphy, instance);
 	phy_type_set(instance);
 
@@ -1196,10 +1355,12 @@ static const struct mtk_phy_pdata tphy_v1_pdata = {
 
 static const struct mtk_phy_pdata tphy_v2_pdata = {
 	.avoid_rx_sen_degradation = false,
+	.sw_efuse_supported = true,
 	.version = MTK_PHY_V2,
 };
 
 static const struct mtk_phy_pdata tphy_v3_pdata = {
+	.sw_efuse_supported = true,
 	.version = MTK_PHY_V3,
 };
 
@@ -1210,6 +1371,7 @@ static const struct mtk_phy_pdata mt8173_pdata = {
 
 static const struct mtk_phy_pdata mt8195_pdata = {
 	.sw_pll_48m_to_26m = true,
+	.sw_efuse_supported = true,
 	.version = MTK_PHY_V3,
 };
 
-- 
2.18.0