ufs: ufs-amd-versal2: Add support for AMD UFS controller

Add UFS AMD platform support on top of the UFS DWC
and UFS platform driver. UFS AMD platform requires
some platform specific configurations like M-PHY/RMMI/UniPro
and vendor specific registers programming before doing the LINKSTARTUP.

Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu@amd.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20240920041651.18173-3-venkatesh.abbarapu@amd.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
diff --git a/drivers/ufs/ufs-amd-versal2.c b/drivers/ufs/ufs-amd-versal2.c
new file mode 100644
index 0000000..bfd844e
--- /dev/null
+++ b/drivers/ufs/ufs-amd-versal2.c
@@ -0,0 +1,501 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2024 Advanced Micro Devices, Inc.
+ */
+
+#include <clk.h>
+#include <dm.h>
+#include <ufs.h>
+#include <asm/io.h>
+#include <dm/device_compat.h>
+#include <zynqmp_firmware.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/time.h>
+#include <reset.h>
+
+#include "ufs.h"
+#include "ufshcd-dwc.h"
+#include "ufshci-dwc.h"
+
+#define VERSAL2_UFS_DEVICE_ID		4
+
+#define SRAM_CSR_INIT_DONE_MASK		BIT(0)
+#define SRAM_CSR_EXT_LD_DONE_MASK	BIT(1)
+#define SRAM_CSR_BYPASS_MASK		BIT(2)
+
+#define MPHY_FAST_RX_AFE_CAL		BIT(2)
+#define MPHY_FW_CALIB_CFG_VAL		BIT(8)
+
+#define TX_RX_CFG_RDY_MASK		GENMASK(3, 0)
+
+#define TIMEOUT_MICROSEC		1000000L
+
+#define IOCTL_UFS_TXRX_CFGRDY_GET	40
+#define IOCTL_UFS_SRAM_CSR_SEL		41
+
+#define PM_UFS_SRAM_CSR_WRITE		0
+#define PM_UFS_SRAM_CSR_READ		1
+
+struct ufs_versal2_priv {
+	struct ufs_hba *hba;
+	struct reset_ctl *rstc;
+	struct reset_ctl *rstphy;
+	u32 phy_mode;
+	u32 host_clk;
+	u32 pd_dev_id;
+	u8 attcompval0;
+	u8 attcompval1;
+	u8 ctlecompval0;
+	u8 ctlecompval1;
+};
+
+static int ufs_versal2_phy_reg_write(struct ufs_hba *hba, u32 addr, u32 val)
+{
+	static struct ufshcd_dme_attr_val phy_write_attrs[] = {
+		{ UIC_ARG_MIB(CBCREGADDRLSB), 0, DME_LOCAL },
+		{ UIC_ARG_MIB(CBCREGADDRMSB), 0, DME_LOCAL },
+		{ UIC_ARG_MIB(CBCREGWRLSB), 0, DME_LOCAL },
+		{ UIC_ARG_MIB(CBCREGWRMSB), 0, DME_LOCAL },
+		{ UIC_ARG_MIB(CBCREGRDWRSEL), 1, DME_LOCAL },
+		{ UIC_ARG_MIB(VS_MPHYCFGUPDT), 1, DME_LOCAL }
+	};
+
+	phy_write_attrs[0].mib_val = (u8)addr;
+	phy_write_attrs[1].mib_val = (u8)(addr >> 8);
+	phy_write_attrs[2].mib_val = (u8)val;
+	phy_write_attrs[3].mib_val = (u8)(val >> 8);
+
+	return ufshcd_dwc_dme_set_attrs(hba, phy_write_attrs, ARRAY_SIZE(phy_write_attrs));
+}
+
+static int ufs_versal2_phy_reg_read(struct ufs_hba *hba, u32 addr, u32 *val)
+{
+	u32 mib_val;
+	int ret;
+	static struct ufshcd_dme_attr_val phy_read_attrs[] = {
+		{ UIC_ARG_MIB(CBCREGADDRLSB), 0, DME_LOCAL },
+		{ UIC_ARG_MIB(CBCREGADDRMSB), 0, DME_LOCAL },
+		{ UIC_ARG_MIB(CBCREGRDWRSEL), 0, DME_LOCAL },
+		{ UIC_ARG_MIB(VS_MPHYCFGUPDT), 1, DME_LOCAL }
+	};
+
+	phy_read_attrs[0].mib_val = (u8)addr;
+	phy_read_attrs[1].mib_val = (u8)(addr >> 8);
+
+	ret = ufshcd_dwc_dme_set_attrs(hba, phy_read_attrs, ARRAY_SIZE(phy_read_attrs));
+	if (ret)
+		return ret;
+
+	ret = ufshcd_dme_get(hba, UIC_ARG_MIB(CBCREGRDLSB), &mib_val);
+	if (ret)
+		return ret;
+
+	*val = mib_val;
+	ret = ufshcd_dme_get(hba, UIC_ARG_MIB(CBCREGRDMSB), &mib_val);
+	if (ret)
+		return ret;
+
+	*val |= (mib_val << 8);
+
+	return 0;
+}
+
+int versal2_pm_ufs_get_txrx_cfgrdy(u32 node_id, u32 *value)
+{
+	u32 ret_payload[PAYLOAD_ARG_CNT];
+	int ret;
+
+	if (!value)
+		return -EINVAL;
+
+	ret = xilinx_pm_request(PM_IOCTL, node_id, IOCTL_UFS_TXRX_CFGRDY_GET,
+				0, 0, ret_payload);
+	*value = ret_payload[1];
+
+	return ret;
+}
+
+int versal2_pm_ufs_sram_csr_sel(u32 node_id, u32 type, u32 *value)
+{
+	u32 ret_payload[PAYLOAD_ARG_CNT];
+	int ret;
+
+	if (!value)
+		return -EINVAL;
+
+	if (type == PM_UFS_SRAM_CSR_READ) {
+		ret =  xilinx_pm_request(PM_IOCTL, node_id, IOCTL_UFS_SRAM_CSR_SEL,
+					 type, 0, ret_payload);
+		*value = ret_payload[1];
+	} else {
+		ret = xilinx_pm_request(PM_IOCTL, node_id, IOCTL_UFS_SRAM_CSR_SEL,
+					type, *value, 0);
+	}
+
+	return ret;
+}
+
+static int ufs_versal2_enable_phy(struct ufs_hba *hba)
+{
+	u32 offset, reg;
+	int ret;
+
+	ret = ufshcd_dme_set(hba, UIC_ARG_MIB(VS_MPHYDISABLE), 0);
+	if (ret)
+		return ret;
+
+	ret = ufshcd_dme_set(hba, UIC_ARG_MIB(VS_MPHYCFGUPDT), 1);
+	if (ret)
+		return ret;
+
+	/* Check Tx/Rx FSM states */
+	for (offset = 0; offset < 2; offset++) {
+		u32 time_left, mibsel;
+
+		time_left = TIMEOUT_MICROSEC;
+		mibsel = UIC_ARG_MIB_SEL(MTX_FSM_STATE, UIC_ARG_MPHY_TX_GEN_SEL_INDEX(offset));
+		do {
+			ret = ufshcd_dme_get(hba, mibsel, &reg);
+			if (ret)
+				return ret;
+
+			if (reg == TX_STATE_HIBERN8 || reg == TX_STATE_SLEEP ||
+			    reg == TX_STATE_LSBURST)
+				break;
+
+			time_left--;
+			mdelay(5);
+		} while (time_left);
+
+		if (!time_left) {
+			dev_err(hba->dev, "Invalid Tx FSM state.\n");
+			return -ETIMEDOUT;
+		}
+
+		time_left = TIMEOUT_MICROSEC;
+		mibsel = UIC_ARG_MIB_SEL(MRX_FSM_STATE, UIC_ARG_MPHY_RX_GEN_SEL_INDEX(offset));
+		do {
+			ret = ufshcd_dme_get(hba, mibsel, &reg);
+			if (ret)
+				return ret;
+
+			if (reg == RX_STATE_HIBERN8 || reg == RX_STATE_SLEEP ||
+			    reg == RX_STATE_LSBURST)
+				break;
+
+			time_left--;
+			mdelay(5);
+		} while (time_left);
+
+		if (!time_left) {
+			dev_err(hba->dev, "Invalid Rx FSM state.\n");
+			return -ETIMEDOUT;
+		}
+	}
+
+	return 0;
+}
+
+static int ufs_versal2_setup_phy(struct ufs_hba *hba)
+{
+	struct ufs_versal2_priv *priv = dev_get_priv(hba->dev);
+	int ret;
+	u32 reg;
+
+	/* Bypass RX-AFE offset calibrations (ATT/CTLE) */
+	ret = ufs_versal2_phy_reg_read(hba, FAST_FLAGS(0), &reg);
+	if (ret)
+		return ret;
+
+	reg |= MPHY_FAST_RX_AFE_CAL;
+	ret = ufs_versal2_phy_reg_write(hba, FAST_FLAGS(0), reg);
+	if (ret)
+		return ret;
+
+	ret = ufs_versal2_phy_reg_read(hba, FAST_FLAGS(1), &reg);
+	if (ret)
+		return ret;
+
+	reg |= MPHY_FAST_RX_AFE_CAL;
+	ret = ufs_versal2_phy_reg_write(hba, FAST_FLAGS(1), reg);
+	if (ret)
+		return ret;
+
+	/* Program ATT and CTLE compensation values */
+	if (priv->attcompval0) {
+		ret = ufs_versal2_phy_reg_write(hba, RX_AFE_ATT_IDAC(0), priv->attcompval0);
+		if (ret)
+			return ret;
+	}
+
+	if (priv->attcompval1) {
+		ret = ufs_versal2_phy_reg_write(hba, RX_AFE_ATT_IDAC(1), priv->attcompval1);
+		if (ret)
+			return ret;
+	}
+
+	if (priv->ctlecompval0) {
+		ret = ufs_versal2_phy_reg_write(hba, RX_AFE_CTLE_IDAC(0), priv->ctlecompval0);
+		if (ret)
+			return ret;
+	}
+
+	if (priv->ctlecompval1) {
+		ret = ufs_versal2_phy_reg_write(hba, RX_AFE_CTLE_IDAC(1), priv->ctlecompval1);
+		if (ret)
+			return ret;
+	}
+
+	ret = ufs_versal2_phy_reg_read(hba, FW_CALIB_CCFG(0), &reg);
+	if (ret)
+		return ret;
+
+	reg |= MPHY_FW_CALIB_CFG_VAL;
+	ret = ufs_versal2_phy_reg_write(hba, FW_CALIB_CCFG(0), reg);
+	if (ret)
+		return ret;
+
+	ret = ufs_versal2_phy_reg_read(hba, FW_CALIB_CCFG(1), &reg);
+	if (ret)
+		return ret;
+
+	reg |= MPHY_FW_CALIB_CFG_VAL;
+	return ufs_versal2_phy_reg_write(hba, FW_CALIB_CCFG(1), reg);
+}
+
+static int ufs_versal2_phy_init(struct ufs_hba *hba)
+{
+	struct ufs_versal2_priv *priv = dev_get_priv(hba->dev);
+	u32 reg, time_left;
+	int ret;
+	static const struct ufshcd_dme_attr_val rmmi_attrs[] = {
+		{ UIC_ARG_MIB(CBREFCLKCTRL2), CBREFREFCLK_GATE_OVR_EN, DME_LOCAL },
+		{ UIC_ARG_MIB(CBCRCTRL), 1, DME_LOCAL },
+		{ UIC_ARG_MIB(CBC10DIRECTCONF2), 1, DME_LOCAL },
+		{ UIC_ARG_MIB(VS_MPHYCFGUPDT), 1, DME_LOCAL }
+	};
+
+	/* Wait for Tx/Rx config_rdy */
+	time_left = TIMEOUT_MICROSEC;
+	do {
+		time_left--;
+		ret = versal2_pm_ufs_get_txrx_cfgrdy(priv->pd_dev_id, &reg);
+		if (ret)
+			return ret;
+
+		reg &= TX_RX_CFG_RDY_MASK;
+		if (!reg)
+			break;
+
+		mdelay(5);
+	} while (time_left);
+
+	if (!time_left) {
+		dev_err(hba->dev, "Tx/Rx configuration signal busy.\n");
+		return -ETIMEDOUT;
+	}
+
+	ret = ufshcd_dwc_dme_set_attrs(hba, rmmi_attrs, ARRAY_SIZE(rmmi_attrs));
+	if (ret)
+		return ret;
+
+	/* DeAssert PHY reset */
+	ret = reset_deassert(priv->rstphy);
+	if (ret) {
+		dev_err(hba->dev, "ufsphy reset deassert failed\n");
+		return ret;
+	}
+
+	/* Wait for SRAM init done */
+	time_left = TIMEOUT_MICROSEC;
+	do {
+		time_left--;
+		ret = versal2_pm_ufs_sram_csr_sel(priv->pd_dev_id,
+						  PM_UFS_SRAM_CSR_READ, &reg);
+		if (ret)
+			return ret;
+
+		reg &= SRAM_CSR_INIT_DONE_MASK;
+		if (reg)
+			break;
+
+		mdelay(5);
+	} while (time_left);
+
+	if (!time_left) {
+		dev_err(hba->dev, "SRAM initialization failed.\n");
+		return -ETIMEDOUT;
+	}
+
+	ret = ufs_versal2_setup_phy(hba);
+	if (ret)
+		return ret;
+
+	return ufs_versal2_enable_phy(hba);
+}
+
+static int ufs_versal2_init(struct ufs_hba *hba)
+{
+	struct ufs_versal2_priv *priv = dev_get_priv(hba->dev);
+	struct clk clk;
+	unsigned long core_clk_rate = 0;
+	int ret = 0;
+
+	priv->phy_mode = UFSHCD_DWC_PHY_MODE_ROM;
+	priv->pd_dev_id = VERSAL2_UFS_DEVICE_ID;
+
+	ret = clk_get_by_name(hba->dev, "core_clk", &clk);
+	if (ret) {
+		dev_err(hba->dev, "failed to get core_clk clock\n");
+		return ret;
+	}
+
+	core_clk_rate = clk_get_rate(&clk);
+	if (IS_ERR_VALUE(core_clk_rate)) {
+		dev_err(hba->dev, "%s: unable to find core_clk rate\n",
+			__func__);
+		return core_clk_rate;
+	}
+	priv->host_clk = core_clk_rate;
+
+	priv->rstc = devm_reset_control_get(hba->dev, "ufshc-rst");
+	if (IS_ERR(priv->rstc)) {
+		dev_err(hba->dev, "failed to get reset ctl: ufshc-rst\n");
+		return PTR_ERR(priv->rstc);
+	}
+	priv->rstphy = devm_reset_control_get(hba->dev, "ufsphy-rst");
+	if (IS_ERR(priv->rstphy)) {
+		dev_err(hba->dev, "failed to get reset ctl: ufsphy-rst\n");
+		return PTR_ERR(priv->rstphy);
+	}
+
+	return ret;
+}
+
+static int ufs_versal2_hce_enable_notify(struct ufs_hba *hba,
+					 enum ufs_notify_change_status status)
+{
+	struct ufs_versal2_priv *priv = dev_get_priv(hba->dev);
+	u32 sram_csr;
+	int ret;
+
+	switch (status) {
+	case PRE_CHANGE:
+		/* Assert RST_UFS Reset for UFS block in PMX_IOU */
+		ret = reset_assert(priv->rstc);
+		if (ret) {
+			dev_err(hba->dev, "ufshc reset assert failed, err = %d\n", ret);
+			return ret;
+		}
+
+		/* Assert PHY reset */
+		ret = reset_assert(priv->rstphy);
+		if (ret) {
+			dev_err(hba->dev, "ufsphy reset assert failed, err = %d\n", ret);
+			return ret;
+		}
+
+		ret = versal2_pm_ufs_sram_csr_sel(priv->pd_dev_id,
+						  PM_UFS_SRAM_CSR_READ, &sram_csr);
+		if (ret)
+			return ret;
+
+		if (!priv->phy_mode) {
+			sram_csr &= ~SRAM_CSR_EXT_LD_DONE_MASK;
+			sram_csr |= SRAM_CSR_BYPASS_MASK;
+		} else {
+			dev_err(hba->dev, "Invalid phy-mode %d.\n", priv->phy_mode);
+			return -EINVAL;
+		}
+
+		ret = versal2_pm_ufs_sram_csr_sel(priv->pd_dev_id,
+						  PM_UFS_SRAM_CSR_WRITE, &sram_csr);
+		if (ret)
+			return ret;
+
+		/* De Assert RST_UFS Reset for UFS block in PMX_IOU */
+		ret = reset_deassert(priv->rstc);
+		if (ret)
+			dev_err(hba->dev, "ufshc reset deassert failed, err = %d\n", ret);
+
+		break;
+	case POST_CHANGE:
+		ret = ufs_versal2_phy_init(hba);
+		if (ret)
+			dev_err(hba->dev, "Phy init failed (%d)\n", ret);
+
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static int ufs_versal2_link_startup_notify(struct ufs_hba *hba,
+					   enum ufs_notify_change_status status)
+{
+	struct ufs_versal2_priv *priv = dev_get_priv(hba->dev);
+	int ret = 0;
+
+	switch (status) {
+	case PRE_CHANGE:
+		if (priv->host_clk) {
+			u32 core_clk_div = priv->host_clk / TIMEOUT_MICROSEC;
+
+			ufshcd_writel(hba, core_clk_div, DWC_UFS_REG_HCLKDIV);
+		}
+		break;
+	case POST_CHANGE:
+		ret = ufshcd_dwc_link_startup_notify(hba, status);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static struct ufs_hba_ops ufs_versal2_hba_ops = {
+	.init = ufs_versal2_init,
+	.link_startup_notify = ufs_versal2_link_startup_notify,
+	.hce_enable_notify = ufs_versal2_hce_enable_notify,
+};
+
+static int ufs_versal2_probe(struct udevice *dev)
+{
+	int ret;
+
+	/* Perform generic probe */
+	ret = ufshcd_probe(dev, &ufs_versal2_hba_ops);
+	if (ret)
+		dev_err(dev, "ufshcd_probe() failed %d\n", ret);
+
+	return ret;
+}
+
+static int ufs_versal2_bind(struct udevice *dev)
+{
+	struct udevice *scsi_dev;
+
+	return ufs_scsi_bind(dev, &scsi_dev);
+}
+
+static const struct udevice_id ufs_versal2_ids[] = {
+	{
+		.compatible = "amd,versal2-ufs",
+	},
+	{},
+};
+
+U_BOOT_DRIVER(ufs_versal2_pltfm) = {
+	.name           = "ufs-versal2-pltfm",
+	.id             = UCLASS_UFS,
+	.of_match       = ufs_versal2_ids,
+	.probe          = ufs_versal2_probe,
+	.bind           = ufs_versal2_bind,
+};