1 files changed, 366 insertions, 0 deletions

diff --git a/drivers/phy/samsung/phy-samsung-ufs.c b/drivers/phy/samsung/phy-samsung-ufs.c
new file mode 100644
index 000000000000..9832599a0283
--- /dev/null
+++ b/drivers/phy/samsung/phy-samsung-ufs.c
@@ -0,0 +1,366 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * UFS PHY driver for Samsung SoC
+ *
+ * Copyright (C) 2020 Samsung Electronics Co., Ltd.
+ * Author: Seungwon Jeon <essuuj@gmail.com>
+ * Author: Alim Akhtar <alim.akhtar@samsung.com>
+ *
+ */
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include "phy-samsung-ufs.h"
+
+#define for_each_phy_lane(phy, i) \
+	for (i = 0; i < (phy)->lane_cnt; i++)
+#define for_each_phy_cfg(cfg) \
+	for (; (cfg)->id; (cfg)++)
+
+#define PHY_DEF_LANE_CNT	1
+
+static void samsung_ufs_phy_config(struct samsung_ufs_phy *phy,
+				   const struct samsung_ufs_phy_cfg *cfg,
+				   u8 lane)
+{
+	enum {LANE_0, LANE_1}; /* lane index */
+
+	switch (lane) {
+	case LANE_0:
+		writel(cfg->val, (phy)->reg_pma + cfg->off_0);
+		break;
+	case LANE_1:
+		if (cfg->id == PHY_TRSV_BLK)
+			writel(cfg->val, (phy)->reg_pma + cfg->off_1);
+		break;
+	}
+}
+
+static int samsung_ufs_phy_wait_for_lock_acq(struct phy *phy)
+{
+	struct samsung_ufs_phy *ufs_phy = get_samsung_ufs_phy(phy);
+	const unsigned int timeout_us = 100000;
+	const unsigned int sleep_us = 10;
+	u32 val;
+	int err;
+
+	err = readl_poll_timeout(
+			ufs_phy->reg_pma + PHY_APB_ADDR(PHY_PLL_LOCK_STATUS),
+			val, (val & PHY_PLL_LOCK_BIT), sleep_us, timeout_us);
+	if (err) {
+		dev_err(ufs_phy->dev,
+			"failed to get phy pll lock acquisition %d\n", err);
+		goto out;
+	}
+
+	err = readl_poll_timeout(
+			ufs_phy->reg_pma + PHY_APB_ADDR(PHY_CDR_LOCK_STATUS),
+			val, (val & PHY_CDR_LOCK_BIT), sleep_us, timeout_us);
+	if (err)
+		dev_err(ufs_phy->dev,
+			"failed to get phy cdr lock acquisition %d\n", err);
+out:
+	return err;
+}
+
+static int samsung_ufs_phy_calibrate(struct phy *phy)
+{
+	struct samsung_ufs_phy *ufs_phy = get_samsung_ufs_phy(phy);
+	struct samsung_ufs_phy_cfg **cfgs = ufs_phy->cfg;
+	const struct samsung_ufs_phy_cfg *cfg;
+	int err = 0;
+	int i;
+
+	if (unlikely(ufs_phy->ufs_phy_state < CFG_PRE_INIT ||
+		     ufs_phy->ufs_phy_state >= CFG_TAG_MAX)) {
+		dev_err(ufs_phy->dev, "invalid phy config index %d\n", ufs_phy->ufs_phy_state);
+		return -EINVAL;
+	}
+
+	cfg = cfgs[ufs_phy->ufs_phy_state];
+	if (!cfg)
+		goto out;
+
+	for_each_phy_cfg(cfg) {
+		for_each_phy_lane(ufs_phy, i) {
+			samsung_ufs_phy_config(ufs_phy, cfg, i);
+		}
+	}
+
+	if (ufs_phy->ufs_phy_state == CFG_POST_PWR_HS)
+		err = samsung_ufs_phy_wait_for_lock_acq(phy);
+
+	/**
+	 * In Samsung ufshci, PHY need to be calibrated at different
+	 * stages / state mainly before Linkstartup, after Linkstartup,
+	 * before power mode change and after power mode change.
+	 * Below state machine to make sure to calibrate PHY in each
+	 * state. Here after configuring PHY in a given state, will
+	 * change the state to next state so that next state phy
+	 * calibration value can be programed
+	 */
+out:
+	switch (ufs_phy->ufs_phy_state) {
+	case CFG_PRE_INIT:
+		ufs_phy->ufs_phy_state = CFG_POST_INIT;
+		break;
+	case CFG_POST_INIT:
+		ufs_phy->ufs_phy_state = CFG_PRE_PWR_HS;
+		break;
+	case CFG_PRE_PWR_HS:
+		ufs_phy->ufs_phy_state = CFG_POST_PWR_HS;
+		break;
+	case CFG_POST_PWR_HS:
+		/* Change back to INIT state */
+		ufs_phy->ufs_phy_state = CFG_PRE_INIT;
+		break;
+	default:
+		dev_err(ufs_phy->dev, "wrong state for phy calibration\n");
+	}
+
+	return err;
+}
+
+static int samsung_ufs_phy_symbol_clk_init(struct samsung_ufs_phy *phy)
+{
+	int ret;
+
+	phy->tx0_symbol_clk = devm_clk_get(phy->dev, "tx0_symbol_clk");
+	if (IS_ERR(phy->tx0_symbol_clk)) {
+		dev_err(phy->dev, "failed to get tx0_symbol_clk clock\n");
+		return PTR_ERR(phy->tx0_symbol_clk);
+	}
+
+	phy->rx0_symbol_clk = devm_clk_get(phy->dev, "rx0_symbol_clk");
+	if (IS_ERR(phy->rx0_symbol_clk)) {
+		dev_err(phy->dev, "failed to get rx0_symbol_clk clock\n");
+		return PTR_ERR(phy->rx0_symbol_clk);
+	}
+
+	phy->rx1_symbol_clk = devm_clk_get(phy->dev, "rx1_symbol_clk");
+	if (IS_ERR(phy->rx1_symbol_clk)) {
+		dev_err(phy->dev, "failed to get rx1_symbol_clk clock\n");
+		return PTR_ERR(phy->rx1_symbol_clk);
+	}
+
+	ret = clk_prepare_enable(phy->tx0_symbol_clk);
+	if (ret) {
+		dev_err(phy->dev, "%s: tx0_symbol_clk enable failed %d\n", __func__, ret);
+		goto out;
+	}
+
+	ret = clk_prepare_enable(phy->rx0_symbol_clk);
+	if (ret) {
+		dev_err(phy->dev, "%s: rx0_symbol_clk enable failed %d\n", __func__, ret);
+		goto out_disable_tx0_clk;
+	}
+
+	ret = clk_prepare_enable(phy->rx1_symbol_clk);
+	if (ret) {
+		dev_err(phy->dev, "%s: rx1_symbol_clk enable failed %d\n", __func__, ret);
+		goto out_disable_rx0_clk;
+	}
+
+	return 0;
+
+out_disable_rx0_clk:
+	clk_disable_unprepare(phy->rx0_symbol_clk);
+out_disable_tx0_clk:
+	clk_disable_unprepare(phy->tx0_symbol_clk);
+out:
+	return ret;
+}
+
+static int samsung_ufs_phy_clks_init(struct samsung_ufs_phy *phy)
+{
+	int ret;
+
+	phy->ref_clk = devm_clk_get(phy->dev, "ref_clk");
+	if (IS_ERR(phy->ref_clk))
+		dev_err(phy->dev, "failed to get ref_clk clock\n");
+
+	ret = clk_prepare_enable(phy->ref_clk);
+	if (ret) {
+		dev_err(phy->dev, "%s: ref_clk enable failed %d\n", __func__, ret);
+		return ret;
+	}
+
+	dev_dbg(phy->dev, "UFS MPHY ref_clk_rate = %ld\n", clk_get_rate(phy->ref_clk));
+
+	return 0;
+}
+
+static int samsung_ufs_phy_init(struct phy *phy)
+{
+	struct samsung_ufs_phy *ss_phy = get_samsung_ufs_phy(phy);
+	int ret;
+
+	ss_phy->lane_cnt = phy->attrs.bus_width;
+	ss_phy->ufs_phy_state = CFG_PRE_INIT;
+
+	if (ss_phy->drvdata->has_symbol_clk) {
+		ret = samsung_ufs_phy_symbol_clk_init(ss_phy);
+		if (ret)
+			dev_err(ss_phy->dev, "failed to set ufs phy symbol clocks\n");
+	}
+
+	ret = samsung_ufs_phy_clks_init(ss_phy);
+	if (ret)
+		dev_err(ss_phy->dev, "failed to set ufs phy clocks\n");
+
+	ret = samsung_ufs_phy_calibrate(phy);
+	if (ret)
+		dev_err(ss_phy->dev, "ufs phy calibration failed\n");
+
+	return ret;
+}
+
+static int samsung_ufs_phy_power_on(struct phy *phy)
+{
+	struct samsung_ufs_phy *ss_phy = get_samsung_ufs_phy(phy);
+
+	samsung_ufs_phy_ctrl_isol(ss_phy, false);
+	return 0;
+}
+
+static int samsung_ufs_phy_power_off(struct phy *phy)
+{
+	struct samsung_ufs_phy *ss_phy = get_samsung_ufs_phy(phy);
+
+	samsung_ufs_phy_ctrl_isol(ss_phy, true);
+	return 0;
+}
+
+static int samsung_ufs_phy_set_mode(struct phy *generic_phy,
+				    enum phy_mode mode, int submode)
+{
+	struct samsung_ufs_phy *ss_phy = get_samsung_ufs_phy(generic_phy);
+
+	ss_phy->mode = PHY_MODE_INVALID;
+
+	if (mode > 0)
+		ss_phy->mode = mode;
+
+	return 0;
+}
+
+static int samsung_ufs_phy_exit(struct phy *phy)
+{
+	struct samsung_ufs_phy *ss_phy = get_samsung_ufs_phy(phy);
+
+	clk_disable_unprepare(ss_phy->ref_clk);
+
+	if (ss_phy->drvdata->has_symbol_clk) {
+		clk_disable_unprepare(ss_phy->tx0_symbol_clk);
+		clk_disable_unprepare(ss_phy->rx0_symbol_clk);
+		clk_disable_unprepare(ss_phy->rx1_symbol_clk);
+	}
+
+	return 0;
+}
+
+static struct phy_ops samsung_ufs_phy_ops = {
+	.init		= samsung_ufs_phy_init,
+	.exit		= samsung_ufs_phy_exit,
+	.power_on	= samsung_ufs_phy_power_on,
+	.power_off	= samsung_ufs_phy_power_off,
+	.calibrate	= samsung_ufs_phy_calibrate,
+	.set_mode	= samsung_ufs_phy_set_mode,
+	.owner          = THIS_MODULE,
+};
+
+static const struct of_device_id samsung_ufs_phy_match[];
+
+static int samsung_ufs_phy_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct of_device_id *match;
+	struct samsung_ufs_phy *phy;
+	struct phy *gen_phy;
+	struct phy_provider *phy_provider;
+	const struct samsung_ufs_phy_drvdata *drvdata;
+	int err = 0;
+
+	match = of_match_node(samsung_ufs_phy_match, dev->of_node);
+	if (!match) {
+		err = -EINVAL;
+		dev_err(dev, "failed to get match_node\n");
+		goto out;
+	}
+
+	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
+	if (!phy) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	phy->reg_pma = devm_platform_ioremap_resource_byname(pdev, "phy-pma");
+	if (IS_ERR(phy->reg_pma)) {
+		err = PTR_ERR(phy->reg_pma);
+		goto out;
+	}
+
+	phy->reg_pmu = syscon_regmap_lookup_by_phandle(
+				dev->of_node, "samsung,pmu-syscon");
+	if (IS_ERR(phy->reg_pmu)) {
+		err = PTR_ERR(phy->reg_pmu);
+		dev_err(dev, "failed syscon remap for pmu\n");
+		goto out;
+	}
+
+	gen_phy = devm_phy_create(dev, NULL, &samsung_ufs_phy_ops);
+	if (IS_ERR(gen_phy)) {
+		err = PTR_ERR(gen_phy);
+		dev_err(dev, "failed to create PHY for ufs-phy\n");
+		goto out;
+	}
+
+	drvdata = match->data;
+	phy->dev = dev;
+	phy->drvdata = drvdata;
+	phy->cfg = (struct samsung_ufs_phy_cfg **)drvdata->cfg;
+	phy->isol = &drvdata->isol;
+	phy->lane_cnt = PHY_DEF_LANE_CNT;
+
+	phy_set_drvdata(gen_phy, phy);
+
+	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+	if (IS_ERR(phy_provider)) {
+		err = PTR_ERR(phy_provider);
+		dev_err(dev, "failed to register phy-provider\n");
+		goto out;
+	}
+out:
+	return err;
+}
+
+static const struct of_device_id samsung_ufs_phy_match[] = {
+	{
+		.compatible = "samsung,exynos7-ufs-phy",
+		.data = &exynos7_ufs_phy,
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, samsung_ufs_phy_match);
+
+static struct platform_driver samsung_ufs_phy_driver = {
+	.probe  = samsung_ufs_phy_probe,
+	.driver = {
+		.name = "samsung-ufs-phy",
+		.of_match_table = samsung_ufs_phy_match,
+	},
+};
+module_platform_driver(samsung_ufs_phy_driver);
+MODULE_DESCRIPTION("Samsung SoC UFS PHY Driver");
+MODULE_AUTHOR("Seungwon Jeon <essuuj@gmail.com>");
+MODULE_AUTHOR("Alim Akhtar <alim.akhtar@samsung.com>");
+MODULE_LICENSE("GPL v2");