1 files changed, 164 insertions, 0 deletions
diff --git a/drivers/phy/tegra/phy-tegra194-p2u.c b/drivers/phy/tegra/phy-tegra194-p2u.c
new file mode 100644
index 000000000..1415ca71d
--- /dev/null
+++ b/drivers/phy/tegra/phy-tegra194-p2u.c
@@ -0,0 +1,164 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * P2U (PIPE to UPHY) driver for Tegra T194 SoC
+ *
+ * Copyright (C) 2019-2022 NVIDIA Corporation.
+ *
+ * Author: Vidya Sagar <vidyas@nvidia.com>
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/phy/phy.h>
+
+#define P2U_CONTROL_CMN			0x74
+#define P2U_CONTROL_CMN_SKP_SIZE_PROTECTION_EN			BIT(20)
+
+#define P2U_PERIODIC_EQ_CTRL_GEN3	0xc0
+#define P2U_PERIODIC_EQ_CTRL_GEN3_PERIODIC_EQ_EN		BIT(0)
+#define P2U_PERIODIC_EQ_CTRL_GEN3_INIT_PRESET_EQ_TRAIN_EN	BIT(1)
+#define P2U_PERIODIC_EQ_CTRL_GEN4	0xc4
+#define P2U_PERIODIC_EQ_CTRL_GEN4_INIT_PRESET_EQ_TRAIN_EN	BIT(1)
+
+#define P2U_RX_DEBOUNCE_TIME				0xa4
+#define P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_MASK	0xffff
+#define P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_VAL		160
+
+#define P2U_DIR_SEARCH_CTRL				0xd4
+#define P2U_DIR_SEARCH_CTRL_GEN4_FINE_GRAIN_SEARCH_TWICE	BIT(18)
+
+struct tegra_p2u_of_data {
+	bool one_dir_search;
+};
+
+struct tegra_p2u {
+	void __iomem *base;
+	bool skip_sz_protection_en; /* Needed to support two retimers */
+	struct tegra_p2u_of_data *of_data;
+};
+
+static inline void p2u_writel(struct tegra_p2u *phy, const u32 value,
+			      const u32 reg)
+{
+	writel_relaxed(value, phy->base + reg);
+}
+
+static inline u32 p2u_readl(struct tegra_p2u *phy, const u32 reg)
+{
+	return readl_relaxed(phy->base + reg);
+}
+
+static int tegra_p2u_power_on(struct phy *x)
+{
+	struct tegra_p2u *phy = phy_get_drvdata(x);
+	u32 val;
+
+	if (phy->skip_sz_protection_en) {
+		val = p2u_readl(phy, P2U_CONTROL_CMN);
+		val |= P2U_CONTROL_CMN_SKP_SIZE_PROTECTION_EN;
+		p2u_writel(phy, val, P2U_CONTROL_CMN);
+	}
+
+	val = p2u_readl(phy, P2U_PERIODIC_EQ_CTRL_GEN3);
+	val &= ~P2U_PERIODIC_EQ_CTRL_GEN3_PERIODIC_EQ_EN;
+	val |= P2U_PERIODIC_EQ_CTRL_GEN3_INIT_PRESET_EQ_TRAIN_EN;
+	p2u_writel(phy, val, P2U_PERIODIC_EQ_CTRL_GEN3);
+
+	val = p2u_readl(phy, P2U_PERIODIC_EQ_CTRL_GEN4);
+	val |= P2U_PERIODIC_EQ_CTRL_GEN4_INIT_PRESET_EQ_TRAIN_EN;
+	p2u_writel(phy, val, P2U_PERIODIC_EQ_CTRL_GEN4);
+
+	val = p2u_readl(phy, P2U_RX_DEBOUNCE_TIME);
+	val &= ~P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_MASK;
+	val |= P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_VAL;
+	p2u_writel(phy, val, P2U_RX_DEBOUNCE_TIME);
+
+	if (phy->of_data->one_dir_search) {
+		val = p2u_readl(phy, P2U_DIR_SEARCH_CTRL);
+		val &= ~P2U_DIR_SEARCH_CTRL_GEN4_FINE_GRAIN_SEARCH_TWICE;
+		p2u_writel(phy, val, P2U_DIR_SEARCH_CTRL);
+	}
+
+	return 0;
+}
+
+static const struct phy_ops ops = {
+	.power_on = tegra_p2u_power_on,
+	.owner = THIS_MODULE,
+};
+
+static int tegra_p2u_probe(struct platform_device *pdev)
+{
+	struct phy_provider *phy_provider;
+	struct device *dev = &pdev->dev;
+	struct phy *generic_phy;
+	struct tegra_p2u *phy;
+
+	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
+	if (!phy)
+		return -ENOMEM;
+
+	phy->of_data =
+		(struct tegra_p2u_of_data *)of_device_get_match_data(dev);
+	if (!phy->of_data)
+		return -EINVAL;
+
+	phy->base = devm_platform_ioremap_resource_byname(pdev, "ctl");
+	if (IS_ERR(phy->base))
+		return PTR_ERR(phy->base);
+
+	phy->skip_sz_protection_en =
+		of_property_read_bool(dev->of_node,
+				      "nvidia,skip-sz-protect-en");
+
+	platform_set_drvdata(pdev, phy);
+
+	generic_phy = devm_phy_create(dev, NULL, &ops);
+	if (IS_ERR(generic_phy))
+		return PTR_ERR(generic_phy);
+
+	phy_set_drvdata(generic_phy, phy);
+
+	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+	if (IS_ERR(phy_provider))
+		return PTR_ERR(phy_provider);
+
+	return 0;
+}
+
+static const struct tegra_p2u_of_data tegra194_p2u_of_data = {
+	.one_dir_search = false,
+};
+
+static const struct tegra_p2u_of_data tegra234_p2u_of_data = {
+	.one_dir_search = true,
+};
+
+static const struct of_device_id tegra_p2u_id_table[] = {
+	{
+		.compatible = "nvidia,tegra194-p2u",
+		.data = &tegra194_p2u_of_data,
+	},
+	{
+		.compatible = "nvidia,tegra234-p2u",
+		.data = &tegra234_p2u_of_data,
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, tegra_p2u_id_table);
+
+static struct platform_driver tegra_p2u_driver = {
+	.probe = tegra_p2u_probe,
+	.driver = {
+		.name = "tegra194-p2u",
+		.of_match_table = tegra_p2u_id_table,
+	},
+};
+module_platform_driver(tegra_p2u_driver);
+
+MODULE_AUTHOR("Vidya Sagar <vidyas@nvidia.com>");
+MODULE_DESCRIPTION("NVIDIA Tegra194 PIPE2UPHY PHY driver");
+MODULE_LICENSE("GPL v2");