phy: rockchip: Add Rockchip Synopsys PCIe 3.0 PHY

Add the Rockchip Synopsys based PCIe 3.0 PHY driver as
part of Generic PHY framework.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Kever Yang<kever.yang@rock-chips.com>

1 files changed, 157 insertions, 0 deletions

diff --git a/drivers/phy/rockchip/phy-rockchip-snps-pcie3.c b/drivers/phy/rockchip/phy-rockchip-snps-pcie3.c
new file mode 100644
index 0000000000..5ae41fbeee
--- /dev/null
+++ b/drivers/phy/rockchip/phy-rockchip-snps-pcie3.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Rockchip PCIE3.0 phy driver
+ *
+ * Copyright (C) 2021 Rockchip Electronics Co., Ltd.
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <generic-phy.h>
+#include <regmap.h>
+#include <reset-uclass.h>
+#include <syscon.h>
+#include <asm/io.h>
+#include <dm/device_compat.h>
+#include <dm/lists.h>
+
+#define GRF_PCIE30PHY_CON1 0x4
+#define GRF_PCIE30PHY_CON6 0x18
+#define GRF_PCIE30PHY_CON9 0x24
+
+/**
+ * struct rockchip_p3phy_priv - RK DW PCIe PHY state
+ *
+ * @mmio: The base address of PHY internal registers
+ * @phy_grf: The regmap for controlling pipe signal
+ * @p30phy: The reset signal for PHY
+ * @ref_clk_m: The reference clock of M for PHY
+ * @ref_clk_n: The reference clock of N for PHY
+ * @pclk: The clock for accessing PHY blocks
+ */
+struct rockchip_p3phy_priv {
+	void __iomem *mmio;
+	struct regmap *phy_grf;
+	struct reset_ctl p30phy;
+	struct clk ref_clk_m;
+	struct clk ref_clk_n;
+	struct clk pclk;
+};
+
+static int rochchip_p3phy_init(struct phy *phy)
+{
+	struct rockchip_p3phy_priv *priv = dev_get_priv(phy->dev);
+	int ret;
+
+	ret = clk_enable(&priv->ref_clk_m);
+	if (ret < 0 && ret != -ENOSYS)
+		return ret;
+
+	ret = clk_enable(&priv->ref_clk_n);
+	if (ret < 0 && ret != -ENOSYS)
+		goto err_ref;
+
+	ret = clk_enable(&priv->pclk);
+	if (ret < 0 && ret != -ENOSYS)
+		goto err_pclk;
+
+	reset_assert(&priv->p30phy);
+	udelay(1);
+
+	/* Deassert PCIe PMA output clamp mode */
+	regmap_write(priv->phy_grf, GRF_PCIE30PHY_CON9,
+		     (0x1 << 15) | (0x1 << 31));
+
+	reset_deassert(&priv->p30phy);
+	udelay(1);
+
+	return 0;
+err_pclk:
+	clk_disable(&priv->ref_clk_n);
+err_ref:
+	clk_disable(&priv->ref_clk_m);
+
+	return ret;
+}
+
+static int rochchip_p3phy_exit(struct phy *phy)
+{
+	struct rockchip_p3phy_priv *priv = dev_get_priv(phy->dev);
+
+	clk_disable(&priv->ref_clk_m);
+	clk_disable(&priv->ref_clk_n);
+	clk_disable(&priv->pclk);
+	reset_assert(&priv->p30phy);
+
+	return 0;
+}
+
+static int rockchip_p3phy_probe(struct udevice *dev)
+{
+	struct rockchip_p3phy_priv *priv = dev_get_priv(dev);
+	struct udevice *syscon;
+	int ret;
+
+	priv->mmio = (void __iomem *)dev_read_addr(dev);
+	if ((fdt_addr_t)priv->mmio == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	ret = uclass_get_device_by_phandle(UCLASS_SYSCON, dev,
+					   "rockchip,phy-grf",  &syscon);
+	if (ret) {
+		pr_err("unable to find syscon device for rockchip,phy-grf\n");
+		return ret;
+	}
+
+	priv->phy_grf = syscon_get_regmap(syscon);
+	if (IS_ERR(priv->phy_grf)) {
+		dev_err(dev, "failed to find rockchip,phy_grf regmap\n");
+		return PTR_ERR(priv->phy_grf);
+	}
+
+	ret = reset_get_by_name(dev, "phy", &priv->p30phy);
+	if (ret) {
+		dev_err(dev, "no phy reset control specified\n");
+		return ret;
+	}
+
+	ret = clk_get_by_name(dev, "refclk_m", &priv->ref_clk_m);
+	if (ret) {
+		dev_err(dev, "failed to find ref clock M\n");
+		return PTR_ERR(&priv->ref_clk_m);
+	}
+
+	ret = clk_get_by_name(dev, "refclk_n", &priv->ref_clk_n);
+	if (ret) {
+		dev_err(dev, "failed to find ref clock N\n");
+		return PTR_ERR(&priv->ref_clk_n);
+	}
+
+	ret = clk_get_by_name(dev, "pclk", &priv->pclk);
+	if (ret) {
+		dev_err(dev, "failed to find pclk\n");
+		return PTR_ERR(&priv->pclk);
+	}
+
+	return 0;
+}
+
+static struct phy_ops rochchip_p3phy_ops = {
+	.init = rochchip_p3phy_init,
+	.exit = rochchip_p3phy_exit,
+};
+
+static const struct udevice_id rockchip_p3phy_of_match[] = {
+	{ .compatible = "rockchip,rk3568-pcie3-phy" },
+	{ },
+};
+
+U_BOOT_DRIVER(rockchip_pcie3phy) = {
+	.name		= "rockchip_pcie3phy",
+	.id		= UCLASS_PHY,
+	.of_match	= rockchip_p3phy_of_match,
+	.ops		= &rochchip_p3phy_ops,
+	.probe		= rockchip_p3phy_probe,
+	.priv_auto	= sizeof(struct rockchip_p3phy_priv),
+};