// SPDX-License-Identifier: (GPL-2.0-only)
/*
 * Rockchip PCIe PHY driver
 *
 * Copyright (C) 2020 Amarula Solutions(India)
 * Copyright (C) 2016 Shawn Lin <shawn.lin@rock-chips.com>
 * Copyright (C) 2016 ROCKCHIP, Inc.
 */

#include <common.h>
#include <clk.h>
#include <dm.h>
#include <dm/device_compat.h>
#include <generic-phy.h>
#include <reset.h>
#include <syscon.h>
#include <asm/gpio.h>
#include <asm/io.h>
#include <linux/iopoll.h>
#include <asm/arch-rockchip/clock.h>

DECLARE_GLOBAL_DATA_PTR;

/*
 * The higher 16-bit of this register is used for write protection
 * only if BIT(x + 16) set to 1 the BIT(x) can be written.
 */
#define HIWORD_UPDATE(val, mask, shift) \
		((val) << (shift) | (mask) << ((shift) + 16))

#define PHY_MAX_LANE_NUM      4
#define PHY_CFG_DATA_SHIFT    7
#define PHY_CFG_ADDR_SHIFT    1
#define PHY_CFG_DATA_MASK     0xf
#define PHY_CFG_ADDR_MASK     0x3f
#define PHY_CFG_RD_MASK       0x3ff
#define PHY_CFG_WR_ENABLE     1
#define PHY_CFG_WR_DISABLE    1
#define PHY_CFG_WR_SHIFT      0
#define PHY_CFG_WR_MASK       1
#define PHY_CFG_PLL_LOCK      0x10
#define PHY_CFG_CLK_TEST      0x10
#define PHY_CFG_CLK_SCC       0x12
#define PHY_CFG_SEPE_RATE     BIT(3)
#define PHY_CFG_PLL_100M      BIT(3)
#define PHY_PLL_LOCKED        BIT(9)
#define PHY_PLL_OUTPUT        BIT(10)
#define PHY_LANE_RX_DET_SHIFT 11
#define PHY_LANE_RX_DET_TH    0x1
#define PHY_LANE_IDLE_OFF     0x1
#define PHY_LANE_IDLE_MASK    0x1
#define PHY_LANE_IDLE_A_SHIFT 3
#define PHY_LANE_IDLE_B_SHIFT 4
#define PHY_LANE_IDLE_C_SHIFT 5
#define PHY_LANE_IDLE_D_SHIFT 6

struct rockchip_pcie_phy_data {
	unsigned int pcie_conf;
	unsigned int pcie_status;
	unsigned int pcie_laneoff;
};

struct rockchip_pcie_phy {
	void *reg_base;
	struct clk refclk;
	struct reset_ctl phy_rst;
	const struct rockchip_pcie_phy_data *data;
};

static void phy_wr_cfg(struct rockchip_pcie_phy *priv, u32 addr, u32 data)
{
	u32 reg;

	reg = HIWORD_UPDATE(data, PHY_CFG_DATA_MASK, PHY_CFG_DATA_SHIFT);
	reg |= HIWORD_UPDATE(addr, PHY_CFG_ADDR_MASK, PHY_CFG_ADDR_SHIFT);
	writel(reg, priv->reg_base + priv->data->pcie_conf);

	udelay(1);

	reg = HIWORD_UPDATE(PHY_CFG_WR_ENABLE,
			    PHY_CFG_WR_MASK,
			    PHY_CFG_WR_SHIFT);
	writel(reg, priv->reg_base + priv->data->pcie_conf);

	udelay(1);

	reg = HIWORD_UPDATE(PHY_CFG_WR_DISABLE,
			    PHY_CFG_WR_MASK,
			    PHY_CFG_WR_SHIFT);
	writel(reg, priv->reg_base + priv->data->pcie_conf);
}

static int rockchip_pcie_phy_power_on(struct phy *phy)
{
	struct rockchip_pcie_phy *priv = dev_get_priv(phy->dev);
	int ret = 0;
	u32 reg, status;

	ret = reset_deassert(&priv->phy_rst);
	if (ret) {
		dev_err(phy->dev, "failed to assert phy reset\n");
		return ret;
	}

	reg = HIWORD_UPDATE(PHY_CFG_PLL_LOCK,
			    PHY_CFG_ADDR_MASK,
			    PHY_CFG_ADDR_SHIFT);
	writel(reg, priv->reg_base + priv->data->pcie_conf);

	reg = HIWORD_UPDATE(!PHY_LANE_IDLE_OFF,
			    PHY_LANE_IDLE_MASK,
			    PHY_LANE_IDLE_A_SHIFT);
	writel(reg, priv->reg_base + priv->data->pcie_laneoff);

	ret = -EINVAL;
	ret = readl_poll_sleep_timeout(priv->reg_base + priv->data->pcie_status,
				       status,
				       status & PHY_PLL_LOCKED,
				       20 * 1000,
				       50);
	if (ret) {
		dev_err(phy->dev, "pll lock timeout!\n");
		goto err_pll_lock;
	}

	phy_wr_cfg(priv, PHY_CFG_CLK_TEST, PHY_CFG_SEPE_RATE);
	phy_wr_cfg(priv, PHY_CFG_CLK_SCC, PHY_CFG_PLL_100M);

	ret = -ETIMEDOUT;
	ret = readl_poll_sleep_timeout(priv->reg_base + priv->data->pcie_status,
				       status,
				       !(status & PHY_PLL_OUTPUT),
				       20 * 1000,
				       50);
	if (ret) {
		dev_err(phy->dev, "pll output enable timeout!\n");
		goto err_pll_lock;
	}

	reg = HIWORD_UPDATE(PHY_CFG_PLL_LOCK,
			    PHY_CFG_ADDR_MASK,
			    PHY_CFG_ADDR_SHIFT);
	writel(reg, priv->reg_base + priv->data->pcie_conf);

	ret = -EINVAL;
	ret = readl_poll_sleep_timeout(priv->reg_base + priv->data->pcie_status,
				       status,
				       status & PHY_PLL_LOCKED,
				       20 * 1000,
				       50);
	if (ret) {
		dev_err(phy->dev, "pll relock timeout!\n");
		goto err_pll_lock;
	}

	return 0;

err_pll_lock:
	reset_assert(&priv->phy_rst);
	return ret;
}

static int rockchip_pcie_phy_power_off(struct phy *phy)
{
	struct rockchip_pcie_phy *priv = dev_get_priv(phy->dev);
	int ret;
	u32 reg;

	reg = HIWORD_UPDATE(PHY_LANE_IDLE_OFF,
			    PHY_LANE_IDLE_MASK,
			    PHY_LANE_IDLE_A_SHIFT);
	writel(reg, priv->reg_base + priv->data->pcie_laneoff);

	ret = reset_assert(&priv->phy_rst);
	if (ret) {
		dev_err(phy->dev, "failed to assert phy reset\n");
		return ret;
	}

	return 0;
}

static int rockchip_pcie_phy_init(struct phy *phy)
{
	struct rockchip_pcie_phy *priv = dev_get_priv(phy->dev);
	int ret;

	ret = clk_enable(&priv->refclk);
	if (ret) {
		dev_err(phy->dev, "failed to enable refclk clock\n");
		return ret;
	}

	ret = reset_assert(&priv->phy_rst);
	if (ret) {
		dev_err(phy->dev, "failed to assert phy reset\n");
		goto err_reset;
	}

	return 0;

err_reset:
	clk_disable(&priv->refclk);
	return ret;
}

static int rockchip_pcie_phy_exit(struct phy *phy)
{
	struct rockchip_pcie_phy *priv = dev_get_priv(phy->dev);

	clk_disable(&priv->refclk);

	return 0;
}

static struct phy_ops rockchip_pcie_phy_ops = {
	.init = rockchip_pcie_phy_init,
	.power_on = rockchip_pcie_phy_power_on,
	.power_off = rockchip_pcie_phy_power_off,
	.exit = rockchip_pcie_phy_exit,
};

static int rockchip_pcie_phy_probe(struct udevice *dev)
{
	struct rockchip_pcie_phy *priv = dev_get_priv(dev);
	int ret;

	priv->data = (const struct rockchip_pcie_phy_data *)
						dev_get_driver_data(dev);
	if (!priv->data)
		return -EINVAL;

	priv->reg_base = syscon_get_first_range(ROCKCHIP_SYSCON_GRF);

	ret = clk_get_by_name(dev, "refclk", &priv->refclk);
	if (ret) {
		dev_err(dev, "failed to get refclk clock phandle\n");
		return ret;
	}

	ret = reset_get_by_name(dev, "phy", &priv->phy_rst);
	if (ret) {
		dev_err(dev, "failed to get phy reset phandle\n");
		return ret;
	}

	return 0;
}

static const struct rockchip_pcie_phy_data rk3399_pcie_data = {
	.pcie_conf = 0xe220,
	.pcie_status = 0xe2a4,
	.pcie_laneoff = 0xe214,
};

static const struct udevice_id rockchip_pcie_phy_ids[] = {
	{
		.compatible = "rockchip,rk3399-pcie-phy",
		.data = (ulong)&rk3399_pcie_data,
	},
	{ /* sentile */ }
};

U_BOOT_DRIVER(rockchip_pcie_phy) = {
	.name	= "rockchip_pcie_phy",
	.id	= UCLASS_PHY,
	.of_match = rockchip_pcie_phy_ids,
	.ops = &rockchip_pcie_phy_ops,
	.probe = rockchip_pcie_phy_probe,
	.priv_auto_alloc_size = sizeof(struct rockchip_pcie_phy),
};