// SPDX-License-Identifier: GPL-2.0-only
/*
* Rockchip PCIe PHY driver
*
* Copyright (C) 2016 Shawn Lin <[email protected]>
* Copyright (C) 2016 ROCKCHIP, Inc.
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/reset.h>
/*
* 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_A_STATUS 0x30
#define PHY_LANE_B_STATUS 0x31
#define PHY_LANE_C_STATUS 0x32
#define PHY_LANE_D_STATUS 0x33
#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_data {
unsigned int pcie_conf;
unsigned int pcie_status;
unsigned int pcie_laneoff;
};
struct rockchip_pcie_phy {
const struct rockchip_pcie_data *phy_data;
struct regmap *reg_base;
struct phy_pcie_instance {
struct phy *phy;
u32 index;
} phys[PHY_MAX_LANE_NUM];
struct mutex pcie_mutex;
struct reset_control *phy_rst;
struct clk *clk_pciephy_ref;
int pwr_cnt;
int init_cnt;
};
static struct rockchip_pcie_phy *to_pcie_phy(struct phy_pcie_instance *inst)
{
return container_of(inst, struct rockchip_pcie_phy,
phys[inst->index]);
}
static struct phy *rockchip_pcie_phy_of_xlate(struct device *dev,
const struct of_phandle_args *args)
{
struct rockchip_pcie_phy *rk_phy = dev_get_drvdata(dev);
if (args->args_count == 0)
return rk_phy->phys[0].phy;
if (WARN_ON(args->args[0] >= PHY_MAX_LANE_NUM))
return ERR_PTR(-ENODEV);
return rk_phy->phys[args->args[0]].phy;
}
static inline void phy_wr_cfg(struct rockchip_pcie_phy *rk_phy,
u32 addr, u32 data)
{
regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,
HIWORD_UPDATE(data,
PHY_CFG_DATA_MASK,
PHY_CFG_DATA_SHIFT) |
HIWORD_UPDATE(addr,
PHY_CFG_ADDR_MASK,
PHY_CFG_ADDR_SHIFT));
udelay(1);
regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,
HIWORD_UPDATE(PHY_CFG_WR_ENABLE,
PHY_CFG_WR_MASK,
PHY_CFG_WR_SHIFT));
udelay(1);
regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,
HIWORD_UPDATE(PHY_CFG_WR_DISABLE,
PHY_CFG_WR_MASK,
PHY_CFG_WR_SHIFT));
}
static int rockchip_pcie_phy_power_off(struct phy *phy)
{
struct phy_pcie_instance *inst = phy_get_drvdata(phy);
struct rockchip_pcie_phy *rk_phy = to_pcie_phy(inst);
int err = 0;
mutex_lock(&rk_phy->pcie_mutex);
regmap_write(rk_phy->reg_base,
rk_phy->phy_data->pcie_laneoff,
HIWORD_UPDATE(PHY_LANE_IDLE_OFF,
PHY_LANE_IDLE_MASK,
PHY_LANE_IDLE_A_SHIFT + inst->index));
if (--rk_phy->pwr_cnt)
goto err_out;
err = reset_control_assert(rk_phy->phy_rst);
if (err) {
dev_err(&phy->dev, "assert phy_rst err %d\n", err);
goto err_restore;
}
err_out:
mutex_unlock(&rk_phy->pcie_mutex);
return 0;
err_restore:
rk_phy->pwr_cnt++;
regmap_write(rk_phy->reg_base,
rk_phy->phy_data->pcie_laneoff,
HIWORD_UPDATE(!PHY_LANE_IDLE_OFF,
PHY_LANE_IDLE_MASK,
PHY_LANE_IDLE_A_SHIFT + inst->index));
mutex_unlock(&rk_phy->pcie_mutex);
return err;
}
static int rockchip_pcie_phy_power_on(struct phy *phy)
{
struct phy_pcie_instance *inst = phy_get_drvdata(phy);
struct rockchip_pcie_phy *rk_phy = to_pcie_phy(inst);
int err = 0;
u32 status;
unsigned long timeout;
mutex_lock(&rk_phy->pcie_mutex);
if (rk_phy->pwr_cnt++)
goto err_out;
err = reset_control_deassert(rk_phy->phy_rst);
if (err) {
dev_err(&phy->dev, "deassert phy_rst err %d\n", err);
goto err_pwr_cnt;
}
regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,
HIWORD_UPDATE(PHY_CFG_PLL_LOCK,
PHY_CFG_ADDR_MASK,
PHY_CFG_ADDR_SHIFT));
regmap_write(rk_phy->reg_base,
rk_phy->phy_data->pcie_laneoff,
HIWORD_UPDATE(!PHY_LANE_IDLE_OFF,
PHY_LANE_IDLE_MASK,
PHY_LANE_IDLE_A_SHIFT + inst->index));
/*
* No documented timeout value for phy operation below,
* so we make it large enough here. And we use loop-break
* method which should not be harmful.
*/
timeout = jiffies + msecs_to_jiffies(1000);
err = -EINVAL;
while (time_before(jiffies, timeout)) {
regmap_read(rk_phy->reg_base,
rk_phy->phy_data->pcie_status,
&status);
if (status & PHY_PLL_LOCKED) {
dev_dbg(&phy->dev, "pll locked!\n");
err = 0;
break;
}
msleep(20);
}
if (err) {
dev_err(&phy->dev, "pll lock timeout!\n");
goto err_pll_lock;
}
phy_wr_cfg(rk_phy, PHY_CFG_CLK_TEST, PHY_CFG_SEPE_RATE);
phy_wr_cfg(rk_phy, PHY_CFG_CLK_SCC, PHY_CFG_PLL_100M);
err = -ETIMEDOUT;
while (time_before(jiffies, timeout)) {
regmap_read(rk_phy->reg_base,
rk_phy->phy_data->pcie_status,
&status);
if (!(status & PHY_PLL_OUTPUT)) {
dev_dbg(&phy->dev, "pll output enable done!\n");
err = 0;
break;
}
msleep(20);
}
if (err) {
dev_err(&phy->dev, "pll output enable timeout!\n");
goto err_pll_lock;
}
regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,
HIWORD_UPDATE(PHY_CFG_PLL_LOCK,
PHY_CFG_ADDR_MASK,
PHY_CFG_ADDR_SHIFT));
err = -EINVAL;
while (time_before(jiffies, timeout)) {
regmap_read(rk_phy->reg_base,
rk_phy->phy_data->pcie_status,
&status);
if (status & PHY_PLL_LOCKED) {
dev_dbg(&phy->dev, "pll relocked!\n");
err = 0;
break;
}
msleep(20);
}
if (err) {
dev_err(&phy->dev, "pll relock timeout!\n");
goto err_pll_lock;
}
err_out:
mutex_unlock(&rk_phy->pcie_mutex);
return 0;
err_pll_lock:
reset_control_assert(rk_phy->phy_rst);
err_pwr_cnt:
rk_phy->pwr_cnt--;
mutex_unlock(&rk_phy->pcie_mutex);
return err;
}
static int rockchip_pcie_phy_init(struct phy *phy)
{
struct phy_pcie_instance *inst = phy_get_drvdata(phy);
struct rockchip_pcie_phy *rk_phy = to_pcie_phy(inst);
int err = 0;
mutex_lock(&rk_phy->pcie_mutex);
if (rk_phy->init_cnt++)
goto err_out;
err = clk_prepare_enable(rk_phy->clk_pciephy_ref);
if (err) {
dev_err(&phy->dev, "Fail to enable pcie ref clock.\n");
goto err_refclk;
}
err = reset_control_assert(rk_phy->phy_rst);
if (err) {
dev_err(&phy->dev, "assert phy_rst err %d\n", err);
goto err_reset;
}
err_out:
mutex_unlock(&rk_phy->pcie_mutex);
return 0;
err_reset:
clk_disable_unprepare(rk_phy->clk_pciephy_ref);
err_refclk:
rk_phy->init_cnt--;
mutex_unlock(&rk_phy->pcie_mutex);
return err;
}
static int rockchip_pcie_phy_exit(struct phy *phy)
{
struct phy_pcie_instance *inst = phy_get_drvdata(phy);
struct rockchip_pcie_phy *rk_phy = to_pcie_phy(inst);
mutex_lock(&rk_phy->pcie_mutex);
if (--rk_phy->init_cnt)
goto err_init_cnt;
clk_disable_unprepare(rk_phy->clk_pciephy_ref);
err_init_cnt:
mutex_unlock(&rk_phy->pcie_mutex);
return 0;
}
static const struct phy_ops ops = {
.init = rockchip_pcie_phy_init,
.exit = rockchip_pcie_phy_exit,
.power_on = rockchip_pcie_phy_power_on,
.power_off = rockchip_pcie_phy_power_off,
.owner = THIS_MODULE,
};
static const struct rockchip_pcie_data rk3399_pcie_data = {
.pcie_conf = 0xe220,
.pcie_status = 0xe2a4,
.pcie_laneoff = 0xe214,
};
static const struct of_device_id rockchip_pcie_phy_dt_ids[] = {
{
.compatible = "rockchip,rk3399-pcie-phy",
.data = &rk3399_pcie_data,
},
{}
};
MODULE_DEVICE_TABLE(of, rockchip_pcie_phy_dt_ids);
static int rockchip_pcie_phy_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct rockchip_pcie_phy *rk_phy;
struct phy_provider *phy_provider;
struct regmap *grf;
int i;
u32 phy_num;
grf = syscon_node_to_regmap(dev->parent->of_node);
if (IS_ERR(grf)) {
dev_err(dev, "Cannot find GRF syscon\n");
return PTR_ERR(grf);
}
rk_phy = devm_kzalloc(dev, sizeof(*rk_phy), GFP_KERNEL);
if (!rk_phy)
return -ENOMEM;
rk_phy->phy_data = device_get_match_data(&pdev->dev);
if (!rk_phy->phy_data)
return -EINVAL;
rk_phy->reg_base = grf;
mutex_init(&rk_phy->pcie_mutex);
rk_phy->phy_rst = devm_reset_control_get(dev, "phy");
if (IS_ERR(rk_phy->phy_rst)) {
if (PTR_ERR(rk_phy->phy_rst) != -EPROBE_DEFER)
dev_err(dev,
"missing phy property for reset controller\n");
return PTR_ERR(rk_phy->phy_rst);
}
rk_phy->clk_pciephy_ref = devm_clk_get(dev, "refclk");
if (IS_ERR(rk_phy->clk_pciephy_ref)) {
dev_err(dev, "refclk not found.\n");
return PTR_ERR(rk_phy->clk_pciephy_ref);
}
/* parse #phy-cells to see if it's legacy PHY model */
if (of_property_read_u32(dev->of_node, "#phy-cells", &phy_num))
return -ENOENT;
phy_num = (phy_num == 0) ? 1 : PHY_MAX_LANE_NUM;
dev_dbg(dev, "phy number is %d\n", phy_num);
for (i = 0; i < phy_num; i++) {
rk_phy->phys[i].phy = devm_phy_create(dev, dev->of_node, &ops);
if (IS_ERR(rk_phy->phys[i].phy)) {
dev_err(dev, "failed to create PHY%d\n", i);
return PTR_ERR(rk_phy->phys[i].phy);
}
rk_phy->phys[i].index = i;
phy_set_drvdata(rk_phy->phys[i].phy, &rk_phy->phys[i]);
}
platform_set_drvdata(pdev, rk_phy);
phy_provider = devm_of_phy_provider_register(dev,
rockchip_pcie_phy_of_xlate);
return PTR_ERR_OR_ZERO(phy_provider);
}
static struct platform_driver rockchip_pcie_driver = {
.probe = rockchip_pcie_phy_probe,
.driver = {
.name = "rockchip-pcie-phy",
.of_match_table = rockchip_pcie_phy_dt_ids,
},
};
module_platform_driver(rockchip_pcie_driver);
MODULE_AUTHOR("Shawn Lin <[email protected]>");
MODULE_DESCRIPTION("Rockchip PCIe PHY driver");
MODULE_LICENSE("GPL v2");
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