brintos

brintos / linux-shallow public Read only

0
0
Text · 10.2 KiB · 51cc5ec Raw
424 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Rockchip PCIe PHY driver4 *5 * Copyright (C) 2016 Shawn Lin <shawn.lin@rock-chips.com>6 * Copyright (C) 2016 ROCKCHIP, Inc.7 */8 9#include <linux/clk.h>10#include <linux/delay.h>11#include <linux/io.h>12#include <linux/mfd/syscon.h>13#include <linux/module.h>14#include <linux/of.h>15#include <linux/phy/phy.h>16#include <linux/platform_device.h>17#include <linux/property.h>18#include <linux/regmap.h>19#include <linux/reset.h>20 21/*22 * The higher 16-bit of this register is used for write protection23 * only if BIT(x + 16) set to 1 the BIT(x) can be written.24 */25#define HIWORD_UPDATE(val, mask, shift) \26		((val) << (shift) | (mask) << ((shift) + 16))27 28#define PHY_MAX_LANE_NUM      429#define PHY_CFG_DATA_SHIFT    730#define PHY_CFG_ADDR_SHIFT    131#define PHY_CFG_DATA_MASK     0xf32#define PHY_CFG_ADDR_MASK     0x3f33#define PHY_CFG_RD_MASK       0x3ff34#define PHY_CFG_WR_ENABLE     135#define PHY_CFG_WR_DISABLE    136#define PHY_CFG_WR_SHIFT      037#define PHY_CFG_WR_MASK       138#define PHY_CFG_PLL_LOCK      0x1039#define PHY_CFG_CLK_TEST      0x1040#define PHY_CFG_CLK_SCC       0x1241#define PHY_CFG_SEPE_RATE     BIT(3)42#define PHY_CFG_PLL_100M      BIT(3)43#define PHY_PLL_LOCKED        BIT(9)44#define PHY_PLL_OUTPUT        BIT(10)45#define PHY_LANE_A_STATUS     0x3046#define PHY_LANE_B_STATUS     0x3147#define PHY_LANE_C_STATUS     0x3248#define PHY_LANE_D_STATUS     0x3349#define PHY_LANE_RX_DET_SHIFT 1150#define PHY_LANE_RX_DET_TH    0x151#define PHY_LANE_IDLE_OFF     0x152#define PHY_LANE_IDLE_MASK    0x153#define PHY_LANE_IDLE_A_SHIFT 354#define PHY_LANE_IDLE_B_SHIFT 455#define PHY_LANE_IDLE_C_SHIFT 556#define PHY_LANE_IDLE_D_SHIFT 657 58struct rockchip_pcie_data {59	unsigned int pcie_conf;60	unsigned int pcie_status;61	unsigned int pcie_laneoff;62};63 64struct rockchip_pcie_phy {65	const struct rockchip_pcie_data *phy_data;66	struct regmap *reg_base;67	struct phy_pcie_instance {68		struct phy *phy;69		u32 index;70	} phys[PHY_MAX_LANE_NUM];71	struct mutex pcie_mutex;72	struct reset_control *phy_rst;73	struct clk *clk_pciephy_ref;74	int pwr_cnt;75	int init_cnt;76};77 78static struct rockchip_pcie_phy *to_pcie_phy(struct phy_pcie_instance *inst)79{80	return container_of(inst, struct rockchip_pcie_phy,81					phys[inst->index]);82}83 84static struct phy *rockchip_pcie_phy_of_xlate(struct device *dev,85					      const struct of_phandle_args *args)86{87	struct rockchip_pcie_phy *rk_phy = dev_get_drvdata(dev);88 89	if (args->args_count == 0)90		return rk_phy->phys[0].phy;91 92	if (WARN_ON(args->args[0] >= PHY_MAX_LANE_NUM))93		return ERR_PTR(-ENODEV);94 95	return rk_phy->phys[args->args[0]].phy;96}97 98 99static inline void phy_wr_cfg(struct rockchip_pcie_phy *rk_phy,100			      u32 addr, u32 data)101{102	regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,103		     HIWORD_UPDATE(data,104				   PHY_CFG_DATA_MASK,105				   PHY_CFG_DATA_SHIFT) |106		     HIWORD_UPDATE(addr,107				   PHY_CFG_ADDR_MASK,108				   PHY_CFG_ADDR_SHIFT));109	udelay(1);110	regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,111		     HIWORD_UPDATE(PHY_CFG_WR_ENABLE,112				   PHY_CFG_WR_MASK,113				   PHY_CFG_WR_SHIFT));114	udelay(1);115	regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,116		     HIWORD_UPDATE(PHY_CFG_WR_DISABLE,117				   PHY_CFG_WR_MASK,118				   PHY_CFG_WR_SHIFT));119}120 121static int rockchip_pcie_phy_power_off(struct phy *phy)122{123	struct phy_pcie_instance *inst = phy_get_drvdata(phy);124	struct rockchip_pcie_phy *rk_phy = to_pcie_phy(inst);125	int err = 0;126 127	mutex_lock(&rk_phy->pcie_mutex);128 129	regmap_write(rk_phy->reg_base,130		     rk_phy->phy_data->pcie_laneoff,131		     HIWORD_UPDATE(PHY_LANE_IDLE_OFF,132				   PHY_LANE_IDLE_MASK,133				   PHY_LANE_IDLE_A_SHIFT + inst->index));134 135	if (--rk_phy->pwr_cnt)136		goto err_out;137 138	err = reset_control_assert(rk_phy->phy_rst);139	if (err) {140		dev_err(&phy->dev, "assert phy_rst err %d\n", err);141		goto err_restore;142	}143 144err_out:145	mutex_unlock(&rk_phy->pcie_mutex);146	return 0;147 148err_restore:149	rk_phy->pwr_cnt++;150	regmap_write(rk_phy->reg_base,151		     rk_phy->phy_data->pcie_laneoff,152		     HIWORD_UPDATE(!PHY_LANE_IDLE_OFF,153				   PHY_LANE_IDLE_MASK,154				   PHY_LANE_IDLE_A_SHIFT + inst->index));155	mutex_unlock(&rk_phy->pcie_mutex);156	return err;157}158 159static int rockchip_pcie_phy_power_on(struct phy *phy)160{161	struct phy_pcie_instance *inst = phy_get_drvdata(phy);162	struct rockchip_pcie_phy *rk_phy = to_pcie_phy(inst);163	int err = 0;164	u32 status;165	unsigned long timeout;166 167	mutex_lock(&rk_phy->pcie_mutex);168 169	if (rk_phy->pwr_cnt++)170		goto err_out;171 172	err = reset_control_deassert(rk_phy->phy_rst);173	if (err) {174		dev_err(&phy->dev, "deassert phy_rst err %d\n", err);175		goto err_pwr_cnt;176	}177 178	regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,179		     HIWORD_UPDATE(PHY_CFG_PLL_LOCK,180				   PHY_CFG_ADDR_MASK,181				   PHY_CFG_ADDR_SHIFT));182 183	regmap_write(rk_phy->reg_base,184		     rk_phy->phy_data->pcie_laneoff,185		     HIWORD_UPDATE(!PHY_LANE_IDLE_OFF,186				   PHY_LANE_IDLE_MASK,187				   PHY_LANE_IDLE_A_SHIFT + inst->index));188 189	/*190	 * No documented timeout value for phy operation below,191	 * so we make it large enough here. And we use loop-break192	 * method which should not be harmful.193	 */194	timeout = jiffies + msecs_to_jiffies(1000);195 196	err = -EINVAL;197	while (time_before(jiffies, timeout)) {198		regmap_read(rk_phy->reg_base,199			    rk_phy->phy_data->pcie_status,200			    &status);201		if (status & PHY_PLL_LOCKED) {202			dev_dbg(&phy->dev, "pll locked!\n");203			err = 0;204			break;205		}206		msleep(20);207	}208 209	if (err) {210		dev_err(&phy->dev, "pll lock timeout!\n");211		goto err_pll_lock;212	}213 214	phy_wr_cfg(rk_phy, PHY_CFG_CLK_TEST, PHY_CFG_SEPE_RATE);215	phy_wr_cfg(rk_phy, PHY_CFG_CLK_SCC, PHY_CFG_PLL_100M);216 217	err = -ETIMEDOUT;218	while (time_before(jiffies, timeout)) {219		regmap_read(rk_phy->reg_base,220			    rk_phy->phy_data->pcie_status,221			    &status);222		if (!(status & PHY_PLL_OUTPUT)) {223			dev_dbg(&phy->dev, "pll output enable done!\n");224			err = 0;225			break;226		}227		msleep(20);228	}229 230	if (err) {231		dev_err(&phy->dev, "pll output enable timeout!\n");232		goto err_pll_lock;233	}234 235	regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,236		     HIWORD_UPDATE(PHY_CFG_PLL_LOCK,237				   PHY_CFG_ADDR_MASK,238				   PHY_CFG_ADDR_SHIFT));239	err = -EINVAL;240	while (time_before(jiffies, timeout)) {241		regmap_read(rk_phy->reg_base,242			    rk_phy->phy_data->pcie_status,243			    &status);244		if (status & PHY_PLL_LOCKED) {245			dev_dbg(&phy->dev, "pll relocked!\n");246			err = 0;247			break;248		}249		msleep(20);250	}251 252	if (err) {253		dev_err(&phy->dev, "pll relock timeout!\n");254		goto err_pll_lock;255	}256 257err_out:258	mutex_unlock(&rk_phy->pcie_mutex);259	return 0;260 261err_pll_lock:262	reset_control_assert(rk_phy->phy_rst);263err_pwr_cnt:264	rk_phy->pwr_cnt--;265	mutex_unlock(&rk_phy->pcie_mutex);266	return err;267}268 269static int rockchip_pcie_phy_init(struct phy *phy)270{271	struct phy_pcie_instance *inst = phy_get_drvdata(phy);272	struct rockchip_pcie_phy *rk_phy = to_pcie_phy(inst);273	int err = 0;274 275	mutex_lock(&rk_phy->pcie_mutex);276 277	if (rk_phy->init_cnt++)278		goto err_out;279 280	err = clk_prepare_enable(rk_phy->clk_pciephy_ref);281	if (err) {282		dev_err(&phy->dev, "Fail to enable pcie ref clock.\n");283		goto err_refclk;284	}285 286	err = reset_control_assert(rk_phy->phy_rst);287	if (err) {288		dev_err(&phy->dev, "assert phy_rst err %d\n", err);289		goto err_reset;290	}291 292err_out:293	mutex_unlock(&rk_phy->pcie_mutex);294	return 0;295 296err_reset:297 298	clk_disable_unprepare(rk_phy->clk_pciephy_ref);299err_refclk:300	rk_phy->init_cnt--;301	mutex_unlock(&rk_phy->pcie_mutex);302	return err;303}304 305static int rockchip_pcie_phy_exit(struct phy *phy)306{307	struct phy_pcie_instance *inst = phy_get_drvdata(phy);308	struct rockchip_pcie_phy *rk_phy = to_pcie_phy(inst);309 310	mutex_lock(&rk_phy->pcie_mutex);311 312	if (--rk_phy->init_cnt)313		goto err_init_cnt;314 315	clk_disable_unprepare(rk_phy->clk_pciephy_ref);316 317err_init_cnt:318	mutex_unlock(&rk_phy->pcie_mutex);319	return 0;320}321 322static const struct phy_ops ops = {323	.init		= rockchip_pcie_phy_init,324	.exit		= rockchip_pcie_phy_exit,325	.power_on	= rockchip_pcie_phy_power_on,326	.power_off	= rockchip_pcie_phy_power_off,327	.owner		= THIS_MODULE,328};329 330static const struct rockchip_pcie_data rk3399_pcie_data = {331	.pcie_conf = 0xe220,332	.pcie_status = 0xe2a4,333	.pcie_laneoff = 0xe214,334};335 336static const struct of_device_id rockchip_pcie_phy_dt_ids[] = {337	{338		.compatible = "rockchip,rk3399-pcie-phy",339		.data = &rk3399_pcie_data,340	},341	{}342};343 344MODULE_DEVICE_TABLE(of, rockchip_pcie_phy_dt_ids);345 346static int rockchip_pcie_phy_probe(struct platform_device *pdev)347{348	struct device *dev = &pdev->dev;349	struct rockchip_pcie_phy *rk_phy;350	struct phy_provider *phy_provider;351	struct regmap *grf;352	int i;353	u32 phy_num;354 355	grf = syscon_node_to_regmap(dev->parent->of_node);356	if (IS_ERR(grf)) {357		dev_err(dev, "Cannot find GRF syscon\n");358		return PTR_ERR(grf);359	}360 361	rk_phy = devm_kzalloc(dev, sizeof(*rk_phy), GFP_KERNEL);362	if (!rk_phy)363		return -ENOMEM;364 365	rk_phy->phy_data = device_get_match_data(&pdev->dev);366	if (!rk_phy->phy_data)367		return -EINVAL;368 369	rk_phy->reg_base = grf;370 371	mutex_init(&rk_phy->pcie_mutex);372 373	rk_phy->phy_rst = devm_reset_control_get(dev, "phy");374	if (IS_ERR(rk_phy->phy_rst)) {375		if (PTR_ERR(rk_phy->phy_rst) != -EPROBE_DEFER)376			dev_err(dev,377				"missing phy property for reset controller\n");378		return PTR_ERR(rk_phy->phy_rst);379	}380 381	rk_phy->clk_pciephy_ref = devm_clk_get(dev, "refclk");382	if (IS_ERR(rk_phy->clk_pciephy_ref)) {383		dev_err(dev, "refclk not found.\n");384		return PTR_ERR(rk_phy->clk_pciephy_ref);385	}386 387	/* parse #phy-cells to see if it's legacy PHY model */388	if (of_property_read_u32(dev->of_node, "#phy-cells", &phy_num))389		return -ENOENT;390 391	phy_num = (phy_num == 0) ? 1 : PHY_MAX_LANE_NUM;392	dev_dbg(dev, "phy number is %d\n", phy_num);393 394	for (i = 0; i < phy_num; i++) {395		rk_phy->phys[i].phy = devm_phy_create(dev, dev->of_node, &ops);396		if (IS_ERR(rk_phy->phys[i].phy)) {397			dev_err(dev, "failed to create PHY%d\n", i);398			return PTR_ERR(rk_phy->phys[i].phy);399		}400		rk_phy->phys[i].index = i;401		phy_set_drvdata(rk_phy->phys[i].phy, &rk_phy->phys[i]);402	}403 404	platform_set_drvdata(pdev, rk_phy);405	phy_provider = devm_of_phy_provider_register(dev,406					rockchip_pcie_phy_of_xlate);407 408	return PTR_ERR_OR_ZERO(phy_provider);409}410 411static struct platform_driver rockchip_pcie_driver = {412	.probe		= rockchip_pcie_phy_probe,413	.driver		= {414		.name	= "rockchip-pcie-phy",415		.of_match_table = rockchip_pcie_phy_dt_ids,416	},417};418 419module_platform_driver(rockchip_pcie_driver);420 421MODULE_AUTHOR("Shawn Lin <shawn.lin@rock-chips.com>");422MODULE_DESCRIPTION("Rockchip PCIe PHY driver");423MODULE_LICENSE("GPL v2");424