--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PCIe PHY driver for Lantiq VRX200 and ARX300 SoCs.
+ *
+ * Copyright (C) 2019 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
+ *
+ * Based on the BSP (called "UGW") driver:
+ * Copyright (C) 2009-2015 Lei Chuanhua <chuanhua.lei@lantiq.com>
+ * Copyright (C) 2016 Intel Corporation
+ *
+ * TODO: PHY modes other than 36MHz (without "SSC")
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/delay.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>
+
+#include <dt-bindings/phy/phy-lantiq-vrx200-pcie.h>
+
+#define PCIE_PHY_PLL_CTRL1 0x44
+
+#define PCIE_PHY_PLL_CTRL2 0x46
+#define PCIE_PHY_PLL_CTRL2_CONST_SDM_MASK GENMASK(7, 0)
+#define PCIE_PHY_PLL_CTRL2_CONST_SDM_EN BIT(8)
+#define PCIE_PHY_PLL_CTRL2_PLL_SDM_EN BIT(9)
+
+#define PCIE_PHY_PLL_CTRL3 0x48
+#define PCIE_PHY_PLL_CTRL3_EXT_MMD_DIV_RATIO_EN BIT(1)
+#define PCIE_PHY_PLL_CTRL3_EXT_MMD_DIV_RATIO_MASK GENMASK(6, 4)
+
+#define PCIE_PHY_PLL_CTRL4 0x4a
+#define PCIE_PHY_PLL_CTRL5 0x4c
+#define PCIE_PHY_PLL_CTRL6 0x4e
+#define PCIE_PHY_PLL_CTRL7 0x50
+#define PCIE_PHY_PLL_A_CTRL1 0x52
+
+#define PCIE_PHY_PLL_A_CTRL2 0x54
+#define PCIE_PHY_PLL_A_CTRL2_LF_MODE_EN BIT(14)
+
+#define PCIE_PHY_PLL_A_CTRL3 0x56
+#define PCIE_PHY_PLL_A_CTRL3_MMD_MASK GENMASK(15, 13)
+
+#define PCIE_PHY_PLL_STATUS 0x58
+
+#define PCIE_PHY_TX1_CTRL1 0x60
+#define PCIE_PHY_TX1_CTRL1_FORCE_EN BIT(3)
+#define PCIE_PHY_TX1_CTRL1_LOAD_EN BIT(4)
+
+#define PCIE_PHY_TX1_CTRL2 0x62
+#define PCIE_PHY_TX1_CTRL3 0x64
+#define PCIE_PHY_TX1_A_CTRL1 0x66
+#define PCIE_PHY_TX1_A_CTRL2 0x68
+#define PCIE_PHY_TX1_MOD1 0x6a
+#define PCIE_PHY_TX1_MOD2 0x6c
+#define PCIE_PHY_TX1_MOD3 0x6e
+
+#define PCIE_PHY_TX2_CTRL1 0x70
+#define PCIE_PHY_TX2_CTRL1_LOAD_EN BIT(4)
+
+#define PCIE_PHY_TX2_CTRL2 0x72
+#define PCIE_PHY_TX2_A_CTRL1 0x76
+#define PCIE_PHY_TX2_A_CTRL2 0x78
+#define PCIE_PHY_TX2_MOD1 0x7a
+#define PCIE_PHY_TX2_MOD2 0x7c
+#define PCIE_PHY_TX2_MOD3 0x7e
+
+#define PCIE_PHY_RX1_CTRL1 0xa0
+#define PCIE_PHY_RX1_CTRL1_LOAD_EN BIT(1)
+
+#define PCIE_PHY_RX1_CTRL2 0xa2
+#define PCIE_PHY_RX1_CDR 0xa4
+#define PCIE_PHY_RX1_EI 0xa6
+#define PCIE_PHY_RX1_A_CTRL 0xaa
+
+struct ltq_vrx200_pcie_phy_priv {
+ struct phy *phy;
+ unsigned int mode;
+ struct device *dev;
+ struct regmap *phy_regmap;
+ struct regmap *rcu_regmap;
+ struct clk *pdi_clk;
+ struct clk *phy_clk;
+ struct reset_control *phy_reset;
+ struct reset_control *pcie_reset;
+ u32 rcu_ahb_endian_offset;
+ u32 rcu_ahb_endian_big_endian_mask;
+};
+
+static void ltq_vrx200_pcie_phy_common_setup(struct phy *phy)
+{
+ struct ltq_vrx200_pcie_phy_priv *priv = phy_get_drvdata(phy);
+
+ /* PLL Setting */
+ regmap_write(priv->phy_regmap, PCIE_PHY_PLL_A_CTRL1, 0x120e);
+
+ /* increase the bias reference voltage */
+ regmap_write(priv->phy_regmap, PCIE_PHY_PLL_A_CTRL2, 0x39d7);
+ regmap_write(priv->phy_regmap, PCIE_PHY_PLL_A_CTRL3, 0x0900);
+
+ /* Endcnt */
+ regmap_write(priv->phy_regmap, PCIE_PHY_RX1_EI, 0x0004);
+ regmap_write(priv->phy_regmap, PCIE_PHY_RX1_A_CTRL, 0x6803);
+
+ regmap_update_bits(priv->phy_regmap, PCIE_PHY_TX1_CTRL1,
+ PCIE_PHY_TX1_CTRL1_FORCE_EN,
+ PCIE_PHY_TX1_CTRL1_FORCE_EN);
+
+ /* predrv_ser_en */
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX1_A_CTRL2, 0x0706);
+
+ /* ctrl_lim */
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX1_CTRL3, 0x1fff);
+
+ /* ctrl */
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX1_A_CTRL1, 0x0810);
+
+ /* predrv_ser_en */
+ regmap_update_bits(priv->phy_regmap, PCIE_PHY_TX2_A_CTRL2, 0x7f00,
+ 0x4700);
+
+ /* RTERM */
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX1_CTRL2, 0x2e00);
+
+ /* Improved 100MHz clock output */
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX2_CTRL2, 0x3096);
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX2_A_CTRL2, 0x4707);
+
+ /* Reduced CDR BW to avoid glitches */
+ regmap_write(priv->phy_regmap, PCIE_PHY_RX1_CDR, 0x0235);
+}
+
+static void pcie_phy_36mhz_mode_setup(struct phy *phy)
+{
+ struct ltq_vrx200_pcie_phy_priv *priv = phy_get_drvdata(phy);
+
+ regmap_update_bits(priv->phy_regmap, PCIE_PHY_PLL_CTRL3,
+ PCIE_PHY_PLL_CTRL3_EXT_MMD_DIV_RATIO_EN, 0x0000);
+
+ regmap_update_bits(priv->phy_regmap, PCIE_PHY_PLL_CTRL3,
+ PCIE_PHY_PLL_CTRL3_EXT_MMD_DIV_RATIO_MASK, 0x0000);
+
+ regmap_update_bits(priv->phy_regmap, PCIE_PHY_PLL_CTRL2,
+ PCIE_PHY_PLL_CTRL2_PLL_SDM_EN,
+ PCIE_PHY_PLL_CTRL2_PLL_SDM_EN);
+
+ regmap_update_bits(priv->phy_regmap, PCIE_PHY_PLL_CTRL2,
+ PCIE_PHY_PLL_CTRL2_CONST_SDM_EN,
+ PCIE_PHY_PLL_CTRL2_CONST_SDM_EN);
+
+ regmap_update_bits(priv->phy_regmap, PCIE_PHY_PLL_A_CTRL3,
+ PCIE_PHY_PLL_A_CTRL3_MMD_MASK,
+ FIELD_PREP(PCIE_PHY_PLL_A_CTRL3_MMD_MASK, 0x1));
+
+ regmap_update_bits(priv->phy_regmap, PCIE_PHY_PLL_A_CTRL2,
+ PCIE_PHY_PLL_A_CTRL2_LF_MODE_EN, 0x0000);
+
+ /* const_sdm */
+ regmap_write(priv->phy_regmap, PCIE_PHY_PLL_CTRL1, 0x38e4);
+
+ regmap_update_bits(priv->phy_regmap, PCIE_PHY_PLL_CTRL2,
+ PCIE_PHY_PLL_CTRL2_CONST_SDM_MASK,
+ FIELD_PREP(PCIE_PHY_PLL_CTRL2_CONST_SDM_MASK,
+ 0xee));
+
+ /* pllmod */
+ regmap_write(priv->phy_regmap, PCIE_PHY_PLL_CTRL7, 0x0002);
+ regmap_write(priv->phy_regmap, PCIE_PHY_PLL_CTRL6, 0x3a04);
+ regmap_write(priv->phy_regmap, PCIE_PHY_PLL_CTRL5, 0xfae3);
+ regmap_write(priv->phy_regmap, PCIE_PHY_PLL_CTRL4, 0x1b72);
+}
+
+static int ltq_vrx200_pcie_phy_wait_for_pll(struct phy *phy)
+{
+ struct ltq_vrx200_pcie_phy_priv *priv = phy_get_drvdata(phy);
+ unsigned int tmp;
+ int ret;
+
+ ret = regmap_read_poll_timeout(priv->phy_regmap, PCIE_PHY_PLL_STATUS,
+ tmp, ((tmp & 0x0070) == 0x0070), 10,
+ 10000);
+ if (ret) {
+ dev_err(priv->dev, "PLL Link timeout, PLL status = 0x%04x\n",
+ tmp);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void ltq_vrx200_pcie_phy_apply_workarounds(struct phy *phy)
+{
+ struct ltq_vrx200_pcie_phy_priv *priv = phy_get_drvdata(phy);
+ static const struct reg_default slices[] = {
+ {
+ .reg = PCIE_PHY_TX1_CTRL1,
+ .def = PCIE_PHY_TX1_CTRL1_LOAD_EN,
+ },
+ {
+ .reg = PCIE_PHY_TX2_CTRL1,
+ .def = PCIE_PHY_TX2_CTRL1_LOAD_EN,
+ },
+ {
+ .reg = PCIE_PHY_RX1_CTRL1,
+ .def = PCIE_PHY_RX1_CTRL1_LOAD_EN,
+ }
+ };
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(slices); i++) {
+ /* enable load_en */
+ regmap_update_bits(priv->phy_regmap, slices[i].reg,
+ slices[i].def, slices[i].def);
+
+ udelay(1);
+
+ /* disable load_en */
+ regmap_update_bits(priv->phy_regmap, slices[i].reg,
+ slices[i].def, 0x0);
+ }
+
+ for (i = 0; i < 5; i++) {
+ /* TX2 modulation */
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX2_MOD1, 0x1ffe);
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX2_MOD2, 0xfffe);
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX2_MOD3, 0x0601);
+ usleep_range(1000, 2000);
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX2_MOD3, 0x0001);
+
+ /* TX1 modulation */
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX1_MOD1, 0x1ffe);
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX1_MOD2, 0xfffe);
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX1_MOD3, 0x0601);
+ usleep_range(1000, 2000);
+ regmap_write(priv->phy_regmap, PCIE_PHY_TX1_MOD3, 0x0001);
+ }
+}
+
+static int ltq_vrx200_pcie_phy_init(struct phy *phy)
+{
+ struct ltq_vrx200_pcie_phy_priv *priv = phy_get_drvdata(phy);
+ int ret;
+
+ if (of_device_is_big_endian(priv->dev->of_node))
+ regmap_update_bits(priv->rcu_regmap,
+ priv->rcu_ahb_endian_offset,
+ priv->rcu_ahb_endian_big_endian_mask,
+ priv->rcu_ahb_endian_big_endian_mask);
+ else
+ regmap_update_bits(priv->rcu_regmap,
+ priv->rcu_ahb_endian_offset,
+ priv->rcu_ahb_endian_big_endian_mask, 0x0);
+
+ ret = reset_control_assert(priv->phy_reset);
+ if (ret)
+ goto err;
+
+ udelay(1);
+
+ ret = reset_control_deassert(priv->phy_reset);
+ if (ret)
+ goto err;
+
+ udelay(1);
+
+ ret = reset_control_deassert(priv->pcie_reset);
+ if (ret)
+ goto err_assert_phy_reset;
+
+ /* Make sure PHY PLL is stable */
+ usleep_range(20, 40);
+
+ return 0;
+
+err_assert_phy_reset:
+ reset_control_assert(priv->phy_reset);
+err:
+ return ret;
+}
+
+static int ltq_vrx200_pcie_phy_exit(struct phy *phy)
+{
+ struct ltq_vrx200_pcie_phy_priv *priv = phy_get_drvdata(phy);
+ int ret;
+
+ ret = reset_control_assert(priv->pcie_reset);
+ if (ret)
+ return ret;
+
+ ret = reset_control_assert(priv->phy_reset);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int ltq_vrx200_pcie_phy_power_on(struct phy *phy)
+{
+ struct ltq_vrx200_pcie_phy_priv *priv = phy_get_drvdata(phy);
+ int ret;
+
+ /* Enable PDI to access PCIe PHY register */
+ ret = clk_prepare_enable(priv->pdi_clk);
+ if (ret)
+ goto err;
+
+ /* Configure PLL and PHY clock */
+ ltq_vrx200_pcie_phy_common_setup(phy);
+
+ pcie_phy_36mhz_mode_setup(phy);
+
+ /* Enable the PCIe PHY and make PLL setting take effect */
+ ret = clk_prepare_enable(priv->phy_clk);
+ if (ret)
+ goto err_disable_pdi_clk;
+
+ /* Check if we are in "startup ready" status */
+ if (ltq_vrx200_pcie_phy_wait_for_pll(phy) != 0)
+ goto err_disable_phy_clk;
+
+ ltq_vrx200_pcie_phy_apply_workarounds(phy);
+
+ return 0;
+
+err_disable_phy_clk:
+ clk_disable_unprepare(priv->phy_clk);
+err_disable_pdi_clk:
+ clk_disable_unprepare(priv->pdi_clk);
+err:
+ return ret;
+}
+
+static int ltq_vrx200_pcie_phy_power_off(struct phy *phy)
+{
+ struct ltq_vrx200_pcie_phy_priv *priv = phy_get_drvdata(phy);
+
+ clk_disable_unprepare(priv->phy_clk);
+ clk_disable_unprepare(priv->pdi_clk);
+
+ return 0;
+}
+
+static struct phy_ops ltq_vrx200_pcie_phy_ops = {
+ .init = ltq_vrx200_pcie_phy_init,
+ .exit = ltq_vrx200_pcie_phy_exit,
+ .power_on = ltq_vrx200_pcie_phy_power_on,
+ .power_off = ltq_vrx200_pcie_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static struct phy *ltq_vrx200_pcie_phy_xlate(struct device *dev,
+ struct of_phandle_args *args)
+{
+ struct ltq_vrx200_pcie_phy_priv *priv = dev_get_drvdata(dev);
+ unsigned int mode;
+
+ if (args->args_count != 1) {
+ dev_err(dev, "invalid number of arguments\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ mode = args->args[0];
+
+ switch (mode) {
+ case LANTIQ_PCIE_PHY_MODE_36MHZ:
+ priv->mode = mode;
+ break;
+
+ case LANTIQ_PCIE_PHY_MODE_25MHZ:
+ case LANTIQ_PCIE_PHY_MODE_25MHZ_SSC:
+ case LANTIQ_PCIE_PHY_MODE_36MHZ_SSC:
+ case LANTIQ_PCIE_PHY_MODE_100MHZ:
+ case LANTIQ_PCIE_PHY_MODE_100MHZ_SSC:
+ dev_err(dev, "PHY mode not implemented yet: %u\n", mode);
+ return ERR_PTR(-EINVAL);
+
+ default:
+ dev_err(dev, "invalid PHY mode %u\n", mode);
+ return ERR_PTR(-EINVAL);
+ };
+
+ return priv->phy;
+}
+
+static int ltq_vrx200_pcie_phy_probe(struct platform_device *pdev)
+{
+ static const struct regmap_config regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 16,
+ .reg_stride = 2,
+ .max_register = PCIE_PHY_RX1_A_CTRL,
+ };
+ struct ltq_vrx200_pcie_phy_priv *priv;
+ struct device *dev = &pdev->dev;
+ struct phy_provider *provider;
+ struct resource *res;
+ void __iomem *base;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ priv->phy_regmap = devm_regmap_init_mmio(dev, base, ®map_config);
+ if (IS_ERR(priv->phy_regmap))
+ return PTR_ERR(priv->phy_regmap);
+
+ priv->rcu_regmap = syscon_regmap_lookup_by_phandle(dev->of_node,
+ "lantiq,rcu");
+ if (IS_ERR(priv->rcu_regmap))
+ return PTR_ERR(priv->rcu_regmap);
+
+ ret = device_property_read_u32(dev, "lantiq,rcu-endian-offset",
+ &priv->rcu_ahb_endian_offset);
+ if (ret) {
+ dev_err(dev,
+ "failed to parse the 'lantiq,rcu-endian-offset' property\n");
+ return ret;
+ }
+
+ ret = device_property_read_u32(dev, "lantiq,rcu-big-endian-mask",
+ &priv->rcu_ahb_endian_big_endian_mask);
+ if (ret) {
+ dev_err(dev,
+ "failed to parse the 'lantiq,rcu-big-endian-mask' property\n");
+ return ret;
+ }
+
+ priv->pdi_clk = devm_clk_get(dev, "pdi");
+ if (IS_ERR(priv->pdi_clk))
+ return PTR_ERR(priv->pdi_clk);
+
+ priv->phy_clk = devm_clk_get(dev, "phy");
+ if (IS_ERR(priv->phy_clk))
+ return PTR_ERR(priv->phy_clk);
+
+ priv->phy_reset = devm_reset_control_get_exclusive(dev, "phy");
+ if (IS_ERR(priv->phy_reset))
+ return PTR_ERR(priv->phy_reset);
+
+ priv->pcie_reset = devm_reset_control_get_shared(dev, "pcie");
+ if (IS_ERR(priv->pcie_reset))
+ return PTR_ERR(priv->pcie_reset);
+
+ priv->dev = dev;
+
+ priv->phy = devm_phy_create(dev, dev->of_node,
+ <q_vrx200_pcie_phy_ops);
+ if (IS_ERR(priv->phy)) {
+ dev_err(dev, "failed to create PHY\n");
+ return PTR_ERR(priv->phy);
+ }
+
+ phy_set_drvdata(priv->phy, priv);
+ dev_set_drvdata(dev, priv);
+
+ provider = devm_of_phy_provider_register(dev,
+ ltq_vrx200_pcie_phy_xlate);
+
+ return PTR_ERR_OR_ZERO(provider);
+}
+
+static const struct of_device_id ltq_vrx200_pcie_phy_of_match[] = {
+ { .compatible = "lantiq,vrx200-pcie-phy", },
+ { .compatible = "lantiq,arx300-pcie-phy", },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, ltq_vrx200_pcie_phy_of_match);
+
+static struct platform_driver ltq_vrx200_pcie_phy_driver = {
+ .probe = ltq_vrx200_pcie_phy_probe,
+ .driver = {
+ .name = "ltq-vrx200-pcie-phy",
+ .of_match_table = ltq_vrx200_pcie_phy_of_match,
+ }
+};
+module_platform_driver(ltq_vrx200_pcie_phy_driver);
+
+MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
+MODULE_DESCRIPTION("Lantiq VRX200 and ARX300 PCIe PHY driver");
+MODULE_LICENSE("GPL v2");
projects / platform / kernel / linux-starfive.git / commitdiff