diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/phy/lantiq/phy-lantiq-vrx200-pcie.c | 493 |
1 files changed, 493 insertions, 0 deletions
diff --git a/drivers/phy/lantiq/phy-lantiq-vrx200-pcie.c b/drivers/phy/lantiq/phy-lantiq-vrx200-pcie.c new file mode 100644 index 000000000..ef93bf2cb --- /dev/null +++ b/drivers/phy/lantiq/phy-lantiq-vrx200-pcie.c @@ -0,0 +1,493 @@ +// 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 */ + ret = ltq_vrx200_pcie_phy_wait_for_pll(phy); + if (ret) + 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 const 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; + void __iomem *base; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + base = devm_platform_ioremap_resource(pdev, 0); + 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"); |