diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/phy/ralink/phy-mt7621-pci.c | 360 |
1 files changed, 360 insertions, 0 deletions
diff --git a/drivers/phy/ralink/phy-mt7621-pci.c b/drivers/phy/ralink/phy-mt7621-pci.c new file mode 100644 index 000000000..85888ab2d --- /dev/null +++ b/drivers/phy/ralink/phy-mt7621-pci.c @@ -0,0 +1,360 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Mediatek MT7621 PCI PHY Driver + * Author: Sergio Paracuellos <sergio.paracuellos@gmail.com> + */ + +#include <dt-bindings/phy/phy.h> +#include <linux/clk.h> +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/phy/phy.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/sys_soc.h> + +#define RG_PE1_PIPE_REG 0x02c +#define RG_PE1_PIPE_RST BIT(12) +#define RG_PE1_PIPE_CMD_FRC BIT(4) + +#define RG_P0_TO_P1_WIDTH 0x100 +#define RG_PE1_H_LCDDS_REG 0x49c +#define RG_PE1_H_LCDDS_PCW GENMASK(30, 0) + +#define RG_PE1_FRC_H_XTAL_REG 0x400 +#define RG_PE1_FRC_H_XTAL_TYPE BIT(8) +#define RG_PE1_H_XTAL_TYPE GENMASK(10, 9) + +#define RG_PE1_FRC_PHY_REG 0x000 +#define RG_PE1_FRC_PHY_EN BIT(4) +#define RG_PE1_PHY_EN BIT(5) + +#define RG_PE1_H_PLL_REG 0x490 +#define RG_PE1_H_PLL_BC GENMASK(23, 22) +#define RG_PE1_H_PLL_BP GENMASK(21, 18) +#define RG_PE1_H_PLL_IR GENMASK(15, 12) +#define RG_PE1_H_PLL_IC GENMASK(11, 8) +#define RG_PE1_H_PLL_PREDIV GENMASK(7, 6) +#define RG_PE1_PLL_DIVEN GENMASK(3, 1) + +#define RG_PE1_H_PLL_FBKSEL_REG 0x4bc +#define RG_PE1_H_PLL_FBKSEL GENMASK(5, 4) + +#define RG_PE1_H_LCDDS_SSC_PRD_REG 0x4a4 +#define RG_PE1_H_LCDDS_SSC_PRD GENMASK(15, 0) + +#define RG_PE1_H_LCDDS_SSC_DELTA_REG 0x4a8 +#define RG_PE1_H_LCDDS_SSC_DELTA GENMASK(11, 0) +#define RG_PE1_H_LCDDS_SSC_DELTA1 GENMASK(27, 16) + +#define RG_PE1_LCDDS_CLK_PH_INV_REG 0x4a0 +#define RG_PE1_LCDDS_CLK_PH_INV BIT(5) + +#define RG_PE1_H_PLL_BR_REG 0x4ac +#define RG_PE1_H_PLL_BR GENMASK(18, 16) + +#define RG_PE1_MSTCKDIV_REG 0x414 +#define RG_PE1_MSTCKDIV GENMASK(7, 6) + +#define RG_PE1_FRC_MSTCKDIV BIT(5) + +#define MAX_PHYS 2 + +/** + * struct mt7621_pci_phy - Mt7621 Pcie PHY core + * @dev: pointer to device + * @regmap: kernel regmap pointer + * @phy: pointer to the kernel PHY device + * @sys_clk: pointer to the system XTAL clock + * @port_base: base register + * @has_dual_port: if the phy has dual ports. + * @bypass_pipe_rst: mark if 'mt7621_bypass_pipe_rst' + * needs to be executed. Depends on chip revision. + */ +struct mt7621_pci_phy { + struct device *dev; + struct regmap *regmap; + struct phy *phy; + struct clk *sys_clk; + void __iomem *port_base; + bool has_dual_port; + bool bypass_pipe_rst; +}; + +static inline void mt7621_phy_rmw(struct mt7621_pci_phy *phy, + u32 reg, u32 clr, u32 set) +{ + u32 val; + + /* + * We cannot use 'regmap_write_bits' here because internally + * 'set' is masked before is set to the value that will be + * written to the register. That way results in no reliable + * pci setup. Avoid to mask 'set' before set value to 'val' + * completely avoid the problem. + */ + regmap_read(phy->regmap, reg, &val); + val &= ~clr; + val |= set; + regmap_write(phy->regmap, reg, val); +} + +static void mt7621_bypass_pipe_rst(struct mt7621_pci_phy *phy) +{ + mt7621_phy_rmw(phy, RG_PE1_PIPE_REG, 0, RG_PE1_PIPE_RST); + mt7621_phy_rmw(phy, RG_PE1_PIPE_REG, 0, RG_PE1_PIPE_CMD_FRC); + + if (phy->has_dual_port) { + mt7621_phy_rmw(phy, RG_PE1_PIPE_REG + RG_P0_TO_P1_WIDTH, + 0, RG_PE1_PIPE_RST); + mt7621_phy_rmw(phy, RG_PE1_PIPE_REG + RG_P0_TO_P1_WIDTH, + 0, RG_PE1_PIPE_CMD_FRC); + } +} + +static int mt7621_set_phy_for_ssc(struct mt7621_pci_phy *phy) +{ + struct device *dev = phy->dev; + unsigned long clk_rate; + + clk_rate = clk_get_rate(phy->sys_clk); + if (!clk_rate) + return -EINVAL; + + /* Set PCIe Port PHY to disable SSC */ + /* Debug Xtal Type */ + mt7621_phy_rmw(phy, RG_PE1_FRC_H_XTAL_REG, + RG_PE1_FRC_H_XTAL_TYPE | RG_PE1_H_XTAL_TYPE, + RG_PE1_FRC_H_XTAL_TYPE | + FIELD_PREP(RG_PE1_H_XTAL_TYPE, 0x00)); + + /* disable port */ + mt7621_phy_rmw(phy, RG_PE1_FRC_PHY_REG, RG_PE1_PHY_EN, + RG_PE1_FRC_PHY_EN); + + if (phy->has_dual_port) { + mt7621_phy_rmw(phy, RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH, + RG_PE1_PHY_EN, RG_PE1_FRC_PHY_EN); + } + + if (clk_rate == 40000000) { /* 40MHz Xtal */ + /* Set Pre-divider ratio (for host mode) */ + mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG, RG_PE1_H_PLL_PREDIV, + FIELD_PREP(RG_PE1_H_PLL_PREDIV, 0x01)); + + dev_dbg(dev, "Xtal is 40MHz\n"); + } else if (clk_rate == 25000000) { /* 25MHz Xal */ + mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG, RG_PE1_H_PLL_PREDIV, + FIELD_PREP(RG_PE1_H_PLL_PREDIV, 0x00)); + + /* Select feedback clock */ + mt7621_phy_rmw(phy, RG_PE1_H_PLL_FBKSEL_REG, + RG_PE1_H_PLL_FBKSEL, + FIELD_PREP(RG_PE1_H_PLL_FBKSEL, 0x01)); + + /* DDS NCPO PCW (for host mode) */ + mt7621_phy_rmw(phy, RG_PE1_H_LCDDS_SSC_PRD_REG, + RG_PE1_H_LCDDS_SSC_PRD, + FIELD_PREP(RG_PE1_H_LCDDS_SSC_PRD, 0x00)); + + /* DDS SSC dither period control */ + mt7621_phy_rmw(phy, RG_PE1_H_LCDDS_SSC_PRD_REG, + RG_PE1_H_LCDDS_SSC_PRD, + FIELD_PREP(RG_PE1_H_LCDDS_SSC_PRD, 0x18d)); + + /* DDS SSC dither amplitude control */ + mt7621_phy_rmw(phy, RG_PE1_H_LCDDS_SSC_DELTA_REG, + RG_PE1_H_LCDDS_SSC_DELTA | + RG_PE1_H_LCDDS_SSC_DELTA1, + FIELD_PREP(RG_PE1_H_LCDDS_SSC_DELTA, 0x4a) | + FIELD_PREP(RG_PE1_H_LCDDS_SSC_DELTA1, 0x4a)); + + dev_dbg(dev, "Xtal is 25MHz\n"); + } else { /* 20MHz Xtal */ + mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG, RG_PE1_H_PLL_PREDIV, + FIELD_PREP(RG_PE1_H_PLL_PREDIV, 0x00)); + + dev_dbg(dev, "Xtal is 20MHz\n"); + } + + /* DDS clock inversion */ + mt7621_phy_rmw(phy, RG_PE1_LCDDS_CLK_PH_INV_REG, + RG_PE1_LCDDS_CLK_PH_INV, RG_PE1_LCDDS_CLK_PH_INV); + + /* Set PLL bits */ + mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG, + RG_PE1_H_PLL_BC | RG_PE1_H_PLL_BP | RG_PE1_H_PLL_IR | + RG_PE1_H_PLL_IC | RG_PE1_PLL_DIVEN, + FIELD_PREP(RG_PE1_H_PLL_BC, 0x02) | + FIELD_PREP(RG_PE1_H_PLL_BP, 0x06) | + FIELD_PREP(RG_PE1_H_PLL_IR, 0x02) | + FIELD_PREP(RG_PE1_H_PLL_IC, 0x01) | + FIELD_PREP(RG_PE1_PLL_DIVEN, 0x02)); + + mt7621_phy_rmw(phy, RG_PE1_H_PLL_BR_REG, RG_PE1_H_PLL_BR, + FIELD_PREP(RG_PE1_H_PLL_BR, 0x00)); + + if (clk_rate == 40000000) { /* 40MHz Xtal */ + /* set force mode enable of da_pe1_mstckdiv */ + mt7621_phy_rmw(phy, RG_PE1_MSTCKDIV_REG, + RG_PE1_MSTCKDIV | RG_PE1_FRC_MSTCKDIV, + FIELD_PREP(RG_PE1_MSTCKDIV, 0x01) | + RG_PE1_FRC_MSTCKDIV); + } + + return 0; +} + +static int mt7621_pci_phy_init(struct phy *phy) +{ + struct mt7621_pci_phy *mphy = phy_get_drvdata(phy); + + if (mphy->bypass_pipe_rst) + mt7621_bypass_pipe_rst(mphy); + + return mt7621_set_phy_for_ssc(mphy); +} + +static int mt7621_pci_phy_power_on(struct phy *phy) +{ + struct mt7621_pci_phy *mphy = phy_get_drvdata(phy); + + /* Enable PHY and disable force mode */ + mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG, + RG_PE1_FRC_PHY_EN, RG_PE1_PHY_EN); + + if (mphy->has_dual_port) { + mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH, + RG_PE1_FRC_PHY_EN, RG_PE1_PHY_EN); + } + + return 0; +} + +static int mt7621_pci_phy_power_off(struct phy *phy) +{ + struct mt7621_pci_phy *mphy = phy_get_drvdata(phy); + + /* Disable PHY */ + mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG, + RG_PE1_PHY_EN, RG_PE1_FRC_PHY_EN); + + if (mphy->has_dual_port) { + mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH, + RG_PE1_PHY_EN, RG_PE1_FRC_PHY_EN); + } + + return 0; +} + +static int mt7621_pci_phy_exit(struct phy *phy) +{ + return 0; +} + +static const struct phy_ops mt7621_pci_phy_ops = { + .init = mt7621_pci_phy_init, + .exit = mt7621_pci_phy_exit, + .power_on = mt7621_pci_phy_power_on, + .power_off = mt7621_pci_phy_power_off, + .owner = THIS_MODULE, +}; + +static struct phy *mt7621_pcie_phy_of_xlate(struct device *dev, + struct of_phandle_args *args) +{ + struct mt7621_pci_phy *mt7621_phy = dev_get_drvdata(dev); + + if (WARN_ON(args->args[0] >= MAX_PHYS)) + return ERR_PTR(-ENODEV); + + mt7621_phy->has_dual_port = args->args[0]; + + dev_dbg(dev, "PHY for 0x%px (dual port = %d)\n", + mt7621_phy->port_base, mt7621_phy->has_dual_port); + + return mt7621_phy->phy; +} + +static const struct soc_device_attribute mt7621_pci_quirks_match[] = { + { .soc_id = "mt7621", .revision = "E2" }, + { /* sentinel */ } +}; + +static const struct regmap_config mt7621_pci_phy_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .max_register = 0x700, +}; + +static int mt7621_pci_phy_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const struct soc_device_attribute *attr; + struct phy_provider *provider; + struct mt7621_pci_phy *phy; + + phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL); + if (!phy) + return -ENOMEM; + + attr = soc_device_match(mt7621_pci_quirks_match); + if (attr) + phy->bypass_pipe_rst = true; + + phy->dev = dev; + platform_set_drvdata(pdev, phy); + + phy->port_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(phy->port_base)) { + dev_err(dev, "failed to remap phy regs\n"); + return PTR_ERR(phy->port_base); + } + + phy->regmap = devm_regmap_init_mmio(phy->dev, phy->port_base, + &mt7621_pci_phy_regmap_config); + if (IS_ERR(phy->regmap)) + return PTR_ERR(phy->regmap); + + phy->phy = devm_phy_create(dev, dev->of_node, &mt7621_pci_phy_ops); + if (IS_ERR(phy->phy)) { + dev_err(dev, "failed to create phy\n"); + return PTR_ERR(phy->phy); + } + + phy->sys_clk = devm_clk_get(dev, NULL); + if (IS_ERR(phy->sys_clk)) { + dev_err(dev, "failed to get phy clock\n"); + return PTR_ERR(phy->sys_clk); + } + + phy_set_drvdata(phy->phy, phy); + + provider = devm_of_phy_provider_register(dev, mt7621_pcie_phy_of_xlate); + + return PTR_ERR_OR_ZERO(provider); +} + +static const struct of_device_id mt7621_pci_phy_ids[] = { + { .compatible = "mediatek,mt7621-pci-phy" }, + {}, +}; +MODULE_DEVICE_TABLE(of, mt7621_pci_phy_ids); + +static struct platform_driver mt7621_pci_phy_driver = { + .probe = mt7621_pci_phy_probe, + .driver = { + .name = "mt7621-pci-phy", + .of_match_table = mt7621_pci_phy_ids, + }, +}; + +builtin_platform_driver(mt7621_pci_phy_driver); + +MODULE_AUTHOR("Sergio Paracuellos <sergio.paracuellos@gmail.com>"); +MODULE_DESCRIPTION("MediaTek MT7621 PCIe PHY driver"); +MODULE_LICENSE("GPL v2"); |