1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * dwmac-sun55i.c - Allwinner sun55i GMAC200 specific glue layer 4 * 5 * Copyright (C) 2025 Chen-Yu Tsai <wens@csie.org> 6 * 7 * syscon parts taken from dwmac-sun8i.c, which is 8 * 9 * Copyright (C) 2017 Corentin Labbe <clabbe.montjoie@gmail.com> 10 */ 11 12 #include <linux/bitfield.h> 13 #include <linux/bits.h> 14 #include <linux/mfd/syscon.h> 15 #include <linux/module.h> 16 #include <linux/of.h> 17 #include <linux/phy.h> 18 #include <linux/platform_device.h> 19 #include <linux/regmap.h> 20 #include <linux/regulator/consumer.h> 21 #include <linux/stmmac.h> 22 23 #include "stmmac.h" 24 #include "stmmac_platform.h" 25 26 #define SYSCON_REG 0x34 27 28 /* RMII specific bits */ 29 #define SYSCON_RMII_EN BIT(13) /* 1: enable RMII (overrides EPIT) */ 30 /* Generic system control EMAC_CLK bits */ 31 #define SYSCON_ETXDC_MASK GENMASK(12, 10) 32 #define SYSCON_ERXDC_MASK GENMASK(9, 5) 33 /* EMAC PHY Interface Type */ 34 #define SYSCON_EPIT BIT(2) /* 1: RGMII, 0: MII */ 35 #define SYSCON_ETCS_MASK GENMASK(1, 0) 36 #define SYSCON_ETCS_MII 0x0 37 #define SYSCON_ETCS_EXT_GMII 0x1 38 #define SYSCON_ETCS_INT_GMII 0x2 39 40 static int sun55i_gmac200_set_syscon(struct device *dev, 41 struct plat_stmmacenet_data *plat) 42 { 43 struct device_node *node = dev->of_node; 44 struct regmap *regmap; 45 u32 val, reg = 0; 46 int ret; 47 48 regmap = syscon_regmap_lookup_by_phandle(node, "syscon"); 49 if (IS_ERR(regmap)) 50 return dev_err_probe(dev, PTR_ERR(regmap), "Unable to map syscon\n"); 51 52 if (!of_property_read_u32(node, "tx-internal-delay-ps", &val)) { 53 if (val % 100) 54 return dev_err_probe(dev, -EINVAL, 55 "tx-delay must be a multiple of 100ps\n"); 56 val /= 100; 57 dev_dbg(dev, "set tx-delay to %x\n", val); 58 if (!FIELD_FIT(SYSCON_ETXDC_MASK, val)) 59 return dev_err_probe(dev, -EINVAL, 60 "TX clock delay exceeds maximum (%u00ps > %lu00ps)\n", 61 val, FIELD_MAX(SYSCON_ETXDC_MASK)); 62 63 reg |= FIELD_PREP(SYSCON_ETXDC_MASK, val); 64 } 65 66 if (!of_property_read_u32(node, "rx-internal-delay-ps", &val)) { 67 if (val % 100) 68 return dev_err_probe(dev, -EINVAL, 69 "rx-delay must be a multiple of 100ps\n"); 70 val /= 100; 71 dev_dbg(dev, "set rx-delay to %x\n", val); 72 if (!FIELD_FIT(SYSCON_ERXDC_MASK, val)) 73 return dev_err_probe(dev, -EINVAL, 74 "RX clock delay exceeds maximum (%u00ps > %lu00ps)\n", 75 val, FIELD_MAX(SYSCON_ERXDC_MASK)); 76 77 reg |= FIELD_PREP(SYSCON_ERXDC_MASK, val); 78 } 79 80 switch (plat->phy_interface) { 81 case PHY_INTERFACE_MODE_MII: 82 /* default */ 83 break; 84 case PHY_INTERFACE_MODE_RGMII: 85 case PHY_INTERFACE_MODE_RGMII_ID: 86 case PHY_INTERFACE_MODE_RGMII_RXID: 87 case PHY_INTERFACE_MODE_RGMII_TXID: 88 reg |= SYSCON_EPIT | SYSCON_ETCS_INT_GMII; 89 break; 90 case PHY_INTERFACE_MODE_RMII: 91 reg |= SYSCON_RMII_EN; 92 break; 93 default: 94 return dev_err_probe(dev, -EINVAL, "Unsupported interface mode: %s", 95 phy_modes(plat->phy_interface)); 96 } 97 98 ret = regmap_write(regmap, SYSCON_REG, reg); 99 if (ret < 0) 100 return dev_err_probe(dev, ret, "Failed to write to syscon\n"); 101 102 return 0; 103 } 104 105 static int sun55i_gmac200_probe(struct platform_device *pdev) 106 { 107 struct plat_stmmacenet_data *plat_dat; 108 struct stmmac_resources stmmac_res; 109 struct device *dev = &pdev->dev; 110 struct clk *clk; 111 int ret; 112 113 ret = stmmac_get_platform_resources(pdev, &stmmac_res); 114 if (ret) 115 return ret; 116 117 plat_dat = devm_stmmac_probe_config_dt(pdev, stmmac_res.mac); 118 if (IS_ERR(plat_dat)) 119 return PTR_ERR(plat_dat); 120 121 /* BSP disables it */ 122 plat_dat->flags |= STMMAC_FLAG_SPH_DISABLE; 123 plat_dat->host_dma_width = 32; 124 125 ret = sun55i_gmac200_set_syscon(dev, plat_dat); 126 if (ret) 127 return ret; 128 129 clk = devm_clk_get_enabled(dev, "mbus"); 130 if (IS_ERR(clk)) 131 return dev_err_probe(dev, PTR_ERR(clk), 132 "Failed to get or enable MBUS clock\n"); 133 134 ret = devm_regulator_get_enable_optional(dev, "phy"); 135 if (ret) 136 return dev_err_probe(dev, ret, "Failed to get or enable PHY supply\n"); 137 138 return devm_stmmac_pltfr_probe(pdev, plat_dat, &stmmac_res); 139 } 140 141 static const struct of_device_id sun55i_gmac200_match[] = { 142 { .compatible = "allwinner,sun55i-a523-gmac200" }, 143 { } 144 }; 145 MODULE_DEVICE_TABLE(of, sun55i_gmac200_match); 146 147 static struct platform_driver sun55i_gmac200_driver = { 148 .probe = sun55i_gmac200_probe, 149 .driver = { 150 .name = "dwmac-sun55i", 151 .pm = &stmmac_pltfr_pm_ops, 152 .of_match_table = sun55i_gmac200_match, 153 }, 154 }; 155 module_platform_driver(sun55i_gmac200_driver); 156 157 MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>"); 158 MODULE_DESCRIPTION("Allwinner sun55i GMAC200 specific glue layer"); 159 MODULE_LICENSE("GPL"); 160