1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Renesas R-Car E-FUSE/OTP Driver 4 * 5 * Copyright (C) 2024 Glider bv 6 */ 7 8 #include <linux/device.h> 9 #include <linux/export.h> 10 #include <linux/io.h> 11 #include <linux/mod_devicetable.h> 12 #include <linux/nvmem-provider.h> 13 #include <linux/platform_device.h> 14 #include <linux/pm_runtime.h> 15 #include <linux/property.h> 16 17 struct rcar_fuse { 18 struct nvmem_keepout keepouts[2]; 19 struct nvmem_device *nvmem; 20 struct device *dev; 21 void __iomem *base; 22 }; 23 24 struct rcar_fuse_data { 25 unsigned int bank; /* 0: PFC + E-FUSE, 1: OPT_MEM + E-FUSE */ 26 unsigned int start; /* inclusive */ 27 unsigned int end; /* exclusive */ 28 }; 29 30 static int rcar_fuse_reg_read(void *priv, unsigned int offset, void *val, 31 size_t bytes) 32 { 33 struct rcar_fuse *fuse = priv; 34 int ret; 35 36 ret = pm_runtime_resume_and_get(fuse->dev); 37 if (ret < 0) 38 return ret; 39 40 __ioread32_copy(val, fuse->base + offset, bytes / 4); 41 42 pm_runtime_put(fuse->dev); 43 44 return 0; 45 } 46 47 static int rcar_fuse_probe(struct platform_device *pdev) 48 { 49 struct device *dev = &pdev->dev; 50 const struct rcar_fuse_data *data = device_get_match_data(dev); 51 struct nvmem_config config = { 52 .dev = dev, 53 .name = "rcar-fuse", 54 .id = NVMEM_DEVID_NONE, 55 .owner = THIS_MODULE, 56 .type = NVMEM_TYPE_OTP, 57 .read_only = true, 58 .root_only = true, 59 .reg_read = rcar_fuse_reg_read, 60 .word_size = 4, 61 .stride = 4, 62 }; 63 struct rcar_fuse *fuse; 64 struct resource *res; 65 int ret; 66 67 ret = devm_pm_runtime_enable(dev); 68 if (ret < 0) 69 return ret; 70 71 fuse = devm_kzalloc(dev, sizeof(*fuse), GFP_KERNEL); 72 if (!fuse) 73 return -ENOMEM; 74 75 fuse->base = devm_platform_get_and_ioremap_resource(pdev, data->bank, 76 &res); 77 if (IS_ERR(fuse->base)) 78 return PTR_ERR(fuse->base); 79 80 fuse->dev = dev; 81 fuse->keepouts[0].start = 0; 82 fuse->keepouts[0].end = data->start; 83 fuse->keepouts[1].start = data->end; 84 fuse->keepouts[1].end = resource_size(res); 85 86 config.keepout = fuse->keepouts; 87 config.nkeepout = ARRAY_SIZE(fuse->keepouts); 88 config.size = resource_size(res); 89 config.priv = fuse; 90 91 fuse->nvmem = devm_nvmem_register(dev, &config); 92 if (IS_ERR(fuse->nvmem)) 93 return dev_err_probe(dev, PTR_ERR(fuse->nvmem), 94 "Failed to register NVMEM device\n"); 95 96 return 0; 97 } 98 99 static const struct rcar_fuse_data rcar_fuse_v3u = { 100 .bank = 0, 101 .start = 0x0c0, 102 .end = 0x0e8, 103 }; 104 105 static const struct rcar_fuse_data rcar_fuse_s4 = { 106 .bank = 0, 107 .start = 0x0c0, 108 .end = 0x14c, 109 }; 110 111 static const struct rcar_fuse_data rcar_fuse_v4h = { 112 .bank = 1, 113 .start = 0x100, 114 .end = 0x1a0, 115 }; 116 117 static const struct rcar_fuse_data rcar_fuse_v4m = { 118 .bank = 1, 119 .start = 0x100, 120 .end = 0x110, 121 }; 122 123 static const struct of_device_id rcar_fuse_match[] = { 124 { .compatible = "renesas,r8a779a0-efuse", .data = &rcar_fuse_v3u }, 125 { .compatible = "renesas,r8a779f0-efuse", .data = &rcar_fuse_s4 }, 126 { .compatible = "renesas,r8a779g0-otp", .data = &rcar_fuse_v4h }, 127 { .compatible = "renesas,r8a779h0-otp", .data = &rcar_fuse_v4m }, 128 { /* sentinel */ } 129 }; 130 131 static struct platform_driver rcar_fuse_driver = { 132 .probe = rcar_fuse_probe, 133 .driver = { 134 .name = "rcar_fuse", 135 .of_match_table = rcar_fuse_match, 136 }, 137 }; 138 module_platform_driver(rcar_fuse_driver); 139 140 MODULE_DESCRIPTION("Renesas R-Car E-FUSE/OTP driver"); 141 MODULE_LICENSE("GPL"); 142 MODULE_AUTHOR("Geert Uytterhoeven"); 143