1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * i.MX9 OCOTP fusebox driver 4 * 5 * Copyright 2023 NXP 6 */ 7 8 #include <linux/device.h> 9 #include <linux/io.h> 10 #include <linux/module.h> 11 #include <linux/nvmem-provider.h> 12 #include <linux/of.h> 13 #include <linux/platform_device.h> 14 #include <linux/slab.h> 15 16 enum fuse_type { 17 FUSE_FSB = BIT(0), 18 FUSE_ELE = BIT(1), 19 FUSE_ECC = BIT(2), 20 FUSE_INVALID = -1 21 }; 22 23 struct ocotp_map_entry { 24 u32 start; /* start word */ 25 u32 num; /* num words */ 26 enum fuse_type type; 27 }; 28 29 struct ocotp_devtype_data { 30 u32 reg_off; 31 char *name; 32 u32 size; 33 u32 num_entry; 34 u32 flag; 35 nvmem_reg_read_t reg_read; 36 struct ocotp_map_entry entry[]; 37 }; 38 39 struct imx_ocotp_priv { 40 struct device *dev; 41 void __iomem *base; 42 struct nvmem_config config; 43 struct mutex lock; 44 const struct ocotp_devtype_data *data; 45 }; 46 47 static enum fuse_type imx_ocotp_fuse_type(void *context, u32 index) 48 { 49 struct imx_ocotp_priv *priv = context; 50 const struct ocotp_devtype_data *data = priv->data; 51 u32 start, end; 52 int i; 53 54 for (i = 0; i < data->num_entry; i++) { 55 start = data->entry[i].start; 56 end = data->entry[i].start + data->entry[i].num; 57 58 if (index >= start && index < end) 59 return data->entry[i].type; 60 } 61 62 return FUSE_INVALID; 63 } 64 65 static int imx_ocotp_reg_read(void *context, unsigned int offset, void *val, size_t bytes) 66 { 67 struct imx_ocotp_priv *priv = context; 68 void __iomem *reg = priv->base + priv->data->reg_off; 69 u32 count, index, num_bytes; 70 enum fuse_type type; 71 u32 *buf; 72 void *p; 73 int i; 74 75 index = offset; 76 num_bytes = round_up(bytes, 4); 77 count = num_bytes >> 2; 78 79 if (count > ((priv->data->size >> 2) - index)) 80 count = (priv->data->size >> 2) - index; 81 82 p = kzalloc(num_bytes, GFP_KERNEL); 83 if (!p) 84 return -ENOMEM; 85 86 mutex_lock(&priv->lock); 87 88 buf = p; 89 90 for (i = index; i < (index + count); i++) { 91 type = imx_ocotp_fuse_type(context, i); 92 if (type == FUSE_INVALID || type == FUSE_ELE) { 93 *buf++ = 0; 94 continue; 95 } 96 97 if (type & FUSE_ECC) 98 *buf++ = readl_relaxed(reg + (i << 2)) & GENMASK(15, 0); 99 else 100 *buf++ = readl_relaxed(reg + (i << 2)); 101 } 102 103 memcpy(val, (u8 *)p, bytes); 104 105 mutex_unlock(&priv->lock); 106 107 kfree(p); 108 109 return 0; 110 }; 111 112 static int imx_ele_ocotp_probe(struct platform_device *pdev) 113 { 114 struct device *dev = &pdev->dev; 115 struct imx_ocotp_priv *priv; 116 struct nvmem_device *nvmem; 117 118 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 119 if (!priv) 120 return -ENOMEM; 121 122 priv->data = of_device_get_match_data(dev); 123 124 priv->base = devm_platform_ioremap_resource(pdev, 0); 125 if (IS_ERR(priv->base)) 126 return PTR_ERR(priv->base); 127 128 priv->config.dev = dev; 129 priv->config.name = "ELE-OCOTP"; 130 priv->config.id = NVMEM_DEVID_AUTO; 131 priv->config.owner = THIS_MODULE; 132 priv->config.size = priv->data->size; 133 priv->config.reg_read = priv->data->reg_read; 134 priv->config.word_size = 4; 135 priv->config.stride = 1; 136 priv->config.priv = priv; 137 priv->config.read_only = true; 138 mutex_init(&priv->lock); 139 140 nvmem = devm_nvmem_register(dev, &priv->config); 141 if (IS_ERR(nvmem)) 142 return PTR_ERR(nvmem); 143 144 return 0; 145 } 146 147 static const struct ocotp_devtype_data imx93_ocotp_data = { 148 .reg_off = 0x8000, 149 .reg_read = imx_ocotp_reg_read, 150 .size = 2048, 151 .num_entry = 6, 152 .entry = { 153 { 0, 52, FUSE_FSB }, 154 { 63, 1, FUSE_ELE}, 155 { 128, 16, FUSE_ELE }, 156 { 182, 1, FUSE_ELE }, 157 { 188, 1, FUSE_ELE }, 158 { 312, 200, FUSE_FSB } 159 }, 160 }; 161 162 static const struct ocotp_devtype_data imx95_ocotp_data = { 163 .reg_off = 0x8000, 164 .reg_read = imx_ocotp_reg_read, 165 .size = 2048, 166 .num_entry = 12, 167 .entry = { 168 { 0, 1, FUSE_FSB | FUSE_ECC }, 169 { 7, 1, FUSE_FSB | FUSE_ECC }, 170 { 9, 3, FUSE_FSB | FUSE_ECC }, 171 { 12, 24, FUSE_FSB }, 172 { 36, 2, FUSE_FSB | FUSE_ECC }, 173 { 38, 14, FUSE_FSB }, 174 { 63, 1, FUSE_ELE }, 175 { 128, 16, FUSE_ELE }, 176 { 188, 1, FUSE_ELE }, 177 { 317, 2, FUSE_FSB | FUSE_ECC }, 178 { 320, 7, FUSE_FSB }, 179 { 328, 184, FUSE_FSB } 180 }, 181 }; 182 183 static const struct of_device_id imx_ele_ocotp_dt_ids[] = { 184 { .compatible = "fsl,imx93-ocotp", .data = &imx93_ocotp_data, }, 185 { .compatible = "fsl,imx95-ocotp", .data = &imx95_ocotp_data, }, 186 {}, 187 }; 188 MODULE_DEVICE_TABLE(of, imx_ele_ocotp_dt_ids); 189 190 static struct platform_driver imx_ele_ocotp_driver = { 191 .driver = { 192 .name = "imx_ele_ocotp", 193 .of_match_table = imx_ele_ocotp_dt_ids, 194 }, 195 .probe = imx_ele_ocotp_probe, 196 }; 197 module_platform_driver(imx_ele_ocotp_driver); 198 199 MODULE_DESCRIPTION("i.MX OCOTP/ELE driver"); 200 MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>"); 201 MODULE_LICENSE("GPL"); 202