1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2023 Westermo Network Technologies AB 4 */ 5 6 #include <linux/device.h> 7 #include <linux/io.h> 8 #include <linux/module.h> 9 #include <linux/mod_devicetable.h> 10 #include <linux/nvmem-provider.h> 11 #include <linux/platform_device.h> 12 13 struct qoriq_efuse_priv { 14 void __iomem *base; 15 }; 16 17 static int qoriq_efuse_read(void *context, unsigned int offset, void *val, 18 size_t bytes) 19 { 20 struct qoriq_efuse_priv *priv = context; 21 22 /* .stride = 4 so offset is guaranteed to be aligned */ 23 __ioread32_copy(val, priv->base + offset, bytes / 4); 24 25 /* Ignore trailing bytes (there shouldn't be any) */ 26 27 return 0; 28 } 29 30 static int qoriq_efuse_probe(struct platform_device *pdev) 31 { 32 struct nvmem_config config = { 33 .dev = &pdev->dev, 34 .read_only = true, 35 .reg_read = qoriq_efuse_read, 36 .stride = sizeof(u32), 37 .word_size = sizeof(u32), 38 .name = "qoriq_efuse_read", 39 .id = NVMEM_DEVID_AUTO, 40 .root_only = true, 41 }; 42 struct qoriq_efuse_priv *priv; 43 struct nvmem_device *nvmem; 44 struct resource *res; 45 46 priv = devm_kzalloc(config.dev, sizeof(*priv), GFP_KERNEL); 47 if (!priv) 48 return -ENOMEM; 49 50 priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); 51 if (IS_ERR(priv->base)) 52 return PTR_ERR(priv->base); 53 54 config.size = resource_size(res); 55 config.priv = priv; 56 nvmem = devm_nvmem_register(config.dev, &config); 57 58 return PTR_ERR_OR_ZERO(nvmem); 59 } 60 61 static const struct of_device_id qoriq_efuse_of_match[] = { 62 { .compatible = "fsl,t1023-sfp", }, 63 {/* sentinel */}, 64 }; 65 MODULE_DEVICE_TABLE(of, qoriq_efuse_of_match); 66 67 static struct platform_driver qoriq_efuse_driver = { 68 .probe = qoriq_efuse_probe, 69 .driver = { 70 .name = "qoriq-efuse", 71 .of_match_table = qoriq_efuse_of_match, 72 }, 73 }; 74 module_platform_driver(qoriq_efuse_driver); 75 76 MODULE_AUTHOR("Richard Alpe <richard.alpe@bit42.se>"); 77 MODULE_DESCRIPTION("NXP QorIQ Security Fuse Processor (SFP) Reader"); 78 MODULE_LICENSE("GPL"); 79