1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2019 Xilinx, Inc. 4 */ 5 6 #include <linux/module.h> 7 #include <linux/nvmem-provider.h> 8 #include <linux/of.h> 9 #include <linux/platform_device.h> 10 #include <linux/firmware/xlnx-zynqmp.h> 11 12 #define SILICON_REVISION_MASK 0xF 13 14 struct zynqmp_nvmem_data { 15 struct device *dev; 16 struct nvmem_device *nvmem; 17 }; 18 19 static int zynqmp_nvmem_read(void *context, unsigned int offset, 20 void *val, size_t bytes) 21 { 22 int ret; 23 int idcode, version; 24 struct zynqmp_nvmem_data *priv = context; 25 26 ret = zynqmp_pm_get_chipid(&idcode, &version); 27 if (ret < 0) 28 return ret; 29 30 dev_dbg(priv->dev, "Read chipid val %x %x\n", idcode, version); 31 *(int *)val = version & SILICON_REVISION_MASK; 32 33 return 0; 34 } 35 36 static struct nvmem_config econfig = { 37 .name = "zynqmp-nvmem", 38 .owner = THIS_MODULE, 39 .word_size = 1, 40 .size = 1, 41 .read_only = true, 42 }; 43 44 static const struct of_device_id zynqmp_nvmem_match[] = { 45 { .compatible = "xlnx,zynqmp-nvmem-fw", }, 46 { /* sentinel */ }, 47 }; 48 MODULE_DEVICE_TABLE(of, zynqmp_nvmem_match); 49 50 static int zynqmp_nvmem_probe(struct platform_device *pdev) 51 { 52 struct device *dev = &pdev->dev; 53 struct zynqmp_nvmem_data *priv; 54 55 priv = devm_kzalloc(dev, sizeof(struct zynqmp_nvmem_data), GFP_KERNEL); 56 if (!priv) 57 return -ENOMEM; 58 59 priv->dev = dev; 60 econfig.dev = dev; 61 econfig.reg_read = zynqmp_nvmem_read; 62 econfig.priv = priv; 63 64 priv->nvmem = devm_nvmem_register(dev, &econfig); 65 66 return PTR_ERR_OR_ZERO(priv->nvmem); 67 } 68 69 static struct platform_driver zynqmp_nvmem_driver = { 70 .probe = zynqmp_nvmem_probe, 71 .driver = { 72 .name = "zynqmp-nvmem", 73 .of_match_table = zynqmp_nvmem_match, 74 }, 75 }; 76 77 module_platform_driver(zynqmp_nvmem_driver); 78 79 MODULE_AUTHOR("Michal Simek <michal.simek@amd.com>, Nava kishore Manne <nava.kishore.manne@amd.com>"); 80 MODULE_DESCRIPTION("ZynqMP NVMEM driver"); 81 MODULE_LICENSE("GPL"); 82