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 const struct zynqmp_eemi_ops *eemi_ops; 20 21 static int zynqmp_nvmem_read(void *context, unsigned int offset, 22 void *val, size_t bytes) 23 { 24 int ret; 25 int idcode, version; 26 struct zynqmp_nvmem_data *priv = context; 27 28 if (!eemi_ops->get_chipid) 29 return -ENXIO; 30 31 ret = eemi_ops->get_chipid(&idcode, &version); 32 if (ret < 0) 33 return ret; 34 35 dev_dbg(priv->dev, "Read chipid val %x %x\n", idcode, version); 36 *(int *)val = version & SILICON_REVISION_MASK; 37 38 return 0; 39 } 40 41 static struct nvmem_config econfig = { 42 .name = "zynqmp-nvmem", 43 .owner = THIS_MODULE, 44 .word_size = 1, 45 .size = 1, 46 .read_only = true, 47 }; 48 49 static const struct of_device_id zynqmp_nvmem_match[] = { 50 { .compatible = "xlnx,zynqmp-nvmem-fw", }, 51 { /* sentinel */ }, 52 }; 53 MODULE_DEVICE_TABLE(of, zynqmp_nvmem_match); 54 55 static int zynqmp_nvmem_probe(struct platform_device *pdev) 56 { 57 struct device *dev = &pdev->dev; 58 struct zynqmp_nvmem_data *priv; 59 60 priv = devm_kzalloc(dev, sizeof(struct zynqmp_nvmem_data), GFP_KERNEL); 61 if (!priv) 62 return -ENOMEM; 63 64 eemi_ops = zynqmp_pm_get_eemi_ops(); 65 if (IS_ERR(eemi_ops)) 66 return PTR_ERR(eemi_ops); 67 68 priv->dev = dev; 69 econfig.dev = dev; 70 econfig.reg_read = zynqmp_nvmem_read; 71 econfig.priv = priv; 72 73 priv->nvmem = devm_nvmem_register(dev, &econfig); 74 75 return PTR_ERR_OR_ZERO(priv->nvmem); 76 } 77 78 static struct platform_driver zynqmp_nvmem_driver = { 79 .probe = zynqmp_nvmem_probe, 80 .driver = { 81 .name = "zynqmp-nvmem", 82 .of_match_table = zynqmp_nvmem_match, 83 }, 84 }; 85 86 module_platform_driver(zynqmp_nvmem_driver); 87 88 MODULE_AUTHOR("Michal Simek <michal.simek@xilinx.com>, Nava kishore Manne <navam@xilinx.com>"); 89 MODULE_DESCRIPTION("ZynqMP NVMEM driver"); 90 MODULE_LICENSE("GPL"); 91