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
14struct zynqmp_nvmem_data {
15	struct device *dev;
16	struct nvmem_device *nvmem;
17};
18
19static 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
36static 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
44static const struct of_device_id zynqmp_nvmem_match[] = {
45	{ .compatible = "xlnx,zynqmp-nvmem-fw", },
46	{ /* sentinel */ },
47};
48MODULE_DEVICE_TABLE(of, zynqmp_nvmem_match);
49
50static 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
69static 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
77module_platform_driver(zynqmp_nvmem_driver);
78
79MODULE_AUTHOR("Michal Simek <michal.simek@xilinx.com>, Nava kishore Manne <navam@xilinx.com>");
80MODULE_DESCRIPTION("ZynqMP NVMEM driver");
81MODULE_LICENSE("GPL");
82