tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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.add_legacy_fixed_of_cells = true;
62 econfig.reg_read = zynqmp_nvmem_read;
63 econfig.priv = priv;
64
65 priv->nvmem = devm_nvmem_register(dev, &econfig);
66
67 return PTR_ERR_OR_ZERO(priv->nvmem);
68}
69
70static struct platform_driver zynqmp_nvmem_driver = {
71 .probe = zynqmp_nvmem_probe,
72 .driver = {
73 .name = "zynqmp-nvmem",
74 .of_match_table = zynqmp_nvmem_match,
75 },
76};
77
78module_platform_driver(zynqmp_nvmem_driver);
79
80MODULE_AUTHOR("Michal Simek <michal.simek@amd.com>, Nava kishore Manne <nava.kishore.manne@amd.com>");
81MODULE_DESCRIPTION("ZynqMP NVMEM driver");
82MODULE_LICENSE("GPL");