cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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zynqmp_nvmem.c (1853B)

      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");