1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Copyright (c) 2015, Christoph Hellwig.
 4 * Copyright (c) 2015, Intel Corporation.
 5 */
 6#include <linux/platform_device.h>
 7#include <linux/memory_hotplug.h>
 8#include <linux/libnvdimm.h>
 9#include <linux/module.h>
10#include <linux/numa.h>
11
12static int e820_pmem_remove(struct platform_device *pdev)
13{
14	struct nvdimm_bus *nvdimm_bus = platform_get_drvdata(pdev);
15
16	nvdimm_bus_unregister(nvdimm_bus);
17	return 0;
18}
19
20static int e820_register_one(struct resource *res, void *data)
21{
22	struct nd_region_desc ndr_desc;
23	struct nvdimm_bus *nvdimm_bus = data;
24	int nid = phys_to_target_node(res->start);
25
26	memset(&ndr_desc, 0, sizeof(ndr_desc));
27	ndr_desc.res = res;
28	ndr_desc.numa_node = numa_map_to_online_node(nid);
29	ndr_desc.target_node = nid;
30	set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
31	if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc))
32		return -ENXIO;
33	return 0;
34}
35
36static int e820_pmem_probe(struct platform_device *pdev)
37{
38	static struct nvdimm_bus_descriptor nd_desc;
39	struct device *dev = &pdev->dev;
40	struct nvdimm_bus *nvdimm_bus;
41	int rc = -ENXIO;
42
43	nd_desc.provider_name = "e820";
44	nd_desc.module = THIS_MODULE;
45	nvdimm_bus = nvdimm_bus_register(dev, &nd_desc);
46	if (!nvdimm_bus)
47		goto err;
48	platform_set_drvdata(pdev, nvdimm_bus);
49
50	rc = walk_iomem_res_desc(IORES_DESC_PERSISTENT_MEMORY_LEGACY,
51			IORESOURCE_MEM, 0, -1, nvdimm_bus, e820_register_one);
52	if (rc)
53		goto err;
54	return 0;
55err:
56	nvdimm_bus_unregister(nvdimm_bus);
57	dev_err(dev, "failed to register legacy persistent memory ranges\n");
58	return rc;
59}
60
61static struct platform_driver e820_pmem_driver = {
62	.probe = e820_pmem_probe,
63	.remove = e820_pmem_remove,
64	.driver = {
65		.name = "e820_pmem",
66	},
67};
68
69module_platform_driver(e820_pmem_driver);
70
71MODULE_ALIAS("platform:e820_pmem*");
72MODULE_LICENSE("GPL v2");
73MODULE_AUTHOR("Intel Corporation");