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(start: 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(nr: ND_REGION_PAGEMAP, addr: &ndr_desc.flags);
31 if (!nvdimm_pmem_region_create(nvdimm_bus, ndr_desc: &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(parent: dev, nfit_desc: &nd_desc);
46 if (!nvdimm_bus)
47 goto err;
48 platform_set_drvdata(pdev, data: nvdimm_bus);
49
50 rc = walk_iomem_res_desc(desc: IORES_DESC_PERSISTENT_MEMORY_LEGACY,
51 IORESOURCE_MEM, start: 0, end: -1, arg: nvdimm_bus, func: 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");
74

source code of linux/drivers/nvdimm/e820.c