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
e820_pmem_remove(struct platform_device * pdev)12 static void 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 }
18
e820_register_one(struct resource * res,void * data)19 static int e820_register_one(struct resource *res, void *data)
20 {
21 struct nd_region_desc ndr_desc;
22 struct nvdimm_bus *nvdimm_bus = data;
23 int nid = phys_to_target_node(res->start);
24
25 memset(&ndr_desc, 0, sizeof(ndr_desc));
26 ndr_desc.res = res;
27 ndr_desc.numa_node = numa_map_to_online_node(nid);
28 ndr_desc.target_node = nid;
29 set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
30 if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc))
31 return -ENXIO;
32 return 0;
33 }
34
e820_pmem_probe(struct platform_device * pdev)35 static int e820_pmem_probe(struct platform_device *pdev)
36 {
37 static struct nvdimm_bus_descriptor nd_desc;
38 struct device *dev = &pdev->dev;
39 struct nvdimm_bus *nvdimm_bus;
40 int rc = -ENXIO;
41
42 nd_desc.provider_name = "e820";
43 nd_desc.module = THIS_MODULE;
44 nvdimm_bus = nvdimm_bus_register(dev, &nd_desc);
45 if (!nvdimm_bus)
46 goto err;
47 platform_set_drvdata(pdev, nvdimm_bus);
48
49 rc = walk_iomem_res_desc(IORES_DESC_PERSISTENT_MEMORY_LEGACY,
50 IORESOURCE_MEM, 0, -1, nvdimm_bus, e820_register_one);
51 if (rc)
52 goto err;
53 return 0;
54 err:
55 nvdimm_bus_unregister(nvdimm_bus);
56 dev_err(dev, "failed to register legacy persistent memory ranges\n");
57 return rc;
58 }
59
60 static struct platform_driver e820_pmem_driver = {
61 .probe = e820_pmem_probe,
62 .remove = e820_pmem_remove,
63 .driver = {
64 .name = "e820_pmem",
65 },
66 };
67
68 module_platform_driver(e820_pmem_driver);
69
70 MODULE_ALIAS("platform:e820_pmem*");
71 MODULE_DESCRIPTION("NVDIMM support for e820 type-12 memory");
72 MODULE_LICENSE("GPL v2");
73 MODULE_AUTHOR("Intel Corporation");
74