1 /*
2 * Copyright (c) 2015, Christoph Hellwig.
3 * Copyright (c) 2015, Intel Corporation.
4 */
5 #include <linux/platform_device.h>
6 #include <linux/memory_hotplug.h>
7 #include <linux/libnvdimm.h>
8 #include <linux/module.h>
9
10 static const struct attribute_group *e820_pmem_attribute_groups[] = {
11 &nvdimm_bus_attribute_group,
12 NULL,
13 };
14
15 static const struct attribute_group *e820_pmem_region_attribute_groups[] = {
16 &nd_region_attribute_group,
17 &nd_device_attribute_group,
18 NULL,
19 };
20
e820_pmem_remove(struct platform_device * pdev)21 static int e820_pmem_remove(struct platform_device *pdev)
22 {
23 struct nvdimm_bus *nvdimm_bus = platform_get_drvdata(pdev);
24
25 nvdimm_bus_unregister(nvdimm_bus);
26 return 0;
27 }
28
29 #ifdef CONFIG_MEMORY_HOTPLUG
e820_range_to_nid(resource_size_t addr)30 static int e820_range_to_nid(resource_size_t addr)
31 {
32 return memory_add_physaddr_to_nid(addr);
33 }
34 #else
e820_range_to_nid(resource_size_t addr)35 static int e820_range_to_nid(resource_size_t addr)
36 {
37 return NUMA_NO_NODE;
38 }
39 #endif
40
e820_register_one(struct resource * res,void * data)41 static int e820_register_one(struct resource *res, void *data)
42 {
43 struct nd_region_desc ndr_desc;
44 struct nvdimm_bus *nvdimm_bus = data;
45
46 memset(&ndr_desc, 0, sizeof(ndr_desc));
47 ndr_desc.res = res;
48 ndr_desc.attr_groups = e820_pmem_region_attribute_groups;
49 ndr_desc.numa_node = e820_range_to_nid(res->start);
50 set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
51 if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc))
52 return -ENXIO;
53 return 0;
54 }
55
e820_pmem_probe(struct platform_device * pdev)56 static int e820_pmem_probe(struct platform_device *pdev)
57 {
58 static struct nvdimm_bus_descriptor nd_desc;
59 struct device *dev = &pdev->dev;
60 struct nvdimm_bus *nvdimm_bus;
61 int rc = -ENXIO;
62
63 nd_desc.attr_groups = e820_pmem_attribute_groups;
64 nd_desc.provider_name = "e820";
65 nd_desc.module = THIS_MODULE;
66 nvdimm_bus = nvdimm_bus_register(dev, &nd_desc);
67 if (!nvdimm_bus)
68 goto err;
69 platform_set_drvdata(pdev, nvdimm_bus);
70
71 rc = walk_iomem_res_desc(IORES_DESC_PERSISTENT_MEMORY_LEGACY,
72 IORESOURCE_MEM, 0, -1, nvdimm_bus, e820_register_one);
73 if (rc)
74 goto err;
75 return 0;
76 err:
77 nvdimm_bus_unregister(nvdimm_bus);
78 dev_err(dev, "failed to register legacy persistent memory ranges\n");
79 return rc;
80 }
81
82 static struct platform_driver e820_pmem_driver = {
83 .probe = e820_pmem_probe,
84 .remove = e820_pmem_remove,
85 .driver = {
86 .name = "e820_pmem",
87 },
88 };
89
90 module_platform_driver(e820_pmem_driver);
91
92 MODULE_ALIAS("platform:e820_pmem*");
93 MODULE_LICENSE("GPL v2");
94 MODULE_AUTHOR("Intel Corporation");
95
