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 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 30 static int e820_range_to_nid(resource_size_t addr) 31 { 32 return memory_add_physaddr_to_nid(addr); 33 } 34 #else 35 static int e820_range_to_nid(resource_size_t addr) 36 { 37 return NUMA_NO_NODE; 38 } 39 #endif 40 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 ndr_desc.target_node = ndr_desc.numa_node; 51 set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags); 52 if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc)) 53 return -ENXIO; 54 return 0; 55 } 56 57 static int e820_pmem_probe(struct platform_device *pdev) 58 { 59 static struct nvdimm_bus_descriptor nd_desc; 60 struct device *dev = &pdev->dev; 61 struct nvdimm_bus *nvdimm_bus; 62 int rc = -ENXIO; 63 64 nd_desc.attr_groups = e820_pmem_attribute_groups; 65 nd_desc.provider_name = "e820"; 66 nd_desc.module = THIS_MODULE; 67 nvdimm_bus = nvdimm_bus_register(dev, &nd_desc); 68 if (!nvdimm_bus) 69 goto err; 70 platform_set_drvdata(pdev, nvdimm_bus); 71 72 rc = walk_iomem_res_desc(IORES_DESC_PERSISTENT_MEMORY_LEGACY, 73 IORESOURCE_MEM, 0, -1, nvdimm_bus, e820_register_one); 74 if (rc) 75 goto err; 76 return 0; 77 err: 78 nvdimm_bus_unregister(nvdimm_bus); 79 dev_err(dev, "failed to register legacy persistent memory ranges\n"); 80 return rc; 81 } 82 83 static struct platform_driver e820_pmem_driver = { 84 .probe = e820_pmem_probe, 85 .remove = e820_pmem_remove, 86 .driver = { 87 .name = "e820_pmem", 88 }, 89 }; 90 91 module_platform_driver(e820_pmem_driver); 92 93 MODULE_ALIAS("platform:e820_pmem*"); 94 MODULE_LICENSE("GPL v2"); 95 MODULE_AUTHOR("Intel Corporation"); 96