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 11 static const struct attribute_group *e820_pmem_attribute_groups[] = { 12 &nvdimm_bus_attribute_group, 13 NULL, 14 }; 15 16 static const struct attribute_group *e820_pmem_region_attribute_groups[] = { 17 &nd_region_attribute_group, 18 &nd_device_attribute_group, 19 NULL, 20 }; 21 22 static int e820_pmem_remove(struct platform_device *pdev) 23 { 24 struct nvdimm_bus *nvdimm_bus = platform_get_drvdata(pdev); 25 26 nvdimm_bus_unregister(nvdimm_bus); 27 return 0; 28 } 29 30 #ifdef CONFIG_MEMORY_HOTPLUG 31 static int e820_range_to_nid(resource_size_t addr) 32 { 33 return memory_add_physaddr_to_nid(addr); 34 } 35 #else 36 static int e820_range_to_nid(resource_size_t addr) 37 { 38 return NUMA_NO_NODE; 39 } 40 #endif 41 42 static int e820_register_one(struct resource *res, void *data) 43 { 44 struct nd_region_desc ndr_desc; 45 struct nvdimm_bus *nvdimm_bus = data; 46 47 memset(&ndr_desc, 0, sizeof(ndr_desc)); 48 ndr_desc.res = res; 49 ndr_desc.attr_groups = e820_pmem_region_attribute_groups; 50 ndr_desc.numa_node = e820_range_to_nid(res->start); 51 ndr_desc.target_node = ndr_desc.numa_node; 52 set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags); 53 if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc)) 54 return -ENXIO; 55 return 0; 56 } 57 58 static int e820_pmem_probe(struct platform_device *pdev) 59 { 60 static struct nvdimm_bus_descriptor nd_desc; 61 struct device *dev = &pdev->dev; 62 struct nvdimm_bus *nvdimm_bus; 63 int rc = -ENXIO; 64 65 nd_desc.attr_groups = e820_pmem_attribute_groups; 66 nd_desc.provider_name = "e820"; 67 nd_desc.module = THIS_MODULE; 68 nvdimm_bus = nvdimm_bus_register(dev, &nd_desc); 69 if (!nvdimm_bus) 70 goto err; 71 platform_set_drvdata(pdev, nvdimm_bus); 72 73 rc = walk_iomem_res_desc(IORES_DESC_PERSISTENT_MEMORY_LEGACY, 74 IORESOURCE_MEM, 0, -1, nvdimm_bus, e820_register_one); 75 if (rc) 76 goto err; 77 return 0; 78 err: 79 nvdimm_bus_unregister(nvdimm_bus); 80 dev_err(dev, "failed to register legacy persistent memory ranges\n"); 81 return rc; 82 } 83 84 static struct platform_driver e820_pmem_driver = { 85 .probe = e820_pmem_probe, 86 .remove = e820_pmem_remove, 87 .driver = { 88 .name = "e820_pmem", 89 }, 90 }; 91 92 module_platform_driver(e820_pmem_driver); 93 94 MODULE_ALIAS("platform:e820_pmem*"); 95 MODULE_LICENSE("GPL v2"); 96 MODULE_AUTHOR("Intel Corporation"); 97