|
| 1 | +// SPDX-License-Identifier: GPL-2.0 |
| 2 | +/* |
| 3 | + * Copyright (c) 2025, Intel Corporation. |
| 4 | + * |
| 5 | + * Memory Range and Region Mapping (MRRM) structure |
| 6 | + * |
| 7 | + * Parse and report the platform's MRRM table in /sys. |
| 8 | + */ |
| 9 | + |
| 10 | +#define pr_fmt(fmt) "acpi/mrrm: " fmt |
| 11 | + |
| 12 | +#include <linux/acpi.h> |
| 13 | +#include <linux/init.h> |
| 14 | +#include <linux/string.h> |
| 15 | +#include <linux/sysfs.h> |
| 16 | + |
| 17 | +/* Default assume one memory region covering all system memory, per the spec */ |
| 18 | +static int max_mem_region = 1; |
| 19 | + |
| 20 | +/* Access for use by resctrl file system */ |
| 21 | +int acpi_mrrm_max_mem_region(void) |
| 22 | +{ |
| 23 | + return max_mem_region; |
| 24 | +} |
| 25 | + |
| 26 | +struct mrrm_mem_range_entry { |
| 27 | + u64 base; |
| 28 | + u64 length; |
| 29 | + int node; |
| 30 | + u8 local_region_id; |
| 31 | + u8 remote_region_id; |
| 32 | +}; |
| 33 | + |
| 34 | +static struct mrrm_mem_range_entry *mrrm_mem_range_entry; |
| 35 | +static u32 mrrm_mem_entry_num; |
| 36 | + |
| 37 | +static int get_node_num(struct mrrm_mem_range_entry *e) |
| 38 | +{ |
| 39 | + unsigned int nid; |
| 40 | + |
| 41 | + for_each_online_node(nid) { |
| 42 | + for (int z = 0; z < MAX_NR_ZONES; z++) { |
| 43 | + struct zone *zone = NODE_DATA(nid)->node_zones + z; |
| 44 | + |
| 45 | + if (!populated_zone(zone)) |
| 46 | + continue; |
| 47 | + if (zone_intersects(zone, PHYS_PFN(e->base), PHYS_PFN(e->length))) |
| 48 | + return zone_to_nid(zone); |
| 49 | + } |
| 50 | + } |
| 51 | + |
| 52 | + return -ENOENT; |
| 53 | +} |
| 54 | + |
| 55 | +static __init int acpi_parse_mrrm(struct acpi_table_header *table) |
| 56 | +{ |
| 57 | + struct acpi_mrrm_mem_range_entry *mre_entry; |
| 58 | + struct acpi_table_mrrm *mrrm; |
| 59 | + void *mre, *mrrm_end; |
| 60 | + int mre_count = 0; |
| 61 | + |
| 62 | + mrrm = (struct acpi_table_mrrm *)table; |
| 63 | + if (!mrrm) |
| 64 | + return -ENODEV; |
| 65 | + |
| 66 | + if (mrrm->flags & ACPI_MRRM_FLAGS_REGION_ASSIGNMENT_OS) |
| 67 | + return -EOPNOTSUPP; |
| 68 | + |
| 69 | + mrrm_end = (void *)mrrm + mrrm->header.length - 1; |
| 70 | + mre = (void *)mrrm + sizeof(struct acpi_table_mrrm); |
| 71 | + while (mre < mrrm_end) { |
| 72 | + mre_entry = mre; |
| 73 | + mre_count++; |
| 74 | + mre += mre_entry->header.length; |
| 75 | + } |
| 76 | + if (!mre_count) { |
| 77 | + pr_info(FW_BUG "No ranges listed in MRRM table\n"); |
| 78 | + return -EINVAL; |
| 79 | + } |
| 80 | + |
| 81 | + mrrm_mem_range_entry = kmalloc_array(mre_count, sizeof(*mrrm_mem_range_entry), |
| 82 | + GFP_KERNEL | __GFP_ZERO); |
| 83 | + if (!mrrm_mem_range_entry) |
| 84 | + return -ENOMEM; |
| 85 | + |
| 86 | + mre = (void *)mrrm + sizeof(struct acpi_table_mrrm); |
| 87 | + while (mre < mrrm_end) { |
| 88 | + struct mrrm_mem_range_entry *e; |
| 89 | + |
| 90 | + mre_entry = mre; |
| 91 | + e = mrrm_mem_range_entry + mrrm_mem_entry_num; |
| 92 | + |
| 93 | + e->base = mre_entry->addr_base; |
| 94 | + e->length = mre_entry->addr_len; |
| 95 | + e->node = get_node_num(e); |
| 96 | + |
| 97 | + if (mre_entry->region_id_flags & ACPI_MRRM_VALID_REGION_ID_FLAGS_LOCAL) |
| 98 | + e->local_region_id = mre_entry->local_region_id; |
| 99 | + else |
| 100 | + e->local_region_id = -1; |
| 101 | + if (mre_entry->region_id_flags & ACPI_MRRM_VALID_REGION_ID_FLAGS_REMOTE) |
| 102 | + e->remote_region_id = mre_entry->remote_region_id; |
| 103 | + else |
| 104 | + e->remote_region_id = -1; |
| 105 | + |
| 106 | + mrrm_mem_entry_num++; |
| 107 | + mre += mre_entry->header.length; |
| 108 | + } |
| 109 | + |
| 110 | + max_mem_region = mrrm->max_mem_region; |
| 111 | + |
| 112 | + return 0; |
| 113 | +} |
| 114 | + |
| 115 | +#define RANGE_ATTR(name, fmt) \ |
| 116 | +static ssize_t name##_show(struct kobject *kobj, \ |
| 117 | + struct kobj_attribute *attr, char *buf) \ |
| 118 | +{ \ |
| 119 | + struct mrrm_mem_range_entry *mre; \ |
| 120 | + const char *kname = kobject_name(kobj); \ |
| 121 | + int n, ret; \ |
| 122 | + \ |
| 123 | + ret = kstrtoint(kname + 5, 10, &n); \ |
| 124 | + if (ret) \ |
| 125 | + return ret; \ |
| 126 | + \ |
| 127 | + mre = mrrm_mem_range_entry + n; \ |
| 128 | + \ |
| 129 | + return sysfs_emit(buf, fmt, mre->name); \ |
| 130 | +} \ |
| 131 | +static struct kobj_attribute name##_attr = __ATTR_RO(name) |
| 132 | + |
| 133 | +RANGE_ATTR(base, "0x%llx\n"); |
| 134 | +RANGE_ATTR(length, "0x%llx\n"); |
| 135 | +RANGE_ATTR(node, "%d\n"); |
| 136 | +RANGE_ATTR(local_region_id, "%d\n"); |
| 137 | +RANGE_ATTR(remote_region_id, "%d\n"); |
| 138 | + |
| 139 | +static struct attribute *memory_range_attrs[] = { |
| 140 | + &base_attr.attr, |
| 141 | + &length_attr.attr, |
| 142 | + &node_attr.attr, |
| 143 | + &local_region_id_attr.attr, |
| 144 | + &remote_region_id_attr.attr, |
| 145 | + NULL |
| 146 | +}; |
| 147 | + |
| 148 | +ATTRIBUTE_GROUPS(memory_range); |
| 149 | + |
| 150 | +static __init int add_boot_memory_ranges(void) |
| 151 | +{ |
| 152 | + struct kobject *pkobj, *kobj; |
| 153 | + int ret = -EINVAL; |
| 154 | + char *name; |
| 155 | + |
| 156 | + pkobj = kobject_create_and_add("memory_ranges", acpi_kobj); |
| 157 | + |
| 158 | + for (int i = 0; i < mrrm_mem_entry_num; i++) { |
| 159 | + name = kasprintf(GFP_KERNEL, "range%d", i); |
| 160 | + if (!name) { |
| 161 | + ret = -ENOMEM; |
| 162 | + break; |
| 163 | + } |
| 164 | + |
| 165 | + kobj = kobject_create_and_add(name, pkobj); |
| 166 | + |
| 167 | + ret = sysfs_create_groups(kobj, memory_range_groups); |
| 168 | + if (ret) |
| 169 | + return ret; |
| 170 | + } |
| 171 | + |
| 172 | + return ret; |
| 173 | +} |
| 174 | + |
| 175 | +static __init int mrrm_init(void) |
| 176 | +{ |
| 177 | + int ret; |
| 178 | + |
| 179 | + ret = acpi_table_parse(ACPI_SIG_MRRM, acpi_parse_mrrm); |
| 180 | + if (ret < 0) |
| 181 | + return ret; |
| 182 | + |
| 183 | + return add_boot_memory_ranges(); |
| 184 | +} |
| 185 | +device_initcall(mrrm_init); |
0 commit comments