2 * ACPI 3.0 based NUMA setup
3 * Copyright 2004 Andi Kleen, SuSE Labs.
5 * Reads the ACPI SRAT table to figure out what memory belongs to which CPUs.
7 * Called from acpi_numa_init while reading the SRAT and SLIT tables.
8 * Assumes all memory regions belonging to a single proximity domain
9 * are in one chunk. Holes between them will be included in the node.
12 #include <linux/kernel.h>
13 #include <linux/acpi.h>
14 #include <linux/mmzone.h>
15 #include <linux/bitmap.h>
16 #include <linux/module.h>
17 #include <linux/topology.h>
18 #include <asm/proto.h>
21 static struct acpi_table_slit *acpi_slit;
23 static nodemask_t nodes_parsed __initdata;
24 static nodemask_t nodes_found __initdata;
25 static struct node nodes[MAX_NUMNODES] __initdata;
26 static __u8 pxm2node[256] = { [0 ... 255] = 0xff };
28 static __init int setup_node(int pxm)
30 unsigned node = pxm2node[pxm];
32 if (nodes_weight(nodes_found) >= MAX_NUMNODES)
34 node = first_unset_node(nodes_found);
35 node_set(node, nodes_found);
41 static __init int conflicting_nodes(unsigned long start, unsigned long end)
44 for_each_online_node(i) {
45 struct node *nd = &nodes[i];
46 if (nd->start == nd->end)
48 if (nd->end > start && nd->start < end)
50 if (nd->end == end && nd->start == start)
56 static __init void cutoff_node(int i, unsigned long start, unsigned long end)
58 struct node *nd = &nodes[i];
59 if (nd->start < start) {
61 if (nd->end < nd->start)
68 if (nd->start > nd->end)
73 static __init void bad_srat(void)
75 printk(KERN_ERR "SRAT: SRAT not used.\n");
79 static __init inline int srat_disabled(void)
81 return numa_off || acpi_numa < 0;
84 /* Callback for SLIT parsing */
85 void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
90 /* Callback for Proximity Domain -> LAPIC mapping */
92 acpi_numa_processor_affinity_init(struct acpi_table_processor_affinity *pa)
95 if (srat_disabled() || pa->flags.enabled == 0)
97 pxm = pa->proximity_domain;
98 node = setup_node(pxm);
100 printk(KERN_ERR "SRAT: Too many proximity domains %x\n", pxm);
104 apicid_to_node[pa->apic_id] = node;
106 printk(KERN_INFO "SRAT: PXM %u -> APIC %u -> Node %u\n",
107 pxm, pa->apic_id, node);
110 /* Callback for parsing of the Proximity Domain <-> Memory Area mappings */
112 acpi_numa_memory_affinity_init(struct acpi_table_memory_affinity *ma)
115 unsigned long start, end;
119 if (srat_disabled() || ma->flags.enabled == 0)
121 pxm = ma->proximity_domain;
122 node = setup_node(pxm);
124 printk(KERN_ERR "SRAT: Too many proximity domains.\n");
128 start = ma->base_addr_lo | ((u64)ma->base_addr_hi << 32);
129 end = start + (ma->length_lo | ((u64)ma->length_hi << 32));
130 /* It is fine to add this area to the nodes data it will be used later*/
131 if (ma->flags.hot_pluggable == 1)
132 printk(KERN_INFO "SRAT: hot plug zone found %lx - %lx \n",
134 i = conflicting_nodes(start, end);
137 "SRAT: pxm %d overlap %lx-%lx with node %d(%Lx-%Lx)\n",
138 pxm, start, end, i, nodes[i].start, nodes[i].end);
143 if (!node_test_and_set(node, nodes_parsed)) {
147 if (start < nd->start)
152 if (!(nd->end & 0xfff))
154 printk(KERN_INFO "SRAT: Node %u PXM %u %Lx-%Lx\n", node, pxm,
158 void __init acpi_numa_arch_fixup(void) {}
160 /* Use the information discovered above to actually set up the nodes. */
161 int __init acpi_scan_nodes(unsigned long start, unsigned long end)
166 memnode_shift = compute_hash_shift(nodes, nodes_weight(nodes_parsed));
167 if (memnode_shift < 0) {
169 "SRAT: No NUMA node hash function found. Contact maintainer\n");
173 for (i = 0; i < MAX_NUMNODES; i++) {
174 if (!node_isset(i, nodes_parsed))
176 cutoff_node(i, start, end);
177 if (nodes[i].start == nodes[i].end) {
178 node_clear(i, nodes_parsed);
181 setup_node_bootmem(i, nodes[i].start, nodes[i].end);
183 for (i = 0; i < NR_CPUS; i++) {
184 if (cpu_to_node[i] == NUMA_NO_NODE)
186 if (!node_isset(cpu_to_node[i], nodes_parsed))
187 cpu_to_node[i] = NUMA_NO_NODE;
193 int node_to_pxm(int n)
196 if (pxm2node[n] == n)
198 for (i = 0; i < 256; i++)
199 if (pxm2node[i] == n)
204 int __node_distance(int a, int b)
209 return a == b ? 10 : 20;
210 index = acpi_slit->localities * node_to_pxm(a);
211 return acpi_slit->entry[index + node_to_pxm(b)];
214 EXPORT_SYMBOL(__node_distance);