3 * Discover the memory map and associated nodes.
5 * This version reads it directly from the K8 northbridge.
7 * Copyright 2002,2003 Andi Kleen, SuSE Labs.
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/string.h>
12 #include <linux/module.h>
13 #include <linux/nodemask.h>
15 #include <linux/pci_ids.h>
16 #include <asm/types.h>
17 #include <asm/mmzone.h>
18 #include <asm/proto.h>
20 #include <asm/pci-direct.h>
23 static __init int find_northbridge(void)
27 for (num = 0; num < 32; num++) {
30 header = read_pci_config(0, num, 0, 0x00);
31 if (header != (PCI_VENDOR_ID_AMD | (0x1100<<16)))
34 header = read_pci_config(0, num, 1, 0x00);
35 if (header != (PCI_VENDOR_ID_AMD | (0x1101<<16)))
43 int __init k8_scan_nodes(unsigned long start, unsigned long end)
45 unsigned long prevbase;
46 struct bootnode nodes[8];
48 unsigned char nodeids[8];
56 if (!early_pci_allowed())
59 nb = find_northbridge();
63 printk(KERN_INFO "Scanning NUMA topology in Northbridge %d\n", nb);
65 reg = read_pci_config(0, nb, 0, 0x60);
66 numnodes = ((reg >> 4) & 0xF) + 1;
70 printk(KERN_INFO "Number of nodes %d\n", numnodes);
72 memset(&nodes, 0, sizeof(nodes));
74 for (i = 0; i < 8; i++) {
75 unsigned long base, limit;
78 base = read_pci_config(0, nb, 1, 0x40 + i*8);
79 limit = read_pci_config(0, nb, 1, 0x44 + i*8);
83 if ((base & 3) == 0) {
85 printk("Skipping disabled node %d\n", i);
88 if (nodeid >= numnodes) {
89 printk("Ignoring excess node %d (%lx:%lx)\n", nodeid,
95 printk(KERN_INFO "Skipping node entry %d (base %lx)\n",
99 if ((base >> 8) & 3 || (limit >> 8) & 3) {
100 printk(KERN_ERR "Node %d using interleaving mode %lx/%lx\n",
101 nodeid, (base>>8)&3, (limit>>8) & 3);
104 if (node_isset(nodeid, node_possible_map)) {
105 printk(KERN_INFO "Node %d already present. Skipping\n",
115 if (limit > end_pfn << PAGE_SHIFT)
116 limit = end_pfn << PAGE_SHIFT;
128 printk(KERN_ERR "Empty node %d\n", nodeid);
132 printk(KERN_ERR "Node %d bogus settings %lx-%lx.\n",
133 nodeid, base, limit);
137 /* Could sort here, but pun for now. Should not happen anyroads. */
138 if (prevbase > base) {
139 printk(KERN_ERR "Node map not sorted %lx,%lx\n",
144 printk(KERN_INFO "Node %d MemBase %016lx Limit %016lx\n",
145 nodeid, base, limit);
149 nodes[nodeid].start = base;
150 nodes[nodeid].end = limit;
151 e820_register_active_regions(nodeid,
152 nodes[nodeid].start >> PAGE_SHIFT,
153 nodes[nodeid].end >> PAGE_SHIFT);
157 node_set(nodeid, node_possible_map);
163 memnode_shift = compute_hash_shift(nodes, 8);
164 if (memnode_shift < 0) {
165 printk(KERN_ERR "No NUMA node hash function found. Contact maintainer\n");
168 printk(KERN_INFO "Using node hash shift of %d\n", memnode_shift);
170 /* use the coreid bits from early_identify_cpu */
171 bits = boot_cpu_data.x86_coreid_bits;
174 for (i = 0; i < 8; i++) {
175 if (nodes[i].start != nodes[i].end) {
177 for (j = 0; j < cores; j++)
178 apicid_to_node[(nodeid << bits) + j] = i;
179 setup_node_bootmem(i, nodes[i].start, nodes[i].end);