tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * AMD K8 NUMA support.
3 * Discover the memory map and associated nodes.
4 *
5 * This version reads it directly from the K8 northbridge.
6 *
7 * Copyright 2002,2003 Andi Kleen, SuSE Labs.
8 */
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>
14#include <asm/io.h>
15#include <linux/pci_ids.h>
16#include <asm/types.h>
17#include <asm/mmzone.h>
18#include <asm/proto.h>
19#include <asm/e820.h>
20#include <asm/pci-direct.h>
21#include <asm/numa.h>
22
23static __init int find_northbridge(void)
24{
25 int num;
26
27 for (num = 0; num < 32; num++) {
28 u32 header;
29
30 header = read_pci_config(0, num, 0, 0x00);
31 if (header != (PCI_VENDOR_ID_AMD | (0x1100<<16)))
32 continue;
33
34 header = read_pci_config(0, num, 1, 0x00);
35 if (header != (PCI_VENDOR_ID_AMD | (0x1101<<16)))
36 continue;
37 return num;
38 }
39
40 return -1;
41}
42
43int __init k8_scan_nodes(unsigned long start, unsigned long end)
44{
45 unsigned long prevbase;
46 struct bootnode nodes[8];
47 int nodeid, i, nb;
48 unsigned char nodeids[8];
49 int found = 0;
50 u32 reg;
51 unsigned numnodes;
52 nodemask_t nodes_parsed;
53 unsigned dualcore = 0;
54
55 nodes_clear(nodes_parsed);
56
57 if (!early_pci_allowed())
58 return -1;
59
60 nb = find_northbridge();
61 if (nb < 0)
62 return nb;
63
64 printk(KERN_INFO "Scanning NUMA topology in Northbridge %d\n", nb);
65
66 reg = read_pci_config(0, nb, 0, 0x60);
67 numnodes = ((reg >> 4) & 0xF) + 1;
68
69 printk(KERN_INFO "Number of nodes %d\n", numnodes);
70
71 memset(&nodes,0,sizeof(nodes));
72 prevbase = 0;
73 for (i = 0; i < 8; i++) {
74 unsigned long base,limit;
75 u32 nodeid;
76
77 /* Undefined before E stepping, but hopefully 0 */
78 dualcore |= ((read_pci_config(0, nb, 3, 0xe8) >> 12) & 3) == 1;
79 base = read_pci_config(0, nb, 1, 0x40 + i*8);
80 limit = read_pci_config(0, nb, 1, 0x44 + i*8);
81
82 nodeid = limit & 7;
83 nodeids[i] = nodeid;
84 if ((base & 3) == 0) {
85 if (i < numnodes)
86 printk("Skipping disabled node %d\n", i);
87 continue;
88 }
89 if (nodeid >= numnodes) {
90 printk("Ignoring excess node %d (%lx:%lx)\n", nodeid,
91 base, limit);
92 continue;
93 }
94
95 if (!limit) {
96 printk(KERN_INFO "Skipping node entry %d (base %lx)\n", i,
97 base);
98 continue;
99 }
100 if ((base >> 8) & 3 || (limit >> 8) & 3) {
101 printk(KERN_ERR "Node %d using interleaving mode %lx/%lx\n",
102 nodeid, (base>>8)&3, (limit>>8) & 3);
103 return -1;
104 }
105 if (node_isset(nodeid, nodes_parsed)) {
106 printk(KERN_INFO "Node %d already present. Skipping\n",
107 nodeid);
108 continue;
109 }
110
111 limit >>= 16;
112 limit <<= 24;
113 limit |= (1<<24)-1;
114 limit++;
115
116 if (limit > end_pfn << PAGE_SHIFT)
117 limit = end_pfn << PAGE_SHIFT;
118 if (limit <= base)
119 continue;
120
121 base >>= 16;
122 base <<= 24;
123
124 if (base < start)
125 base = start;
126 if (limit > end)
127 limit = end;
128 if (limit == base) {
129 printk(KERN_ERR "Empty node %d\n", nodeid);
130 continue;
131 }
132 if (limit < base) {
133 printk(KERN_ERR "Node %d bogus settings %lx-%lx.\n",
134 nodeid, base, limit);
135 continue;
136 }
137
138 /* Could sort here, but pun for now. Should not happen anyroads. */
139 if (prevbase > base) {
140 printk(KERN_ERR "Node map not sorted %lx,%lx\n",
141 prevbase,base);
142 return -1;
143 }
144
145 printk(KERN_INFO "Node %d MemBase %016lx Limit %016lx\n",
146 nodeid, base, limit);
147
148 found++;
149
150 nodes[nodeid].start = base;
151 nodes[nodeid].end = limit;
152 e820_register_active_regions(nodeid,
153 nodes[nodeid].start >> PAGE_SHIFT,
154 nodes[nodeid].end >> PAGE_SHIFT);
155
156 prevbase = base;
157
158 node_set(nodeid, nodes_parsed);
159 }
160
161 if (!found)
162 return -1;
163
164 memnode_shift = compute_hash_shift(nodes, 8);
165 if (memnode_shift < 0) {
166 printk(KERN_ERR "No NUMA node hash function found. Contact maintainer\n");
167 return -1;
168 }
169 printk(KERN_INFO "Using node hash shift of %d\n", memnode_shift);
170
171 for (i = 0; i < 8; i++) {
172 if (nodes[i].start != nodes[i].end) {
173 nodeid = nodeids[i];
174 apicid_to_node[nodeid << dualcore] = i;
175 apicid_to_node[(nodeid << dualcore) + dualcore] = i;
176 setup_node_bootmem(i, nodes[i].start, nodes[i].end);
177 }
178 }
179
180 numa_init_array();
181 return 0;
182}