aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/mm/amdtopology.c
blob: 048c761d97b09539830ad461a12fc1cb3b7f7674 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
// SPDX-License-Identifier: GPL-2.0
/*
 * AMD NUMA support.
 * Discover the memory map and associated nodes.
 *
 * This version reads it directly from the AMD northbridge.
 *
 * Copyright 2002,2003 Andi Kleen, SuSE Labs.
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/nodemask.h>
#include <linux/memblock.h>
#include <linux/bootmem.h>

#include <asm/io.h>
#include <linux/pci_ids.h>
#include <linux/acpi.h>
#include <asm/types.h>
#include <asm/mmzone.h>
#include <asm/proto.h>
#include <asm/e820/api.h>
#include <asm/pci-direct.h>
#include <asm/numa.h>
#include <asm/mpspec.h>
#include <asm/apic.h>
#include <asm/amd_nb.h>

static unsigned char __initdata nodeids[8];

static __init int find_northbridge(void)
{
	int num;

	for (num = 0; num < 32; num++) {
		u32 header;

		header = read_pci_config(0, num, 0, 0x00);
		if (header != (PCI_VENDOR_ID_AMD | (0x1100<<16)) &&
			header != (PCI_VENDOR_ID_AMD | (0x1200<<16)) &&
			header != (PCI_VENDOR_ID_AMD | (0x1300<<16)))
			continue;

		header = read_pci_config(0, num, 1, 0x00);
		if (header != (PCI_VENDOR_ID_AMD | (0x1101<<16)) &&
			header != (PCI_VENDOR_ID_AMD | (0x1201<<16)) &&
			header != (PCI_VENDOR_ID_AMD | (0x1301<<16)))
			continue;
		return num;
	}

	return -ENOENT;
}

int __init amd_numa_init(void)
{
	u64 start = PFN_PHYS(0);
	u64 end = PFN_PHYS(max_pfn);
	unsigned numnodes;
	u64 prevbase;
	int i, j, nb;
	u32 nodeid, reg;
	unsigned int bits, cores, apicid_base;

	if (!early_pci_allowed())
		return -EINVAL;

	nb = find_northbridge();
	if (nb < 0)
		return nb;

	pr_info("Scanning NUMA topology in Northbridge %d\n", nb);

	reg = read_pci_config(0, nb, 0, 0x60);
	numnodes = ((reg >> 4) & 0xF) + 1;
	if (numnodes <= 1)
		return -ENOENT;

	pr_info("Number of physical nodes %d\n", numnodes);

	prevbase = 0;
	for (i = 0; i < 8; i++) {
		u64 base, limit;

		base = read_pci_config(0, nb, 1, 0x40 + i*8);
		limit = read_pci_config(0, nb, 1, 0x44 + i*8);

		nodeids[i] = nodeid = limit & 7;
		if ((base & 3) == 0) {
			if (i < numnodes)
				pr_info("Skipping disabled node %d\n", i);
			continue;
		}
		if (nodeid >= numnodes) {
			pr_info("Ignoring excess node %d (%Lx:%Lx)\n", nodeid,
				base, limit);
			continue;
		}

		if (!limit) {
			pr_info("Skipping node entry %d (base %Lx)\n",
				i, base);
			continue;
		}
		if ((base >> 8) & 3 || (limit >> 8) & 3) {
			pr_err("Node %d using interleaving mode %Lx/%Lx\n",
			       nodeid, (base >> 8) & 3, (limit >> 8) & 3);
			return -EINVAL;
		}
		if (node_isset(nodeid, numa_nodes_parsed)) {
			pr_info("Node %d already present, skipping\n",
				nodeid);
			continue;
		}

		limit >>= 16;
		limit++;
		limit <<= 24;

		if (limit > end)
			limit = end;
		if (limit <= base)
			continue;

		base >>= 16;
		base <<= 24;

		if (base < start)
			base = start;
		if (limit > end)
			limit = end;
		if (limit == base) {
			pr_err("Empty node %d\n", nodeid);
			continue;
		}
		if (limit < base) {
			pr_err("Node %d bogus settings %Lx-%Lx.\n",
			       nodeid, base, limit);
			continue;
		}

		/* Could sort here, but pun for now. Should not happen anyroads. */
		if (prevbase > base) {
			pr_err("Node map not sorted %Lx,%Lx\n",
			       prevbase, base);
			return -EINVAL;
		}

		pr_info("Node %d MemBase %016Lx Limit %016Lx\n",
			nodeid, base, limit);

		prevbase = base;
		numa_add_memblk(nodeid, base, limit);
		node_set(nodeid, numa_nodes_parsed);
	}

	if (!nodes_weight(numa_nodes_parsed))
		return -ENOENT;

	/*
	 * We seem to have valid NUMA configuration.  Map apicids to nodes
	 * using the coreid bits from early_identify_cpu.
	 */
	bits = boot_cpu_data.x86_coreid_bits;
	cores = 1 << bits;
	apicid_base = 0;

	/*
	 * get boot-time SMP configuration:
	 */
	early_get_smp_config();

	if (boot_cpu_physical_apicid > 0) {
		pr_info("BSP APIC ID: %02x\n", boot_cpu_physical_apicid);
		apicid_base = boot_cpu_physical_apicid;
	}

	for_each_node_mask(i, numa_nodes_parsed)
		for (j = apicid_base; j < cores + apicid_base; j++)
			set_apicid_to_node((i << bits) + j, i);

	return 0;
}