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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Check for extended topology enumeration cpuid leaf 0xb and if it
4 * exists, use it for populating initial_apicid and cpu topology
5 * detection.
6 */
7
8#include <linux/cpu.h>
9#include <asm/apic.h>
10#include <asm/pat.h>
11#include <asm/processor.h>
12
13#include "cpu.h"
14
15/* leaf 0xb SMT level */
16#define SMT_LEVEL 0
17
18/* extended topology sub-leaf types */
19#define INVALID_TYPE 0
20#define SMT_TYPE 1
21#define CORE_TYPE 2
22#define DIE_TYPE 5
23
24#define LEAFB_SUBTYPE(ecx) (((ecx) >> 8) & 0xff)
25#define BITS_SHIFT_NEXT_LEVEL(eax) ((eax) & 0x1f)
26#define LEVEL_MAX_SIBLINGS(ebx) ((ebx) & 0xffff)
27
28#ifdef CONFIG_SMP
29unsigned int __max_die_per_package __read_mostly = 1;
30EXPORT_SYMBOL(__max_die_per_package);
31
32/*
33 * Check if given CPUID extended toplogy "leaf" is implemented
34 */
35static int check_extended_topology_leaf(int leaf)
36{
37 unsigned int eax, ebx, ecx, edx;
38
39 cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
40
41 if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE))
42 return -1;
43
44 return 0;
45}
46/*
47 * Return best CPUID Extended Toplogy Leaf supported
48 */
49static int detect_extended_topology_leaf(struct cpuinfo_x86 *c)
50{
51 if (c->cpuid_level >= 0x1f) {
52 if (check_extended_topology_leaf(0x1f) == 0)
53 return 0x1f;
54 }
55
56 if (c->cpuid_level >= 0xb) {
57 if (check_extended_topology_leaf(0xb) == 0)
58 return 0xb;
59 }
60
61 return -1;
62}
63#endif
64
65int detect_extended_topology_early(struct cpuinfo_x86 *c)
66{
67#ifdef CONFIG_SMP
68 unsigned int eax, ebx, ecx, edx;
69 int leaf;
70
71 leaf = detect_extended_topology_leaf(c);
72 if (leaf < 0)
73 return -1;
74
75 set_cpu_cap(c, X86_FEATURE_XTOPOLOGY);
76
77 cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
78 /*
79 * initial apic id, which also represents 32-bit extended x2apic id.
80 */
81 c->initial_apicid = edx;
82 smp_num_siblings = LEVEL_MAX_SIBLINGS(ebx);
83#endif
84 return 0;
85}
86
87/*
88 * Check for extended topology enumeration cpuid leaf, and if it
89 * exists, use it for populating initial_apicid and cpu topology
90 * detection.
91 */
92int detect_extended_topology(struct cpuinfo_x86 *c)
93{
94#ifdef CONFIG_SMP
95 unsigned int eax, ebx, ecx, edx, sub_index;
96 unsigned int ht_mask_width, core_plus_mask_width, die_plus_mask_width;
97 unsigned int core_select_mask, core_level_siblings;
98 unsigned int die_select_mask, die_level_siblings;
99 int leaf;
100
101 leaf = detect_extended_topology_leaf(c);
102 if (leaf < 0)
103 return -1;
104
105 /*
106 * Populate HT related information from sub-leaf level 0.
107 */
108 cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
109 c->initial_apicid = edx;
110 core_level_siblings = smp_num_siblings = LEVEL_MAX_SIBLINGS(ebx);
111 core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
112 die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
113 die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
114
115 sub_index = 1;
116 do {
117 cpuid_count(leaf, sub_index, &eax, &ebx, &ecx, &edx);
118
119 /*
120 * Check for the Core type in the implemented sub leaves.
121 */
122 if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) {
123 core_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
124 core_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
125 die_level_siblings = core_level_siblings;
126 die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
127 }
128 if (LEAFB_SUBTYPE(ecx) == DIE_TYPE) {
129 die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
130 die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
131 }
132
133 sub_index++;
134 } while (LEAFB_SUBTYPE(ecx) != INVALID_TYPE);
135
136 core_select_mask = (~(-1 << core_plus_mask_width)) >> ht_mask_width;
137 die_select_mask = (~(-1 << die_plus_mask_width)) >>
138 core_plus_mask_width;
139
140 c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid,
141 ht_mask_width) & core_select_mask;
142 c->cpu_die_id = apic->phys_pkg_id(c->initial_apicid,
143 core_plus_mask_width) & die_select_mask;
144 c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid,
145 die_plus_mask_width);
146 /*
147 * Reinit the apicid, now that we have extended initial_apicid.
148 */
149 c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
150
151 c->x86_max_cores = (core_level_siblings / smp_num_siblings);
152 __max_die_per_package = (die_level_siblings / core_level_siblings);
153#endif
154 return 0;
155}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Check for extended topology enumeration cpuid leaf 0xb and if it
4 * exists, use it for populating initial_apicid and cpu topology
5 * detection.
6 */
7
8#include <linux/cpu.h>
9#include <asm/apic.h>
10#include <asm/pat.h>
11#include <asm/processor.h>
12
13/* leaf 0xb SMT level */
14#define SMT_LEVEL 0
15
16/* leaf 0xb sub-leaf types */
17#define INVALID_TYPE 0
18#define SMT_TYPE 1
19#define CORE_TYPE 2
20
21#define LEAFB_SUBTYPE(ecx) (((ecx) >> 8) & 0xff)
22#define BITS_SHIFT_NEXT_LEVEL(eax) ((eax) & 0x1f)
23#define LEVEL_MAX_SIBLINGS(ebx) ((ebx) & 0xffff)
24
25/*
26 * Check for extended topology enumeration cpuid leaf 0xb and if it
27 * exists, use it for populating initial_apicid and cpu topology
28 * detection.
29 */
30void detect_extended_topology(struct cpuinfo_x86 *c)
31{
32#ifdef CONFIG_SMP
33 unsigned int eax, ebx, ecx, edx, sub_index;
34 unsigned int ht_mask_width, core_plus_mask_width;
35 unsigned int core_select_mask, core_level_siblings;
36 static bool printed;
37
38 if (c->cpuid_level < 0xb)
39 return;
40
41 cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
42
43 /*
44 * check if the cpuid leaf 0xb is actually implemented.
45 */
46 if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE))
47 return;
48
49 set_cpu_cap(c, X86_FEATURE_XTOPOLOGY);
50
51 /*
52 * initial apic id, which also represents 32-bit extended x2apic id.
53 */
54 c->initial_apicid = edx;
55
56 /*
57 * Populate HT related information from sub-leaf level 0.
58 */
59 core_level_siblings = smp_num_siblings = LEVEL_MAX_SIBLINGS(ebx);
60 core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
61
62 sub_index = 1;
63 do {
64 cpuid_count(0xb, sub_index, &eax, &ebx, &ecx, &edx);
65
66 /*
67 * Check for the Core type in the implemented sub leaves.
68 */
69 if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) {
70 core_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
71 core_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
72 break;
73 }
74
75 sub_index++;
76 } while (LEAFB_SUBTYPE(ecx) != INVALID_TYPE);
77
78 core_select_mask = (~(-1 << core_plus_mask_width)) >> ht_mask_width;
79
80 c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, ht_mask_width)
81 & core_select_mask;
82 c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, core_plus_mask_width);
83 /*
84 * Reinit the apicid, now that we have extended initial_apicid.
85 */
86 c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
87
88 c->x86_max_cores = (core_level_siblings / smp_num_siblings);
89
90 if (!printed) {
91 pr_info("CPU: Physical Processor ID: %d\n",
92 c->phys_proc_id);
93 if (c->x86_max_cores > 1)
94 pr_info("CPU: Processor Core ID: %d\n",
95 c->cpu_core_id);
96 printed = 1;
97 }
98 return;
99#endif
100}