1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <asm/cpu_device_id.h> |
3 | #include <asm/cpufeature.h> |
4 | #include <linux/cpu.h> |
5 | #include <linux/export.h> |
6 | #include <linux/slab.h> |
7 | |
8 | /** |
9 | * x86_match_cpu - match current CPU again an array of x86_cpu_ids |
10 | * @match: Pointer to array of x86_cpu_ids. Last entry terminated with |
11 | * {}. |
12 | * |
13 | * Return the entry if the current CPU matches the entries in the |
14 | * passed x86_cpu_id match table. Otherwise NULL. The match table |
15 | * contains vendor (X86_VENDOR_*), family, model and feature bits or |
16 | * respective wildcard entries. |
17 | * |
18 | * A typical table entry would be to match a specific CPU |
19 | * |
20 | * X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, INTEL_FAM6_BROADWELL, |
21 | * X86_FEATURE_ANY, NULL); |
22 | * |
23 | * Fields can be wildcarded with %X86_VENDOR_ANY, %X86_FAMILY_ANY, |
24 | * %X86_MODEL_ANY, %X86_FEATURE_ANY (except for vendor) |
25 | * |
26 | * asm/cpu_device_id.h contains a set of useful macros which are shortcuts |
27 | * for various common selections. The above can be shortened to: |
28 | * |
29 | * X86_MATCH_INTEL_FAM6_MODEL(BROADWELL, NULL); |
30 | * |
31 | * Arrays used to match for this should also be declared using |
32 | * MODULE_DEVICE_TABLE(x86cpu, ...) |
33 | * |
34 | * This always matches against the boot cpu, assuming models and features are |
35 | * consistent over all CPUs. |
36 | */ |
37 | const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match) |
38 | { |
39 | const struct x86_cpu_id *m; |
40 | struct cpuinfo_x86 *c = &boot_cpu_data; |
41 | |
42 | for (m = match; |
43 | m->vendor | m->family | m->model | m->steppings | m->feature; |
44 | m++) { |
45 | if (m->vendor != X86_VENDOR_ANY && c->x86_vendor != m->vendor) |
46 | continue; |
47 | if (m->family != X86_FAMILY_ANY && c->x86 != m->family) |
48 | continue; |
49 | if (m->model != X86_MODEL_ANY && c->x86_model != m->model) |
50 | continue; |
51 | if (m->steppings != X86_STEPPING_ANY && |
52 | !(BIT(c->x86_stepping) & m->steppings)) |
53 | continue; |
54 | if (m->feature != X86_FEATURE_ANY && !cpu_has(c, m->feature)) |
55 | continue; |
56 | return m; |
57 | } |
58 | return NULL; |
59 | } |
60 | EXPORT_SYMBOL(x86_match_cpu); |
61 | |
62 | static const struct x86_cpu_desc * |
63 | x86_match_cpu_with_stepping(const struct x86_cpu_desc *match) |
64 | { |
65 | struct cpuinfo_x86 *c = &boot_cpu_data; |
66 | const struct x86_cpu_desc *m; |
67 | |
68 | for (m = match; m->x86_family | m->x86_model; m++) { |
69 | if (c->x86_vendor != m->x86_vendor) |
70 | continue; |
71 | if (c->x86 != m->x86_family) |
72 | continue; |
73 | if (c->x86_model != m->x86_model) |
74 | continue; |
75 | if (c->x86_stepping != m->x86_stepping) |
76 | continue; |
77 | return m; |
78 | } |
79 | return NULL; |
80 | } |
81 | |
82 | bool x86_cpu_has_min_microcode_rev(const struct x86_cpu_desc *table) |
83 | { |
84 | const struct x86_cpu_desc *res = x86_match_cpu_with_stepping(match: table); |
85 | |
86 | if (!res || res->x86_microcode_rev > boot_cpu_data.microcode) |
87 | return false; |
88 | |
89 | return true; |
90 | } |
91 | EXPORT_SYMBOL_GPL(x86_cpu_has_min_microcode_rev); |
92 | |