| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame] | 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(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); |