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 * { X86_VENDOR_INTEL, 6, 0x12 } 20 * or to match a specific CPU feature 21 * { X86_FEATURE_MATCH(X86_FEATURE_FOOBAR) } 22 * 23 * Fields can be wildcarded with %X86_VENDOR_ANY, %X86_FAMILY_ANY, 24 * %X86_MODEL_ANY, %X86_FEATURE_ANY or 0 (except for vendor) 25 * 26 * Arrays used to match for this should also be declared using 27 * MODULE_DEVICE_TABLE(x86cpu, ...) 28 * 29 * This always matches against the boot cpu, assuming models and features are 30 * consistent over all CPUs. 31 */ 32 const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match) 33 { 34 const struct x86_cpu_id *m; 35 struct cpuinfo_x86 *c = &boot_cpu_data; 36 37 for (m = match; m->vendor | m->family | m->model | m->feature; m++) { 38 if (m->vendor != X86_VENDOR_ANY && c->x86_vendor != m->vendor) 39 continue; 40 if (m->family != X86_FAMILY_ANY && c->x86 != m->family) 41 continue; 42 if (m->model != X86_MODEL_ANY && c->x86_model != m->model) 43 continue; 44 if (m->feature != X86_FEATURE_ANY && !cpu_has(c, m->feature)) 45 continue; 46 return m; 47 } 48 return NULL; 49 } 50 EXPORT_SYMBOL(x86_match_cpu); 51 52 static const struct x86_cpu_desc * 53 x86_match_cpu_with_stepping(const struct x86_cpu_desc *match) 54 { 55 struct cpuinfo_x86 *c = &boot_cpu_data; 56 const struct x86_cpu_desc *m; 57 58 for (m = match; m->x86_family | m->x86_model; m++) { 59 if (c->x86_vendor != m->x86_vendor) 60 continue; 61 if (c->x86 != m->x86_family) 62 continue; 63 if (c->x86_model != m->x86_model) 64 continue; 65 if (c->x86_stepping != m->x86_stepping) 66 continue; 67 return m; 68 } 69 return NULL; 70 } 71 72 bool x86_cpu_has_min_microcode_rev(const struct x86_cpu_desc *table) 73 { 74 const struct x86_cpu_desc *res = x86_match_cpu_with_stepping(table); 75 76 if (!res || res->x86_microcode_rev > boot_cpu_data.microcode) 77 return false; 78 79 return true; 80 } 81 EXPORT_SYMBOL_GPL(x86_cpu_has_min_microcode_rev); 82