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; m->vendor | m->family | m->model | m->feature; m++) { 43 if (m->vendor != X86_VENDOR_ANY && c->x86_vendor != m->vendor) 44 continue; 45 if (m->family != X86_FAMILY_ANY && c->x86 != m->family) 46 continue; 47 if (m->model != X86_MODEL_ANY && c->x86_model != m->model) 48 continue; 49 if (m->feature != X86_FEATURE_ANY && !cpu_has(c, m->feature)) 50 continue; 51 return m; 52 } 53 return NULL; 54 } 55 EXPORT_SYMBOL(x86_match_cpu); 56 57 static const struct x86_cpu_desc * 58 x86_match_cpu_with_stepping(const struct x86_cpu_desc *match) 59 { 60 struct cpuinfo_x86 *c = &boot_cpu_data; 61 const struct x86_cpu_desc *m; 62 63 for (m = match; m->x86_family | m->x86_model; m++) { 64 if (c->x86_vendor != m->x86_vendor) 65 continue; 66 if (c->x86 != m->x86_family) 67 continue; 68 if (c->x86_model != m->x86_model) 69 continue; 70 if (c->x86_stepping != m->x86_stepping) 71 continue; 72 return m; 73 } 74 return NULL; 75 } 76 77 bool x86_cpu_has_min_microcode_rev(const struct x86_cpu_desc *table) 78 { 79 const struct x86_cpu_desc *res = x86_match_cpu_with_stepping(table); 80 81 if (!res || res->x86_microcode_rev > boot_cpu_data.microcode) 82 return false; 83 84 return true; 85 } 86 EXPORT_SYMBOL_GPL(x86_cpu_has_min_microcode_rev); 87