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_VFM_FEATURE(INTEL_BROADWELL, X86_FEATURE_ANY, NULL); 21 * 22 * Fields can be wildcarded with %X86_VENDOR_ANY, %X86_FAMILY_ANY, 23 * %X86_MODEL_ANY, %X86_FEATURE_ANY (except for vendor) 24 * 25 * asm/cpu_device_id.h contains a set of useful macros which are shortcuts 26 * for various common selections. The above can be shortened to: 27 * 28 * X86_MATCH_VFM(INTEL_BROADWELL, NULL); 29 * 30 * Arrays used to match for this should also be declared using 31 * MODULE_DEVICE_TABLE(x86cpu, ...) 32 * 33 * This always matches against the boot cpu, assuming models and features are 34 * consistent over all CPUs. 35 */ 36 const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match) 37 { 38 const struct x86_cpu_id *m; 39 struct cpuinfo_x86 *c = &boot_cpu_data; 40 41 for (m = match; m->flags & X86_CPU_ID_FLAG_ENTRY_VALID; m++) { 42 if (m->vendor != X86_VENDOR_ANY && c->x86_vendor != m->vendor) 43 continue; 44 if (m->family != X86_FAMILY_ANY && c->x86 != m->family) 45 continue; 46 if (m->model != X86_MODEL_ANY && c->x86_model != m->model) 47 continue; 48 if (m->steppings != X86_STEPPING_ANY && 49 !(BIT(c->x86_stepping) & m->steppings)) 50 continue; 51 if (m->feature != X86_FEATURE_ANY && !cpu_has(c, m->feature)) 52 continue; 53 return m; 54 } 55 return NULL; 56 } 57 EXPORT_SYMBOL(x86_match_cpu); 58 59 static const struct x86_cpu_desc * 60 x86_match_cpu_with_stepping(const struct x86_cpu_desc *match) 61 { 62 struct cpuinfo_x86 *c = &boot_cpu_data; 63 const struct x86_cpu_desc *m; 64 65 for (m = match; m->x86_family | m->x86_model; m++) { 66 if (c->x86_vendor != m->x86_vendor) 67 continue; 68 if (c->x86 != m->x86_family) 69 continue; 70 if (c->x86_model != m->x86_model) 71 continue; 72 if (c->x86_stepping != m->x86_stepping) 73 continue; 74 return m; 75 } 76 return NULL; 77 } 78 79 bool x86_cpu_has_min_microcode_rev(const struct x86_cpu_desc *table) 80 { 81 const struct x86_cpu_desc *res = x86_match_cpu_with_stepping(table); 82 83 if (!res || res->x86_microcode_rev > boot_cpu_data.microcode) 84 return false; 85 86 return true; 87 } 88 EXPORT_SYMBOL_GPL(x86_cpu_has_min_microcode_rev); 89