LXR linux/arch/x86/kernel/cpu/match.c

   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 */
  32const 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}
  50EXPORT_SYMBOL(x86_match_cpu);
  51