arch/x86/kernel/cpu/nexgen.c

   1 #include <linux/kernel.h>
   2 #include <linux/init.h>
   3 #include <linux/string.h>
   4 #include <asm/processor.h>
   5
   6 #include "cpu.h"
   7
   8 /*
   9  *      Detect a NexGen CPU running without BIOS hypercode new enough
  10  *      to have CPUID. (Thanks to Herbert Oppmann)
  11  */
  12
  13 static int __cpuinit deep_magic_nexgen_probe(void)
  14 {
  15         int ret;
  16
  17         __asm__ __volatile__ (
  18                 "       movw    $0x5555, %%ax\n"
  19                 "       xorw    %%dx,%%dx\n"
  20                 "       movw    $2, %%cx\n"
  21                 "       divw    %%cx\n"
  22                 "       movl    $0, %%eax\n"
  23                 "       jnz     1f\n"
  24                 "       movl    $1, %%eax\n"
  25                 "1:\n"
  26                 : "=a" (ret) : : "cx", "dx" );
  27         return  ret;
  28 }
  29
  30 static void __cpuinit init_nexgen(struct cpuinfo_x86 * c)
  31 {
  32         c->x86_cache_size = 256; /* A few had 1 MB... */
  33 }
  34
  35 static void __cpuinit nexgen_identify(struct cpuinfo_x86 * c)
  36 {
  37         /* Detect NexGen with old hypercode */
  38         if ( deep_magic_nexgen_probe() ) {
  39                 strcpy(c->x86_vendor_id, "NexGenDriven");
  40         }
  41 }
  42
  43 static struct cpu_dev nexgen_cpu_dev __cpuinitdata = {
  44         .c_vendor       = "Nexgen",
  45         .c_ident        = { "NexGenDriven" },
  46         .c_models = {
  47                         { .vendor = X86_VENDOR_NEXGEN,
  48                           .family = 5,
  49                           .model_names = { [1] = "Nx586" }
  50                         },
  51         },
  52         .c_init         = init_nexgen,
  53         .c_identify     = nexgen_identify,
  54 };
  55
  56 int __init nexgen_init_cpu(void)
  57 {
  58         cpu_devs[X86_VENDOR_NEXGEN] = &nexgen_cpu_dev;
  59         return 0;
  60 }