arch/all-pc/kernel/apic.c

   1 /*
   2     Copyright © 1995-2011, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <exec/memory.h>
   7 #include <proto/exec.h>
   8
   9 #include "kernel_base.h"
  10 #include "kernel_debug.h"
  11 #include "kernel_intern.h"
  12 #include "apic.h"
  13
  14 #define D(x)
  15
  16 /* Initialize APIC by probing */
  17 struct APICData *core_APIC_Probe(void)
  18 {
  19     struct APICData *data;
  20 #ifdef __i386__
  21     /* Only i386 needs detection. On x86-64 APIC is always present. */
  22     ULONG arg = 1;
  23     ULONG res;
  24
  25     asm volatile("cpuid":"+a"(arg),"=d"(res)::"%ebx", "%ecx");
  26
  27     if (!(res & (1 << 9)))
  28         return NULL;
  29
  30     D(bug("[APIC] Detected by CPUID instruction\n"));
  31 #endif
  32
  33     /* Assuming uniprocessor IBM PC compatible */
  34     data = AllocMem(sizeof(struct APICData) + sizeof(struct CPUData), MEMF_CLEAR);
  35     if (!data)
  36         return NULL;
  37
  38     data->lapicBase        = core_APIC_GetBase();
  39     data->count            = 1;
  40     data->flags            = APF_8259;
  41     data->cores[0].lapicID = core_APIC_GetID(data->lapicBase);
  42
  43     /* Just initialize to default state */
  44     core_APIC_Init(data, 0);
  45     return data;
  46 }
  47
  48 UBYTE core_APIC_GetNumber(struct APICData *data)
  49 {
  50     UBYTE __APICLogicalID;
  51     UBYTE __APICNo;
  52
  53     if (!data)
  54     {
  55         /* No APIC data -> uniprocessor system */
  56         return 0;
  57     }
  58
  59     __APICLogicalID = core_APIC_GetID(data->lapicBase);
  60
  61     for (__APICNo = 0; __APICNo < data->count; __APICNo++)
  62     {
  63         if (data->cores[__APICNo].lapicID == __APICLogicalID)
  64             return __APICNo;
  65     }
  66
  67     return -1;
  68 }