arch/x86/kernel/acpi/processor.c

   1 /*
   2  * arch/i386/kernel/acpi/processor.c
   3  *
   4  * Copyright (C) 2005 Intel Corporation
   5  *      Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
   6  *      - Added _PDC for platforms with Intel CPUs
   7  */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/acpi.h>
  13
  14 #include <acpi/processor.h>
  15 #include <asm/acpi.h>
  16
  17 static void init_intel_pdc(struct acpi_processor *pr, struct cpuinfo_x86 *c)
  18 {
  19         struct acpi_object_list *obj_list;
  20         union acpi_object *obj;
  21         u32 *buf;
  22
  23         /* allocate and initialize pdc. It will be used later. */
  24         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
  25         if (!obj_list) {
  26                 printk(KERN_ERR "Memory allocation error\n");
  27                 return;
  28         }
  29
  30         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
  31         if (!obj) {
  32                 printk(KERN_ERR "Memory allocation error\n");
  33                 kfree(obj_list);
  34                 return;
  35         }
  36
  37         buf = kmalloc(12, GFP_KERNEL);
  38         if (!buf) {
  39                 printk(KERN_ERR "Memory allocation error\n");
  40                 kfree(obj);
  41                 kfree(obj_list);
  42                 return;
  43         }
  44
  45         buf[0] = ACPI_PDC_REVISION_ID;
  46         buf[1] = 1;
  47         buf[2] = ACPI_PDC_C_CAPABILITY_SMP;
  48
  49         /*
  50          * The default of PDC_SMP_T_SWCOORD bit is set for intel x86 cpu so
  51          * that OSPM is capable of native ACPI throttling software
  52          * coordination using BIOS supplied _TSD info.
  53          */
  54         buf[2] |= ACPI_PDC_SMP_T_SWCOORD;
  55         if (cpu_has(c, X86_FEATURE_EST))
  56                 buf[2] |= ACPI_PDC_EST_CAPABILITY_SWSMP;
  57
  58         if (cpu_has(c, X86_FEATURE_ACPI))
  59                 buf[2] |= ACPI_PDC_T_FFH;
  60
  61         obj->type = ACPI_TYPE_BUFFER;
  62         obj->buffer.length = 12;
  63         obj->buffer.pointer = (u8 *) buf;
  64         obj_list->count = 1;
  65         obj_list->pointer = obj;
  66         pr->pdc = obj_list;
  67
  68         return;
  69 }
  70
  71 /* Initialize _PDC data based on the CPU vendor */
  72 void arch_acpi_processor_init_pdc(struct acpi_processor *pr)
  73 {
  74         struct cpuinfo_x86 *c = &cpu_data(pr->id);
  75
  76         pr->pdc = NULL;
  77         if (c->x86_vendor == X86_VENDOR_INTEL)
  78                 init_intel_pdc(pr, c);
  79
  80         return;
  81 }
  82
  83 EXPORT_SYMBOL(arch_acpi_processor_init_pdc);