2 * Copyright (C) 2005 Intel Corporation
3 * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
4 * - Added _PDC for platforms with Intel CPUs
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/acpi.h>
12 #include <acpi/processor.h>
15 static void init_intel_pdc(struct acpi_processor *pr, struct cpuinfo_x86 *c)
17 struct acpi_object_list *obj_list;
18 union acpi_object *obj;
21 /* allocate and initialize pdc. It will be used later. */
22 obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
24 printk(KERN_ERR "Memory allocation error\n");
28 obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
30 printk(KERN_ERR "Memory allocation error\n");
35 buf = kmalloc(12, GFP_KERNEL);
37 printk(KERN_ERR "Memory allocation error\n");
43 buf[0] = ACPI_PDC_REVISION_ID;
45 buf[2] = ACPI_PDC_C_CAPABILITY_SMP;
48 * The default of PDC_SMP_T_SWCOORD bit is set for intel x86 cpu so
49 * that OSPM is capable of native ACPI throttling software
50 * coordination using BIOS supplied _TSD info.
52 buf[2] |= ACPI_PDC_SMP_T_SWCOORD;
53 if (cpu_has(c, X86_FEATURE_EST))
54 buf[2] |= ACPI_PDC_EST_CAPABILITY_SWSMP;
56 if (cpu_has(c, X86_FEATURE_ACPI))
57 buf[2] |= ACPI_PDC_T_FFH;
60 * If mwait/monitor is unsupported, C2/C3_FFH will be disabled
62 if (!cpu_has(c, X86_FEATURE_MWAIT))
63 buf[2] &= ~(ACPI_PDC_C_C2C3_FFH);
65 obj->type = ACPI_TYPE_BUFFER;
66 obj->buffer.length = 12;
67 obj->buffer.pointer = (u8 *) buf;
69 obj_list->pointer = obj;
75 /* Initialize _PDC data based on the CPU vendor */
76 void arch_acpi_processor_init_pdc(struct acpi_processor *pr)
78 struct cpuinfo_x86 *c = &cpu_data(pr->id);
81 if (c->x86_vendor == X86_VENDOR_INTEL)
82 init_intel_pdc(pr, c);
87 EXPORT_SYMBOL(arch_acpi_processor_init_pdc);