blob: 931e735e9e37812e27972f7443dbe393690c1d6a [file] [log] [blame]
Alex Chiang78f16992009-12-20 12:19:09 -07001#include <linux/dmi.h>
2
3#include <acpi/acpi_drivers.h>
4#include <acpi/processor.h>
5
6#include "internal.h"
7
8#define PREFIX "ACPI: "
9#define _COMPONENT ACPI_PROCESSOR_COMPONENT
10ACPI_MODULE_NAME("processor_pdc");
11
12static int set_no_mwait(const struct dmi_system_id *id)
13{
14 printk(KERN_NOTICE PREFIX "%s detected - "
15 "disabling mwait for CPU C-states\n", id->ident);
16 idle_nomwait = 1;
17 return 0;
18}
19
20static struct dmi_system_id __cpuinitdata processor_idle_dmi_table[] = {
21 {
22 set_no_mwait, "IFL91 board", {
23 DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
24 DMI_MATCH(DMI_SYS_VENDOR, "ZEPTO"),
25 DMI_MATCH(DMI_PRODUCT_VERSION, "3215W"),
26 DMI_MATCH(DMI_BOARD_NAME, "IFL91") }, NULL},
27 {
28 set_no_mwait, "Extensa 5220", {
29 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
30 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
31 DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
32 DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
33 {},
34};
35
36/*
37 * _PDC is required for a BIOS-OS handshake for most of the newer
38 * ACPI processor features.
39 */
40static int acpi_processor_eval_pdc(struct acpi_processor *pr)
41{
42 struct acpi_object_list *pdc_in = pr->pdc;
43 acpi_status status = AE_OK;
44
45 if (!pdc_in)
46 return status;
47 if (idle_nomwait) {
48 /*
49 * If mwait is disabled for CPU C-states, the C2C3_FFH access
50 * mode will be disabled in the parameter of _PDC object.
51 * Of course C1_FFH access mode will also be disabled.
52 */
53 union acpi_object *obj;
54 u32 *buffer = NULL;
55
56 obj = pdc_in->pointer;
57 buffer = (u32 *)(obj->buffer.pointer);
58 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
59
60 }
61 status = acpi_evaluate_object(pr->handle, "_PDC", pdc_in, NULL);
62
63 if (ACPI_FAILURE(status))
64 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
65 "Could not evaluate _PDC, using legacy perf. control.\n"));
66
67 return status;
68}
69
70void acpi_processor_set_pdc(struct acpi_processor *pr)
71{
Alex Chiang1d9cb472009-12-20 12:19:14 -070072 if (arch_has_acpi_pdc() == false)
73 return;
74
Alex Chiang78f16992009-12-20 12:19:09 -070075 arch_acpi_processor_init_pdc(pr);
76 acpi_processor_eval_pdc(pr);
77 arch_acpi_processor_cleanup_pdc(pr);
78}
79EXPORT_SYMBOL_GPL(acpi_processor_set_pdc);
80
81static acpi_status
82early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
83{
84 struct acpi_processor pr;
85
86 pr.handle = handle;
87
88 /* x86 implementation looks at pr.id to determine some
89 * CPU capabilites. We can just hard code to 0 since we're
90 * assuming the CPUs in the system are homogenous and all
91 * have the same capabilities.
92 */
93 pr.id = 0;
94
95 acpi_processor_set_pdc(&pr);
96
97 return AE_OK;
98}
99
100void acpi_early_processor_set_pdc(void)
101{
102 /*
103 * Check whether the system is DMI table. If yes, OSPM
104 * should not use mwait for CPU-states.
105 */
106 dmi_check_system(processor_idle_dmi_table);
107
108 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
109 ACPI_UINT32_MAX,
110 early_init_pdc, NULL, NULL, NULL);
111}