Merge branch 'for-rmk/samsung6' of git://git.fluff.org/bjdooks/linux into devel-stable
[linux-2.6.git] / drivers / acpi / processor_pdc.c
1 /*
2  * Copyright (C) 2005 Intel Corporation
3  * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
4  *
5  *      Alex Chiang <achiang@hp.com>
6  *      - Unified x86/ia64 implementations
7  *      Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
8  *      - Added _PDC for platforms with Intel CPUs
9  */
10 #include <linux/dmi.h>
11
12 #include <acpi/acpi_drivers.h>
13 #include <acpi/processor.h>
14
15 #include "internal.h"
16
17 #define PREFIX                  "ACPI: "
18 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
19 ACPI_MODULE_NAME("processor_pdc");
20
21 static int set_no_mwait(const struct dmi_system_id *id)
22 {
23         printk(KERN_NOTICE PREFIX "%s detected - "
24                 "disabling mwait for CPU C-states\n", id->ident);
25         idle_nomwait = 1;
26         return 0;
27 }
28
29 static struct dmi_system_id __cpuinitdata processor_idle_dmi_table[] = {
30         {
31         set_no_mwait, "IFL91 board", {
32         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
33         DMI_MATCH(DMI_SYS_VENDOR, "ZEPTO"),
34         DMI_MATCH(DMI_PRODUCT_VERSION, "3215W"),
35         DMI_MATCH(DMI_BOARD_NAME, "IFL91") }, NULL},
36         {
37         set_no_mwait, "Extensa 5220", {
38         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
39         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
40         DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
41         DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
42         {},
43 };
44
45 static void acpi_set_pdc_bits(u32 *buf)
46 {
47         buf[0] = ACPI_PDC_REVISION_ID;
48         buf[1] = 1;
49
50         /* Enable coordination with firmware's _TSD info */
51         buf[2] = ACPI_PDC_SMP_T_SWCOORD;
52
53         /* Twiddle arch-specific bits needed for _PDC */
54         arch_acpi_set_pdc_bits(buf);
55 }
56
57 static struct acpi_object_list *acpi_processor_alloc_pdc(void)
58 {
59         struct acpi_object_list *obj_list;
60         union acpi_object *obj;
61         u32 *buf;
62
63         /* allocate and initialize pdc. It will be used later. */
64         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
65         if (!obj_list) {
66                 printk(KERN_ERR "Memory allocation error\n");
67                 return NULL;
68         }
69
70         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
71         if (!obj) {
72                 printk(KERN_ERR "Memory allocation error\n");
73                 kfree(obj_list);
74                 return NULL;
75         }
76
77         buf = kmalloc(12, GFP_KERNEL);
78         if (!buf) {
79                 printk(KERN_ERR "Memory allocation error\n");
80                 kfree(obj);
81                 kfree(obj_list);
82                 return NULL;
83         }
84
85         acpi_set_pdc_bits(buf);
86
87         obj->type = ACPI_TYPE_BUFFER;
88         obj->buffer.length = 12;
89         obj->buffer.pointer = (u8 *) buf;
90         obj_list->count = 1;
91         obj_list->pointer = obj;
92
93         return obj_list;
94 }
95
96 /*
97  * _PDC is required for a BIOS-OS handshake for most of the newer
98  * ACPI processor features.
99  */
100 static int
101 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
102 {
103         acpi_status status = AE_OK;
104
105         if (idle_nomwait) {
106                 /*
107                  * If mwait is disabled for CPU C-states, the C2C3_FFH access
108                  * mode will be disabled in the parameter of _PDC object.
109                  * Of course C1_FFH access mode will also be disabled.
110                  */
111                 union acpi_object *obj;
112                 u32 *buffer = NULL;
113
114                 obj = pdc_in->pointer;
115                 buffer = (u32 *)(obj->buffer.pointer);
116                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
117
118         }
119         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
120
121         if (ACPI_FAILURE(status))
122                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
123                     "Could not evaluate _PDC, using legacy perf. control.\n"));
124
125         return status;
126 }
127
128 static int early_pdc_done;
129
130 void acpi_processor_set_pdc(acpi_handle handle)
131 {
132         struct acpi_object_list *obj_list;
133
134         if (arch_has_acpi_pdc() == false)
135                 return;
136
137         if (early_pdc_done)
138                 return;
139
140         obj_list = acpi_processor_alloc_pdc();
141         if (!obj_list)
142                 return;
143
144         acpi_processor_eval_pdc(handle, obj_list);
145
146         kfree(obj_list->pointer->buffer.pointer);
147         kfree(obj_list->pointer);
148         kfree(obj_list);
149 }
150 EXPORT_SYMBOL_GPL(acpi_processor_set_pdc);
151
152 static int early_pdc_optin;
153 static int set_early_pdc_optin(const struct dmi_system_id *id)
154 {
155         early_pdc_optin = 1;
156         return 0;
157 }
158
159 static int param_early_pdc_optin(char *s)
160 {
161         early_pdc_optin = 1;
162         return 1;
163 }
164 __setup("acpi_early_pdc_eval", param_early_pdc_optin);
165
166 static struct dmi_system_id __cpuinitdata early_pdc_optin_table[] = {
167         {
168         set_early_pdc_optin, "HP Envy", {
169         DMI_MATCH(DMI_BIOS_VENDOR, "Hewlett-Packard"),
170         DMI_MATCH(DMI_PRODUCT_NAME, "HP Envy") }, NULL},
171         {
172         set_early_pdc_optin, "HP Pavilion dv6", {
173         DMI_MATCH(DMI_BIOS_VENDOR, "Hewlett-Packard"),
174         DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv6") }, NULL},
175         {
176         set_early_pdc_optin, "HP Pavilion dv7", {
177         DMI_MATCH(DMI_BIOS_VENDOR, "Hewlett-Packard"),
178         DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv7") }, NULL},
179         {},
180 };
181
182 static acpi_status
183 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
184 {
185         acpi_processor_set_pdc(handle);
186         return AE_OK;
187 }
188
189 void __init acpi_early_processor_set_pdc(void)
190 {
191         /*
192          * Check whether the system is DMI table. If yes, OSPM
193          * should not use mwait for CPU-states.
194          */
195         dmi_check_system(processor_idle_dmi_table);
196
197         /*
198          * Allow systems to opt-in to early _PDC evaluation.
199          */
200         dmi_check_system(early_pdc_optin_table);
201         if (!early_pdc_optin)
202                 return;
203
204         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
205                             ACPI_UINT32_MAX,
206                             early_init_pdc, NULL, NULL, NULL);
207
208         early_pdc_done = 1;
209 }