3 #include <acpi/acpi_drivers.h>
4 #include <acpi/processor.h>
8 #define PREFIX "ACPI: "
9 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
10 ACPI_MODULE_NAME("processor_pdc");
12 static int set_no_mwait(const struct dmi_system_id
*id
)
14 printk(KERN_NOTICE PREFIX
"%s detected - "
15 "disabling mwait for CPU C-states\n", id
->ident
);
20 static struct dmi_system_id __cpuinitdata processor_idle_dmi_table
[] = {
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
},
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
},
36 static void acpi_set_pdc_bits(u32
*buf
)
38 buf
[0] = ACPI_PDC_REVISION_ID
;
41 /* Enable coordination with firmware's _TSD info */
42 buf
[2] = ACPI_PDC_SMP_T_SWCOORD
;
44 /* Twiddle arch-specific bits needed for _PDC */
45 arch_acpi_set_pdc_bits(buf
);
48 static void acpi_processor_init_pdc(struct acpi_processor
*pr
)
50 struct acpi_object_list
*obj_list
;
51 union acpi_object
*obj
;
56 /* allocate and initialize pdc. It will be used later. */
57 obj_list
= kmalloc(sizeof(struct acpi_object_list
), GFP_KERNEL
);
59 printk(KERN_ERR
"Memory allocation error\n");
63 obj
= kmalloc(sizeof(union acpi_object
), GFP_KERNEL
);
65 printk(KERN_ERR
"Memory allocation error\n");
70 buf
= kmalloc(12, GFP_KERNEL
);
72 printk(KERN_ERR
"Memory allocation error\n");
78 acpi_set_pdc_bits(buf
);
80 obj
->type
= ACPI_TYPE_BUFFER
;
81 obj
->buffer
.length
= 12;
82 obj
->buffer
.pointer
= (u8
*) buf
;
84 obj_list
->pointer
= obj
;
91 * _PDC is required for a BIOS-OS handshake for most of the newer
92 * ACPI processor features.
94 static int acpi_processor_eval_pdc(struct acpi_processor
*pr
)
96 struct acpi_object_list
*pdc_in
= pr
->pdc
;
97 acpi_status status
= AE_OK
;
103 * If mwait is disabled for CPU C-states, the C2C3_FFH access
104 * mode will be disabled in the parameter of _PDC object.
105 * Of course C1_FFH access mode will also be disabled.
107 union acpi_object
*obj
;
110 obj
= pdc_in
->pointer
;
111 buffer
= (u32
*)(obj
->buffer
.pointer
);
112 buffer
[2] &= ~(ACPI_PDC_C_C2C3_FFH
| ACPI_PDC_C_C1_FFH
);
115 status
= acpi_evaluate_object(pr
->handle
, "_PDC", pdc_in
, NULL
);
117 if (ACPI_FAILURE(status
))
118 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
119 "Could not evaluate _PDC, using legacy perf. control.\n"));
124 void acpi_processor_set_pdc(struct acpi_processor
*pr
)
126 if (arch_has_acpi_pdc() == false)
129 acpi_processor_init_pdc(pr
);
130 acpi_processor_eval_pdc(pr
);
131 arch_acpi_processor_cleanup_pdc(pr
);
133 EXPORT_SYMBOL_GPL(acpi_processor_set_pdc
);
136 early_init_pdc(acpi_handle handle
, u32 lvl
, void *context
, void **rv
)
138 struct acpi_processor pr
;
142 /* x86 implementation looks at pr.id to determine some
143 * CPU capabilites. We can just hard code to 0 since we're
144 * assuming the CPUs in the system are homogenous and all
145 * have the same capabilities.
149 acpi_processor_set_pdc(&pr
);
154 void acpi_early_processor_set_pdc(void)
157 * Check whether the system is DMI table. If yes, OSPM
158 * should not use mwait for CPU-states.
160 dmi_check_system(processor_idle_dmi_table
);
162 acpi_walk_namespace(ACPI_TYPE_PROCESSOR
, ACPI_ROOT_OBJECT
,
164 early_init_pdc
, NULL
, NULL
, NULL
);