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