drivers/pci/pci-acpi.c

   1 /*
   2  * File:        pci-acpi.c
   3  * Purpose:     Provide PCI support in ACPI
   4  *
   5  * Copyright (C) 2005 David Shaohua Li <shaohua.li@intel.com>
   6  * Copyright (C) 2004 Tom Long Nguyen <tom.l.nguyen@intel.com>
   7  * Copyright (C) 2004 Intel Corp.
   8  */
   9
  10 #include <linux/delay.h>
  11 #include <linux/init.h>
  12 #include <linux/pci.h>
  13 #include <linux/module.h>
  14 #include <acpi/acpi.h>
  15 #include <acpi/acnamesp.h>
  16 #include <acpi/acresrc.h>
  17 #include <acpi/acpi_bus.h>
  18
  19 #include <linux/pci-acpi.h>
  20 #include "pci.h"
  21
  22 struct acpi_osc_data {
  23         acpi_handle handle;
  24         u32 support_set;
  25         u32 control_set;
  26         int is_queried;
  27         u32 query_result;
  28         struct list_head sibiling;
  29 };
  30 static LIST_HEAD(acpi_osc_data_list);
  31
  32 struct acpi_osc_args {
  33         u32 capbuf[3];
  34         u32 query_result;
  35 };
  36
  37 static struct acpi_osc_data *acpi_get_osc_data(acpi_handle handle)
  38 {
  39         struct acpi_osc_data *data;
  40
  41         list_for_each_entry(data, &acpi_osc_data_list, sibiling) {
  42                 if (data->handle == handle)
  43                         return data;
  44         }
  45         data = kzalloc(sizeof(*data), GFP_KERNEL);
  46         if (!data)
  47                 return NULL;
  48         INIT_LIST_HEAD(&data->sibiling);
  49         data->handle = handle;
  50         list_add_tail(&data->sibiling, &acpi_osc_data_list);
  51         return data;
  52 }
  53
  54 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
  55                           0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
  56
  57 static acpi_status acpi_run_osc(acpi_handle handle,
  58                                 struct acpi_osc_args *osc_args)
  59 {
  60         acpi_status status;
  61         struct acpi_object_list input;
  62         union acpi_object in_params[4];
  63         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
  64         union acpi_object *out_obj;
  65         u32 osc_dw0, flags = osc_args->capbuf[OSC_QUERY_TYPE];
  66
  67         /* Setting up input parameters */
  68         input.count = 4;
  69         input.pointer = in_params;
  70         in_params[0].type               = ACPI_TYPE_BUFFER;
  71         in_params[0].buffer.length      = 16;
  72         in_params[0].buffer.pointer     = OSC_UUID;
  73         in_params[1].type               = ACPI_TYPE_INTEGER;
  74         in_params[1].integer.value      = 1;
  75         in_params[2].type               = ACPI_TYPE_INTEGER;
  76         in_params[2].integer.value      = 3;
  77         in_params[3].type               = ACPI_TYPE_BUFFER;
  78         in_params[3].buffer.length      = 12;
  79         in_params[3].buffer.pointer     = (u8 *)osc_args->capbuf;
  80
  81         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
  82         if (ACPI_FAILURE(status))
  83                 return status;
  84
  85         out_obj = output.pointer;
  86         if (out_obj->type != ACPI_TYPE_BUFFER) {
  87                 printk(KERN_DEBUG "Evaluate _OSC returns wrong type\n");
  88                 status = AE_TYPE;
  89                 goto out_kfree;
  90         }
  91         osc_dw0 = *((u32 *)out_obj->buffer.pointer);
  92         if (osc_dw0) {
  93                 if (osc_dw0 & OSC_REQUEST_ERROR)
  94                         printk(KERN_DEBUG "_OSC request fails\n");
  95                 if (osc_dw0 & OSC_INVALID_UUID_ERROR)
  96                         printk(KERN_DEBUG "_OSC invalid UUID\n");
  97                 if (osc_dw0 & OSC_INVALID_REVISION_ERROR)
  98                         printk(KERN_DEBUG "_OSC invalid revision\n");
  99                 if (osc_dw0 & OSC_CAPABILITIES_MASK_ERROR) {
 100                         if (flags & OSC_QUERY_ENABLE)
 101                                 goto out_success;
 102                         printk(KERN_DEBUG "_OSC FW not grant req. control\n");
 103                         status = AE_SUPPORT;
 104                         goto out_kfree;
 105                 }
 106                 status = AE_ERROR;
 107                 goto out_kfree;
 108         }
 109 out_success:
 110         if (flags & OSC_QUERY_ENABLE)
 111                 osc_args->query_result =
 112                         *((u32 *)(out_obj->buffer.pointer + 8));
 113         status = AE_OK;
 114
 115 out_kfree:
 116         kfree(output.pointer);
 117         return status;
 118 }
 119
 120 static acpi_status acpi_query_osc(acpi_handle handle,
 121                                   u32 level, void *context, void **retval)
 122 {
 123         acpi_status status;
 124         struct acpi_osc_data *osc_data;
 125         u32 flags = (unsigned long)context, support_set;
 126         acpi_handle tmp;
 127         struct acpi_osc_args osc_args;
 128
 129         status = acpi_get_handle(handle, "_OSC", &tmp);
 130         if (ACPI_FAILURE(status))
 131                 return status;
 132
 133         osc_data = acpi_get_osc_data(handle);
 134         if (!osc_data) {
 135                 printk(KERN_ERR "acpi osc data array is full\n");
 136                 return AE_ERROR;
 137         }
 138
 139         /* do _OSC query for all possible controls */
 140         support_set = osc_data->support_set | (flags & OSC_SUPPORT_MASKS);
 141         osc_args.capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 142         osc_args.capbuf[OSC_SUPPORT_TYPE] = support_set;
 143         osc_args.capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
 144
 145         status = acpi_run_osc(handle, &osc_args);
 146         if (ACPI_SUCCESS(status)) {
 147                 osc_data->support_set = support_set;
 148                 osc_data->query_result = osc_args.query_result;
 149                 osc_data->is_queried = 1;
 150         }
 151
 152         return status;
 153 }
 154
 155 /**
 156  * __pci_osc_support_set - register OS support to Firmware
 157  * @flags: OS support bits
 158  * @hid: hardware ID
 159  *
 160  * Update OS support fields and doing a _OSC Query to obtain an update
 161  * from Firmware on supported control bits.
 162  **/
 163 acpi_status __pci_osc_support_set(u32 flags, const char *hid)
 164 {
 165         if (!(flags & OSC_SUPPORT_MASKS))
 166                 return AE_TYPE;
 167
 168         acpi_get_devices(hid, acpi_query_osc,
 169                          (void *)(unsigned long)flags, NULL);
 170         return AE_OK;
 171 }
 172
 173 /**
 174  * pci_osc_control_set - commit requested control to Firmware
 175  * @handle: acpi_handle for the target ACPI object
 176  * @flags: driver's requested control bits
 177  *
 178  * Attempt to take control from Firmware on requested control bits.
 179  **/
 180 acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
 181 {
 182         acpi_status status;
 183         u32 ctrlset, control_set;
 184         acpi_handle tmp;
 185         struct acpi_osc_data *osc_data;
 186         struct acpi_osc_args osc_args;
 187
 188         status = acpi_get_handle(handle, "_OSC", &tmp);
 189         if (ACPI_FAILURE(status))
 190                 return status;
 191
 192         osc_data = acpi_get_osc_data(handle);
 193         if (!osc_data) {
 194                 printk(KERN_ERR "acpi osc data array is full\n");
 195                 return AE_ERROR;
 196         }
 197
 198         ctrlset = (flags & OSC_CONTROL_MASKS);
 199         if (!ctrlset)
 200                 return AE_TYPE;
 201
 202         if (osc_data->is_queried &&
 203             ((osc_data->query_result & ctrlset) != ctrlset))
 204                 return AE_SUPPORT;
 205
 206         control_set = osc_data->control_set | ctrlset;
 207         osc_args.capbuf[OSC_QUERY_TYPE] = 0;
 208         osc_args.capbuf[OSC_SUPPORT_TYPE] = osc_data->support_set;
 209         osc_args.capbuf[OSC_CONTROL_TYPE] = control_set;
 210         status = acpi_run_osc(handle, &osc_args);
 211         if (ACPI_SUCCESS(status))
 212                 osc_data->control_set = control_set;
 213
 214         return status;
 215 }
 216 EXPORT_SYMBOL(pci_osc_control_set);
 217
 218 /*
 219  * _SxD returns the D-state with the highest power
 220  * (lowest D-state number) supported in the S-state "x".
 221  *
 222  * If the devices does not have a _PRW
 223  * (Power Resources for Wake) supporting system wakeup from "x"
 224  * then the OS is free to choose a lower power (higher number
 225  * D-state) than the return value from _SxD.
 226  *
 227  * But if _PRW is enabled at S-state "x", the OS
 228  * must not choose a power lower than _SxD --
 229  * unless the device has an _SxW method specifying
 230  * the lowest power (highest D-state number) the device
 231  * may enter while still able to wake the system.
 232  *
 233  * ie. depending on global OS policy:
 234  *
 235  * if (_PRW at S-state x)
 236  *      choose from highest power _SxD to lowest power _SxW
 237  * else // no _PRW at S-state x
 238  *      choose highest power _SxD or any lower power
 239  */
 240
 241 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
 242 {
 243         int acpi_state;
 244
 245         acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL);
 246         if (acpi_state < 0)
 247                 return PCI_POWER_ERROR;
 248
 249         switch (acpi_state) {
 250         case ACPI_STATE_D0:
 251                 return PCI_D0;
 252         case ACPI_STATE_D1:
 253                 return PCI_D1;
 254         case ACPI_STATE_D2:
 255                 return PCI_D2;
 256         case ACPI_STATE_D3:
 257                 return PCI_D3hot;
 258         }
 259         return PCI_POWER_ERROR;
 260 }
 261
 262 static bool acpi_pci_power_manageable(struct pci_dev *dev)
 263 {
 264         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 265
 266         return handle ? acpi_bus_power_manageable(handle) : false;
 267 }
 268
 269 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 270 {
 271         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 272         acpi_handle tmp;
 273         static const u8 state_conv[] = {
 274                 [PCI_D0] = ACPI_STATE_D0,
 275                 [PCI_D1] = ACPI_STATE_D1,
 276                 [PCI_D2] = ACPI_STATE_D2,
 277                 [PCI_D3hot] = ACPI_STATE_D3,
 278                 [PCI_D3cold] = ACPI_STATE_D3
 279         };
 280
 281         if (!handle)
 282                 return -ENODEV;
 283         /* If the ACPI device has _EJ0, ignore the device */
 284         if (ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0", &tmp)))
 285                 return 0;
 286
 287         switch (state) {
 288         case PCI_D0:
 289         case PCI_D1:
 290         case PCI_D2:
 291         case PCI_D3hot:
 292         case PCI_D3cold:
 293                 return acpi_bus_set_power(handle, state_conv[state]);
 294         }
 295         return -EINVAL;
 296 }
 297
 298 static struct pci_platform_pm_ops acpi_pci_platform_pm = {
 299         .is_manageable = acpi_pci_power_manageable,
 300         .set_state = acpi_pci_set_power_state,
 301         .choose_state = acpi_pci_choose_state,
 302 };
 303
 304 /* ACPI bus type */
 305 static int acpi_pci_find_device(struct device *dev, acpi_handle *handle)
 306 {
 307         struct pci_dev * pci_dev;
 308         acpi_integer    addr;
 309
 310         pci_dev = to_pci_dev(dev);
 311         /* Please ref to ACPI spec for the syntax of _ADR */
 312         addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
 313         *handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev->parent), addr);
 314         if (!*handle)
 315                 return -ENODEV;
 316         return 0;
 317 }
 318
 319 static int acpi_pci_find_root_bridge(struct device *dev, acpi_handle *handle)
 320 {
 321         int num;
 322         unsigned int seg, bus;
 323
 324         /*
 325          * The string should be the same as root bridge's name
 326          * Please look at 'pci_scan_bus_parented'
 327          */
 328         num = sscanf(dev->bus_id, "pci%04x:%02x", &seg, &bus);
 329         if (num != 2)
 330                 return -ENODEV;
 331         *handle = acpi_get_pci_rootbridge_handle(seg, bus);
 332         if (!*handle)
 333                 return -ENODEV;
 334         return 0;
 335 }
 336
 337 static struct acpi_bus_type acpi_pci_bus = {
 338         .bus = &pci_bus_type,
 339         .find_device = acpi_pci_find_device,
 340         .find_bridge = acpi_pci_find_root_bridge,
 341 };
 342
 343 static int __init acpi_pci_init(void)
 344 {
 345         int ret;
 346
 347         if (acpi_gbl_FADT.boot_flags & BAF_MSI_NOT_SUPPORTED) {
 348                 printk(KERN_INFO"ACPI FADT declares the system doesn't support MSI, so disable it\n");
 349                 pci_no_msi();
 350         }
 351         ret = register_acpi_bus_type(&acpi_pci_bus);
 352         if (ret)
 353                 return 0;
 354         pci_set_platform_pm(&acpi_pci_platform_pm);
 355         return 0;
 356 }
 357 arch_initcall(acpi_pci_init);