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 <linux/pci-aspm.h>
  15 #include <acpi/acpi.h>
  16 #include <acpi/acnamesp.h>
  17 #include <acpi/acresrc.h>
  18 #include <acpi/acpi_bus.h>
  19
  20 #include <linux/pci-acpi.h>
  21 #include "pci.h"
  22
  23 struct acpi_osc_data {
  24         acpi_handle handle;
  25         u32 support_set;
  26         u32 control_set;
  27         int is_queried;
  28         u32 query_result;
  29         struct list_head sibiling;
  30 };
  31 static LIST_HEAD(acpi_osc_data_list);
  32
  33 struct acpi_osc_args {
  34         u32 capbuf[3];
  35         u32 query_result;
  36 };
  37
  38 static DEFINE_MUTEX(pci_acpi_lock);
  39
  40 static struct acpi_osc_data *acpi_get_osc_data(acpi_handle handle)
  41 {
  42         struct acpi_osc_data *data;
  43
  44         list_for_each_entry(data, &acpi_osc_data_list, sibiling) {
  45                 if (data->handle == handle)
  46                         return data;
  47         }
  48         data = kzalloc(sizeof(*data), GFP_KERNEL);
  49         if (!data)
  50                 return NULL;
  51         INIT_LIST_HEAD(&data->sibiling);
  52         data->handle = handle;
  53         list_add_tail(&data->sibiling, &acpi_osc_data_list);
  54         return data;
  55 }
  56
  57 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
  58                           0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
  59
  60 static acpi_status acpi_run_osc(acpi_handle handle,
  61                                 struct acpi_osc_args *osc_args)
  62 {
  63         acpi_status status;
  64         struct acpi_object_list input;
  65         union acpi_object in_params[4];
  66         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
  67         union acpi_object *out_obj;
  68         u32 errors, flags = osc_args->capbuf[OSC_QUERY_TYPE];
  69
  70         /* Setting up input parameters */
  71         input.count = 4;
  72         input.pointer = in_params;
  73         in_params[0].type               = ACPI_TYPE_BUFFER;
  74         in_params[0].buffer.length      = 16;
  75         in_params[0].buffer.pointer     = OSC_UUID;
  76         in_params[1].type               = ACPI_TYPE_INTEGER;
  77         in_params[1].integer.value      = 1;
  78         in_params[2].type               = ACPI_TYPE_INTEGER;
  79         in_params[2].integer.value      = 3;
  80         in_params[3].type               = ACPI_TYPE_BUFFER;
  81         in_params[3].buffer.length      = 12;
  82         in_params[3].buffer.pointer     = (u8 *)osc_args->capbuf;
  83
  84         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
  85         if (ACPI_FAILURE(status))
  86                 return status;
  87
  88         if (!output.length)
  89                 return AE_NULL_OBJECT;
  90
  91         out_obj = output.pointer;
  92         if (out_obj->type != ACPI_TYPE_BUFFER) {
  93                 printk(KERN_DEBUG "Evaluate _OSC returns wrong type\n");
  94                 status = AE_TYPE;
  95                 goto out_kfree;
  96         }
  97         /* Need to ignore the bit0 in result code */
  98         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
  99         if (errors) {
 100                 if (errors & OSC_REQUEST_ERROR)
 101                         printk(KERN_DEBUG "_OSC request fails\n");
 102                 if (errors & OSC_INVALID_UUID_ERROR)
 103                         printk(KERN_DEBUG "_OSC invalid UUID\n");
 104                 if (errors & OSC_INVALID_REVISION_ERROR)
 105                         printk(KERN_DEBUG "_OSC invalid revision\n");
 106                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
 107                         if (flags & OSC_QUERY_ENABLE)
 108                                 goto out_success;
 109                         printk(KERN_DEBUG "_OSC FW not grant req. control\n");
 110                         status = AE_SUPPORT;
 111                         goto out_kfree;
 112                 }
 113                 status = AE_ERROR;
 114                 goto out_kfree;
 115         }
 116 out_success:
 117         if (flags & OSC_QUERY_ENABLE)
 118                 osc_args->query_result =
 119                         *((u32 *)(out_obj->buffer.pointer + 8));
 120         status = AE_OK;
 121
 122 out_kfree:
 123         kfree(output.pointer);
 124         return status;
 125 }
 126
 127 static acpi_status __acpi_query_osc(u32 flags, struct acpi_osc_data *osc_data)
 128 {
 129         acpi_status status;
 130         u32 support_set;
 131         struct acpi_osc_args osc_args;
 132
 133         /* do _OSC query for all possible controls */
 134         support_set = osc_data->support_set | (flags & OSC_SUPPORT_MASKS);
 135         osc_args.capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 136         osc_args.capbuf[OSC_SUPPORT_TYPE] = support_set;
 137         osc_args.capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
 138
 139         status = acpi_run_osc(osc_data->handle, &osc_args);
 140         if (ACPI_SUCCESS(status)) {
 141                 osc_data->support_set = support_set;
 142                 osc_data->query_result = osc_args.query_result;
 143                 osc_data->is_queried = 1;
 144         }
 145
 146         return status;
 147 }
 148
 149 /*
 150  * pci_acpi_osc_support: Invoke _OSC indicating support for the given feature
 151  * @flags: Bitmask of flags to support
 152  *
 153  * See the ACPI spec for the definition of the flags
 154  */
 155 int pci_acpi_osc_support(acpi_handle handle, u32 flags)
 156 {
 157         acpi_status status;
 158         acpi_handle tmp;
 159         struct acpi_osc_data *osc_data;
 160         int rc = 0;
 161
 162         status = acpi_get_handle(handle, "_OSC", &tmp);
 163         if (ACPI_FAILURE(status))
 164                 return -ENOTTY;
 165
 166         mutex_lock(&pci_acpi_lock);
 167         osc_data = acpi_get_osc_data(handle);
 168         if (!osc_data) {
 169                 printk(KERN_ERR "acpi osc data array is full\n");
 170                 rc = -ENOMEM;
 171                 goto out;
 172         }
 173
 174         __acpi_query_osc(flags, osc_data);
 175 out:
 176         mutex_unlock(&pci_acpi_lock);
 177         return rc;
 178 }
 179
 180 /**
 181  * pci_osc_control_set - commit requested control to Firmware
 182  * @handle: acpi_handle for the target ACPI object
 183  * @flags: driver's requested control bits
 184  *
 185  * Attempt to take control from Firmware on requested control bits.
 186  **/
 187 acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
 188 {
 189         acpi_status status;
 190         u32 ctrlset, control_set;
 191         acpi_handle tmp;
 192         struct acpi_osc_data *osc_data;
 193         struct acpi_osc_args osc_args;
 194
 195         status = acpi_get_handle(handle, "_OSC", &tmp);
 196         if (ACPI_FAILURE(status))
 197                 return status;
 198
 199         mutex_lock(&pci_acpi_lock);
 200         osc_data = acpi_get_osc_data(handle);
 201         if (!osc_data) {
 202                 printk(KERN_ERR "acpi osc data array is full\n");
 203                 status = AE_ERROR;
 204                 goto out;
 205         }
 206
 207         ctrlset = (flags & OSC_CONTROL_MASKS);
 208         if (!ctrlset) {
 209                 status = AE_TYPE;
 210                 goto out;
 211         }
 212
 213         if (!osc_data->is_queried) {
 214                 status = __acpi_query_osc(osc_data->support_set, osc_data);
 215                 if (ACPI_FAILURE(status))
 216                         goto out;
 217         }
 218
 219         if ((osc_data->query_result & ctrlset) != ctrlset) {
 220                 status = AE_SUPPORT;
 221                 goto out;
 222         }
 223
 224         control_set = osc_data->control_set | ctrlset;
 225         osc_args.capbuf[OSC_QUERY_TYPE] = 0;
 226         osc_args.capbuf[OSC_SUPPORT_TYPE] = osc_data->support_set;
 227         osc_args.capbuf[OSC_CONTROL_TYPE] = control_set;
 228         status = acpi_run_osc(handle, &osc_args);
 229         if (ACPI_SUCCESS(status))
 230                 osc_data->control_set = control_set;
 231 out:
 232         mutex_unlock(&pci_acpi_lock);
 233         return status;
 234 }
 235 EXPORT_SYMBOL(pci_osc_control_set);
 236
 237 /*
 238  * _SxD returns the D-state with the highest power
 239  * (lowest D-state number) supported in the S-state "x".
 240  *
 241  * If the devices does not have a _PRW
 242  * (Power Resources for Wake) supporting system wakeup from "x"
 243  * then the OS is free to choose a lower power (higher number
 244  * D-state) than the return value from _SxD.
 245  *
 246  * But if _PRW is enabled at S-state "x", the OS
 247  * must not choose a power lower than _SxD --
 248  * unless the device has an _SxW method specifying
 249  * the lowest power (highest D-state number) the device
 250  * may enter while still able to wake the system.
 251  *
 252  * ie. depending on global OS policy:
 253  *
 254  * if (_PRW at S-state x)
 255  *      choose from highest power _SxD to lowest power _SxW
 256  * else // no _PRW at S-state x
 257  *      choose highest power _SxD or any lower power
 258  */
 259
 260 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
 261 {
 262         int acpi_state;
 263
 264         acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL);
 265         if (acpi_state < 0)
 266                 return PCI_POWER_ERROR;
 267
 268         switch (acpi_state) {
 269         case ACPI_STATE_D0:
 270                 return PCI_D0;
 271         case ACPI_STATE_D1:
 272                 return PCI_D1;
 273         case ACPI_STATE_D2:
 274                 return PCI_D2;
 275         case ACPI_STATE_D3:
 276                 return PCI_D3hot;
 277         }
 278         return PCI_POWER_ERROR;
 279 }
 280
 281 static bool acpi_pci_power_manageable(struct pci_dev *dev)
 282 {
 283         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 284
 285         return handle ? acpi_bus_power_manageable(handle) : false;
 286 }
 287
 288 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 289 {
 290         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 291         acpi_handle tmp;
 292         static const u8 state_conv[] = {
 293                 [PCI_D0] = ACPI_STATE_D0,
 294                 [PCI_D1] = ACPI_STATE_D1,
 295                 [PCI_D2] = ACPI_STATE_D2,
 296                 [PCI_D3hot] = ACPI_STATE_D3,
 297                 [PCI_D3cold] = ACPI_STATE_D3
 298         };
 299         int error = -EINVAL;
 300
 301         /* If the ACPI device has _EJ0, ignore the device */
 302         if (!handle || ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0", &tmp)))
 303                 return -ENODEV;
 304
 305         switch (state) {
 306         case PCI_D0:
 307         case PCI_D1:
 308         case PCI_D2:
 309         case PCI_D3hot:
 310         case PCI_D3cold:
 311                 error = acpi_bus_set_power(handle, state_conv[state]);
 312         }
 313
 314         if (!error)
 315                 dev_printk(KERN_INFO, &dev->dev,
 316                                 "power state changed by ACPI to D%d\n", state);
 317
 318         return error;
 319 }
 320
 321 static bool acpi_pci_can_wakeup(struct pci_dev *dev)
 322 {
 323         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 324
 325         return handle ? acpi_bus_can_wakeup(handle) : false;
 326 }
 327
 328 static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
 329 {
 330         int error = acpi_pm_device_sleep_wake(&dev->dev, enable);
 331
 332         if (!error)
 333                 dev_printk(KERN_INFO, &dev->dev,
 334                                 "wake-up capability %s by ACPI\n",
 335                                 enable ? "enabled" : "disabled");
 336         return error;
 337 }
 338
 339 static struct pci_platform_pm_ops acpi_pci_platform_pm = {
 340         .is_manageable = acpi_pci_power_manageable,
 341         .set_state = acpi_pci_set_power_state,
 342         .choose_state = acpi_pci_choose_state,
 343         .can_wakeup = acpi_pci_can_wakeup,
 344         .sleep_wake = acpi_pci_sleep_wake,
 345 };
 346
 347 /* ACPI bus type */
 348 static int acpi_pci_find_device(struct device *dev, acpi_handle *handle)
 349 {
 350         struct pci_dev * pci_dev;
 351         acpi_integer    addr;
 352
 353         pci_dev = to_pci_dev(dev);
 354         /* Please ref to ACPI spec for the syntax of _ADR */
 355         addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
 356         *handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev->parent), addr);
 357         if (!*handle)
 358                 return -ENODEV;
 359         return 0;
 360 }
 361
 362 static int acpi_pci_find_root_bridge(struct device *dev, acpi_handle *handle)
 363 {
 364         int num;
 365         unsigned int seg, bus;
 366
 367         /*
 368          * The string should be the same as root bridge's name
 369          * Please look at 'pci_scan_bus_parented'
 370          */
 371         num = sscanf(dev_name(dev), "pci%04x:%02x", &seg, &bus);
 372         if (num != 2)
 373                 return -ENODEV;
 374         *handle = acpi_get_pci_rootbridge_handle(seg, bus);
 375         if (!*handle)
 376                 return -ENODEV;
 377         return 0;
 378 }
 379
 380 static struct acpi_bus_type acpi_pci_bus = {
 381         .bus = &pci_bus_type,
 382         .find_device = acpi_pci_find_device,
 383         .find_bridge = acpi_pci_find_root_bridge,
 384 };
 385
 386 static int __init acpi_pci_init(void)
 387 {
 388         int ret;
 389
 390         if (acpi_gbl_FADT.boot_flags & BAF_MSI_NOT_SUPPORTED) {
 391                 printk(KERN_INFO"ACPI FADT declares the system doesn't support MSI, so disable it\n");
 392                 pci_no_msi();
 393         }
 394
 395         if (acpi_gbl_FADT.boot_flags & BAF_PCIE_ASPM_CONTROL) {
 396                 printk(KERN_INFO"ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
 397                 pcie_no_aspm();
 398         }
 399
 400         ret = register_acpi_bus_type(&acpi_pci_bus);
 401         if (ret)
 402                 return 0;
 403         pci_set_platform_pm(&acpi_pci_platform_pm);
 404         return 0;
 405 }
 406 arch_initcall(acpi_pci_init);