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