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/acpi_bus.h>
  17
  18 #include <linux/pci-acpi.h>
  19 #include "pci.h"
  20
  21 struct acpi_osc_data {
  22         acpi_handle handle;
  23         u32 support_set;
  24         u32 control_set;
  25         struct list_head sibiling;
  26 };
  27 static LIST_HEAD(acpi_osc_data_list);
  28
  29 struct acpi_osc_args {
  30         u32 capbuf[3];
  31         u32 ctrl_result;
  32 };
  33
  34 static DEFINE_MUTEX(pci_acpi_lock);
  35
  36 static struct acpi_osc_data *acpi_get_osc_data(acpi_handle handle)
  37 {
  38         struct acpi_osc_data *data;
  39
  40         list_for_each_entry(data, &acpi_osc_data_list, sibiling) {
  41                 if (data->handle == handle)
  42                         return data;
  43         }
  44         data = kzalloc(sizeof(*data), GFP_KERNEL);
  45         if (!data)
  46                 return NULL;
  47         INIT_LIST_HEAD(&data->sibiling);
  48         data->handle = handle;
  49         list_add_tail(&data->sibiling, &acpi_osc_data_list);
  50         return data;
  51 }
  52
  53 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
  54                           0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
  55
  56 static acpi_status acpi_run_osc(acpi_handle handle,
  57                                 struct acpi_osc_args *osc_args)
  58 {
  59         acpi_status status;
  60         struct acpi_object_list input;
  61         union acpi_object in_params[4];
  62         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
  63         union acpi_object *out_obj;
  64         u32 errors, flags = osc_args->capbuf[OSC_QUERY_TYPE];
  65
  66         /* Setting up input parameters */
  67         input.count = 4;
  68         input.pointer = in_params;
  69         in_params[0].type               = ACPI_TYPE_BUFFER;
  70         in_params[0].buffer.length      = 16;
  71         in_params[0].buffer.pointer     = OSC_UUID;
  72         in_params[1].type               = ACPI_TYPE_INTEGER;
  73         in_params[1].integer.value      = 1;
  74         in_params[2].type               = ACPI_TYPE_INTEGER;
  75         in_params[2].integer.value      = 3;
  76         in_params[3].type               = ACPI_TYPE_BUFFER;
  77         in_params[3].buffer.length      = 12;
  78         in_params[3].buffer.pointer     = (u8 *)osc_args->capbuf;
  79
  80         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
  81         if (ACPI_FAILURE(status))
  82                 return status;
  83
  84         if (!output.length)
  85                 return AE_NULL_OBJECT;
  86
  87         out_obj = output.pointer;
  88         if (out_obj->type != ACPI_TYPE_BUFFER) {
  89                 printk(KERN_DEBUG "Evaluate _OSC returns wrong type\n");
  90                 status = AE_TYPE;
  91                 goto out_kfree;
  92         }
  93         /* Need to ignore the bit0 in result code */
  94         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
  95         if (errors) {
  96                 if (errors & OSC_REQUEST_ERROR)
  97                         printk(KERN_DEBUG "_OSC request fails\n");
  98                 if (errors & OSC_INVALID_UUID_ERROR)
  99                         printk(KERN_DEBUG "_OSC invalid UUID\n");
 100                 if (errors & OSC_INVALID_REVISION_ERROR)
 101                         printk(KERN_DEBUG "_OSC invalid revision\n");
 102                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
 103                         if (flags & OSC_QUERY_ENABLE)
 104                                 goto out_success;
 105                         printk(KERN_DEBUG "_OSC FW not grant req. control\n");
 106                         status = AE_SUPPORT;
 107                         goto out_kfree;
 108                 }
 109                 status = AE_ERROR;
 110                 goto out_kfree;
 111         }
 112 out_success:
 113         osc_args->ctrl_result =
 114                 *((u32 *)(out_obj->buffer.pointer + 8));
 115         status = AE_OK;
 116
 117 out_kfree:
 118         kfree(output.pointer);
 119         return status;
 120 }
 121
 122 static acpi_status __acpi_query_osc(u32 flags, struct acpi_osc_data *osc_data,
 123                                     u32 *result)
 124 {
 125         acpi_status status;
 126         u32 support_set;
 127         struct acpi_osc_args osc_args;
 128
 129         /* do _OSC query for all possible controls */
 130         support_set = osc_data->support_set | (flags & OSC_SUPPORT_MASKS);
 131         osc_args.capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 132         osc_args.capbuf[OSC_SUPPORT_TYPE] = support_set;
 133         osc_args.capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
 134
 135         status = acpi_run_osc(osc_data->handle, &osc_args);
 136         if (ACPI_SUCCESS(status)) {
 137                 osc_data->support_set = support_set;
 138                 *result = osc_args.ctrl_result;
 139         }
 140
 141         return status;
 142 }
 143
 144 static acpi_status acpi_query_osc(acpi_handle handle,
 145                                   u32 level, void *context, void **retval)
 146 {
 147         acpi_status status;
 148         struct acpi_osc_data *osc_data;
 149         u32 flags = (unsigned long)context, dummy;
 150         acpi_handle tmp;
 151
 152         status = acpi_get_handle(handle, "_OSC", &tmp);
 153         if (ACPI_FAILURE(status))
 154                 return AE_OK;
 155
 156         mutex_lock(&pci_acpi_lock);
 157         osc_data = acpi_get_osc_data(handle);
 158         if (!osc_data) {
 159                 printk(KERN_ERR "acpi osc data array is full\n");
 160                 goto out;
 161         }
 162
 163         __acpi_query_osc(flags, osc_data, &dummy);
 164 out:
 165         mutex_unlock(&pci_acpi_lock);
 166         return AE_OK;
 167 }
 168
 169 /**
 170  * __pci_osc_support_set - register OS support to Firmware
 171  * @flags: OS support bits
 172  * @hid: hardware ID
 173  *
 174  * Update OS support fields and doing a _OSC Query to obtain an update
 175  * from Firmware on supported control bits.
 176  **/
 177 acpi_status __pci_osc_support_set(u32 flags, const char *hid)
 178 {
 179         if (!(flags & OSC_SUPPORT_MASKS))
 180                 return AE_TYPE;
 181
 182         acpi_get_devices(hid, acpi_query_osc,
 183                          (void *)(unsigned long)flags, NULL);
 184         return AE_OK;
 185 }
 186
 187 /**
 188  * pci_osc_control_set - commit requested control to Firmware
 189  * @handle: acpi_handle for the target ACPI object
 190  * @flags: driver's requested control bits
 191  *
 192  * Attempt to take control from Firmware on requested control bits.
 193  **/
 194 acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
 195 {
 196         acpi_status status;
 197         u32 ctrlset, control_set, result;
 198         acpi_handle tmp;
 199         struct acpi_osc_data *osc_data;
 200         struct acpi_osc_args osc_args;
 201
 202         status = acpi_get_handle(handle, "_OSC", &tmp);
 203         if (ACPI_FAILURE(status))
 204                 return status;
 205
 206         mutex_lock(&pci_acpi_lock);
 207         osc_data = acpi_get_osc_data(handle);
 208         if (!osc_data) {
 209                 printk(KERN_ERR "acpi osc data array is full\n");
 210                 status = AE_ERROR;
 211                 goto out;
 212         }
 213
 214         ctrlset = (flags & OSC_CONTROL_MASKS);
 215         if (!ctrlset) {
 216                 status = AE_TYPE;
 217                 goto out;
 218         }
 219
 220         status = __acpi_query_osc(osc_data->support_set, osc_data, &result);
 221         if (ACPI_FAILURE(status))
 222                 goto out;
 223
 224         if ((result & ctrlset) != ctrlset) {
 225                 status = AE_SUPPORT;
 226                 goto out;
 227         }
 228
 229         control_set = osc_data->control_set | ctrlset;
 230         osc_args.capbuf[OSC_QUERY_TYPE] = 0;
 231         osc_args.capbuf[OSC_SUPPORT_TYPE] = osc_data->support_set;
 232         osc_args.capbuf[OSC_CONTROL_TYPE] = control_set;
 233         status = acpi_run_osc(handle, &osc_args);
 234         if (ACPI_SUCCESS(status))
 235                 osc_data->control_set = control_set;
 236 out:
 237         mutex_unlock(&pci_acpi_lock);
 238         return status;
 239 }
 240 EXPORT_SYMBOL(pci_osc_control_set);
 241
 242 /*
 243  * _SxD returns the D-state with the highest power
 244  * (lowest D-state number) supported in the S-state "x".
 245  *
 246  * If the devices does not have a _PRW
 247  * (Power Resources for Wake) supporting system wakeup from "x"
 248  * then the OS is free to choose a lower power (higher number
 249  * D-state) than the return value from _SxD.
 250  *
 251  * But if _PRW is enabled at S-state "x", the OS
 252  * must not choose a power lower than _SxD --
 253  * unless the device has an _SxW method specifying
 254  * the lowest power (highest D-state number) the device
 255  * may enter while still able to wake the system.
 256  *
 257  * ie. depending on global OS policy:
 258  *
 259  * if (_PRW at S-state x)
 260  *      choose from highest power _SxD to lowest power _SxW
 261  * else // no _PRW at S-state x
 262  *      choose highest power _SxD or any lower power
 263  */
 264
 265 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
 266 {
 267         int acpi_state;
 268
 269         acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL);
 270         if (acpi_state < 0)
 271                 return PCI_POWER_ERROR;
 272
 273         switch (acpi_state) {
 274         case ACPI_STATE_D0:
 275                 return PCI_D0;
 276         case ACPI_STATE_D1:
 277                 return PCI_D1;
 278         case ACPI_STATE_D2:
 279                 return PCI_D2;
 280         case ACPI_STATE_D3:
 281                 return PCI_D3hot;
 282         }
 283         return PCI_POWER_ERROR;
 284 }
 285
 286 static bool acpi_pci_power_manageable(struct pci_dev *dev)
 287 {
 288         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 289
 290         return handle ? acpi_bus_power_manageable(handle) : false;
 291 }
 292
 293 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 294 {
 295         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 296         acpi_handle tmp;
 297         static const u8 state_conv[] = {
 298                 [PCI_D0] = ACPI_STATE_D0,
 299                 [PCI_D1] = ACPI_STATE_D1,
 300                 [PCI_D2] = ACPI_STATE_D2,
 301                 [PCI_D3hot] = ACPI_STATE_D3,
 302                 [PCI_D3cold] = ACPI_STATE_D3
 303         };
 304         int error = -EINVAL;
 305
 306         /* If the ACPI device has _EJ0, ignore the device */
 307         if (!handle || ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0", &tmp)))
 308                 return -ENODEV;
 309
 310         switch (state) {
 311         case PCI_D0:
 312         case PCI_D1:
 313         case PCI_D2:
 314         case PCI_D3hot:
 315         case PCI_D3cold:
 316                 error = acpi_bus_set_power(handle, state_conv[state]);
 317         }
 318
 319         if (!error)
 320                 dev_printk(KERN_INFO, &dev->dev,
 321                                 "power state changed by ACPI to D%d\n", state);
 322
 323         return error;
 324 }
 325
 326 static bool acpi_pci_can_wakeup(struct pci_dev *dev)
 327 {
 328         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 329
 330         return handle ? acpi_bus_can_wakeup(handle) : false;
 331 }
 332
 333 static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
 334 {
 335         int error = acpi_pm_device_sleep_wake(&dev->dev, enable);
 336
 337         if (!error)
 338                 dev_printk(KERN_INFO, &dev->dev,
 339                                 "wake-up capability %s by ACPI\n",
 340                                 enable ? "enabled" : "disabled");
 341         return error;
 342 }
 343
 344 static struct pci_platform_pm_ops acpi_pci_platform_pm = {
 345         .is_manageable = acpi_pci_power_manageable,
 346         .set_state = acpi_pci_set_power_state,
 347         .choose_state = acpi_pci_choose_state,
 348         .can_wakeup = acpi_pci_can_wakeup,
 349         .sleep_wake = acpi_pci_sleep_wake,
 350 };
 351
 352 /* ACPI bus type */
 353 static int acpi_pci_find_device(struct device *dev, acpi_handle *handle)
 354 {
 355         struct pci_dev * pci_dev;
 356         acpi_integer    addr;
 357
 358         pci_dev = to_pci_dev(dev);
 359         /* Please ref to ACPI spec for the syntax of _ADR */
 360         addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
 361         *handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev->parent), addr);
 362         if (!*handle)
 363                 return -ENODEV;
 364         return 0;
 365 }
 366
 367 static int acpi_pci_find_root_bridge(struct device *dev, acpi_handle *handle)
 368 {
 369         int num;
 370         unsigned int seg, bus;
 371
 372         /*
 373          * The string should be the same as root bridge's name
 374          * Please look at 'pci_scan_bus_parented'
 375          */
 376         num = sscanf(dev->bus_id, "pci%04x:%02x", &seg, &bus);
 377         if (num != 2)
 378                 return -ENODEV;
 379         *handle = acpi_get_pci_rootbridge_handle(seg, bus);
 380         if (!*handle)
 381                 return -ENODEV;
 382         return 0;
 383 }
 384
 385 static struct acpi_bus_type acpi_pci_bus = {
 386         .bus = &pci_bus_type,
 387         .find_device = acpi_pci_find_device,
 388         .find_bridge = acpi_pci_find_root_bridge,
 389 };
 390
 391 static int __init acpi_pci_init(void)
 392 {
 393         int ret;
 394
 395         if (acpi_gbl_FADT.boot_flags & BAF_MSI_NOT_SUPPORTED) {
 396                 printk(KERN_INFO"ACPI FADT declares the system doesn't support MSI, so disable it\n");
 397                 pci_no_msi();
 398         }
 399
 400         if (acpi_gbl_FADT.boot_flags & BAF_PCIE_ASPM_CONTROL) {
 401                 printk(KERN_INFO"ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
 402                 pcie_no_aspm();
 403         }
 404
 405         ret = register_acpi_bus_type(&acpi_pci_bus);
 406         if (ret)
 407                 return 0;
 408         pci_set_platform_pm(&acpi_pci_platform_pm);
 409         return 0;
 410 }
 411 arch_initcall(acpi_pci_init);