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         struct list_head sibiling;
  28 };
  29 static LIST_HEAD(acpi_osc_data_list);
  30
  31 struct acpi_osc_args {
  32         u32 capbuf[3];
  33         u32 ctrl_result;
  34 };
  35
  36 static DEFINE_MUTEX(pci_acpi_lock);
  37
  38 static struct acpi_osc_data *acpi_get_osc_data(acpi_handle handle)
  39 {
  40         struct acpi_osc_data *data;
  41
  42         list_for_each_entry(data, &acpi_osc_data_list, sibiling) {
  43                 if (data->handle == handle)
  44                         return data;
  45         }
  46         data = kzalloc(sizeof(*data), GFP_KERNEL);
  47         if (!data)
  48                 return NULL;
  49         INIT_LIST_HEAD(&data->sibiling);
  50         data->handle = handle;
  51         list_add_tail(&data->sibiling, &acpi_osc_data_list);
  52         return data;
  53 }
  54
  55 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
  56                           0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
  57
  58 static acpi_status acpi_run_osc(acpi_handle handle,
  59                                 struct acpi_osc_args *osc_args)
  60 {
  61         acpi_status status;
  62         struct acpi_object_list input;
  63         union acpi_object in_params[4];
  64         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
  65         union acpi_object *out_obj;
  66         u32 errors, flags = osc_args->capbuf[OSC_QUERY_TYPE];
  67
  68         /* Setting up input parameters */
  69         input.count = 4;
  70         input.pointer = in_params;
  71         in_params[0].type               = ACPI_TYPE_BUFFER;
  72         in_params[0].buffer.length      = 16;
  73         in_params[0].buffer.pointer     = OSC_UUID;
  74         in_params[1].type               = ACPI_TYPE_INTEGER;
  75         in_params[1].integer.value      = 1;
  76         in_params[2].type               = ACPI_TYPE_INTEGER;
  77         in_params[2].integer.value      = 3;
  78         in_params[3].type               = ACPI_TYPE_BUFFER;
  79         in_params[3].buffer.length      = 12;
  80         in_params[3].buffer.pointer     = (u8 *)osc_args->capbuf;
  81
  82         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
  83         if (ACPI_FAILURE(status))
  84                 return status;
  85
  86         if (!output.length)
  87                 return AE_NULL_OBJECT;
  88
  89         out_obj = output.pointer;
  90         if (out_obj->type != ACPI_TYPE_BUFFER) {
  91                 printk(KERN_DEBUG "Evaluate _OSC returns wrong type\n");
  92                 status = AE_TYPE;
  93                 goto out_kfree;
  94         }
  95         /* Need to ignore the bit0 in result code */
  96         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
  97         if (errors) {
  98                 if (errors & OSC_REQUEST_ERROR)
  99                         printk(KERN_DEBUG "_OSC request fails\n");
 100                 if (errors & OSC_INVALID_UUID_ERROR)
 101                         printk(KERN_DEBUG "_OSC invalid UUID\n");
 102                 if (errors & OSC_INVALID_REVISION_ERROR)
 103                         printk(KERN_DEBUG "_OSC invalid revision\n");
 104                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
 105                         if (flags & OSC_QUERY_ENABLE)
 106                                 goto out_success;
 107                         printk(KERN_DEBUG "_OSC FW not grant req. control\n");
 108                         status = AE_SUPPORT;
 109                         goto out_kfree;
 110                 }
 111                 status = AE_ERROR;
 112                 goto out_kfree;
 113         }
 114 out_success:
 115         osc_args->ctrl_result =
 116                 *((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                                     u32 *result)
 126 {
 127         acpi_status status;
 128         u32 support_set;
 129         struct acpi_osc_args osc_args;
 130
 131         /* do _OSC query for all possible controls */
 132         support_set = osc_data->support_set | (flags & OSC_SUPPORT_MASKS);
 133         osc_args.capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 134         osc_args.capbuf[OSC_SUPPORT_TYPE] = support_set;
 135         osc_args.capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
 136
 137         status = acpi_run_osc(osc_data->handle, &osc_args);
 138         if (ACPI_SUCCESS(status)) {
 139                 osc_data->support_set = support_set;
 140                 *result = osc_args.ctrl_result;
 141         }
 142
 143         return status;
 144 }
 145
 146 static acpi_status acpi_query_osc(acpi_handle handle,
 147                                   u32 level, void *context, void **retval)
 148 {
 149         acpi_status status;
 150         struct acpi_osc_data *osc_data;
 151         u32 flags = (unsigned long)context, dummy;
 152         acpi_handle tmp;
 153
 154         status = acpi_get_handle(handle, "_OSC", &tmp);
 155         if (ACPI_FAILURE(status))
 156                 return AE_OK;
 157
 158         mutex_lock(&pci_acpi_lock);
 159         osc_data = acpi_get_osc_data(handle);
 160         if (!osc_data) {
 161                 printk(KERN_ERR "acpi osc data array is full\n");
 162                 goto out;
 163         }
 164
 165         __acpi_query_osc(flags, osc_data, &dummy);
 166 out:
 167         mutex_unlock(&pci_acpi_lock);
 168         return AE_OK;
 169 }
 170
 171 /**
 172  * __pci_osc_support_set - register OS support to Firmware
 173  * @flags: OS support bits
 174  * @hid: hardware ID
 175  *
 176  * Update OS support fields and doing a _OSC Query to obtain an update
 177  * from Firmware on supported control bits.
 178  **/
 179 acpi_status __pci_osc_support_set(u32 flags, const char *hid)
 180 {
 181         if (!(flags & OSC_SUPPORT_MASKS))
 182                 return AE_TYPE;
 183
 184         acpi_get_devices(hid, acpi_query_osc,
 185                          (void *)(unsigned long)flags, NULL);
 186         return AE_OK;
 187 }
 188
 189 /**
 190  * pci_osc_control_set - commit requested control to Firmware
 191  * @handle: acpi_handle for the target ACPI object
 192  * @flags: driver's requested control bits
 193  *
 194  * Attempt to take control from Firmware on requested control bits.
 195  **/
 196 acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
 197 {
 198         acpi_status status;
 199         u32 ctrlset, control_set, result;
 200         acpi_handle tmp;
 201         struct acpi_osc_data *osc_data;
 202         struct acpi_osc_args osc_args;
 203
 204         status = acpi_get_handle(handle, "_OSC", &tmp);
 205         if (ACPI_FAILURE(status))
 206                 return status;
 207
 208         mutex_lock(&pci_acpi_lock);
 209         osc_data = acpi_get_osc_data(handle);
 210         if (!osc_data) {
 211                 printk(KERN_ERR "acpi osc data array is full\n");
 212                 status = AE_ERROR;
 213                 goto out;
 214         }
 215
 216         ctrlset = (flags & OSC_CONTROL_MASKS);
 217         if (!ctrlset) {
 218                 status = AE_TYPE;
 219                 goto out;
 220         }
 221
 222         status = __acpi_query_osc(osc_data->support_set, osc_data, &result);
 223         if (ACPI_FAILURE(status))
 224                 goto out;
 225
 226         if ((result & ctrlset) != ctrlset) {
 227                 status = AE_SUPPORT;
 228                 goto out;
 229         }
 230
 231         control_set = osc_data->control_set | ctrlset;
 232         osc_args.capbuf[OSC_QUERY_TYPE] = 0;
 233         osc_args.capbuf[OSC_SUPPORT_TYPE] = osc_data->support_set;
 234         osc_args.capbuf[OSC_CONTROL_TYPE] = control_set;
 235         status = acpi_run_osc(handle, &osc_args);
 236         if (ACPI_SUCCESS(status))
 237                 osc_data->control_set = control_set;
 238 out:
 239         mutex_unlock(&pci_acpi_lock);
 240         return status;
 241 }
 242 EXPORT_SYMBOL(pci_osc_control_set);
 243
 244 /*
 245  * _SxD returns the D-state with the highest power
 246  * (lowest D-state number) supported in the S-state "x".
 247  *
 248  * If the devices does not have a _PRW
 249  * (Power Resources for Wake) supporting system wakeup from "x"
 250  * then the OS is free to choose a lower power (higher number
 251  * D-state) than the return value from _SxD.
 252  *
 253  * But if _PRW is enabled at S-state "x", the OS
 254  * must not choose a power lower than _SxD --
 255  * unless the device has an _SxW method specifying
 256  * the lowest power (highest D-state number) the device
 257  * may enter while still able to wake the system.
 258  *
 259  * ie. depending on global OS policy:
 260  *
 261  * if (_PRW at S-state x)
 262  *      choose from highest power _SxD to lowest power _SxW
 263  * else // no _PRW at S-state x
 264  *      choose highest power _SxD or any lower power
 265  */
 266
 267 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
 268 {
 269         int acpi_state;
 270
 271         acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL);
 272         if (acpi_state < 0)
 273                 return PCI_POWER_ERROR;
 274
 275         switch (acpi_state) {
 276         case ACPI_STATE_D0:
 277                 return PCI_D0;
 278         case ACPI_STATE_D1:
 279                 return PCI_D1;
 280         case ACPI_STATE_D2:
 281                 return PCI_D2;
 282         case ACPI_STATE_D3:
 283                 return PCI_D3hot;
 284         }
 285         return PCI_POWER_ERROR;
 286 }
 287
 288 static bool acpi_pci_power_manageable(struct pci_dev *dev)
 289 {
 290         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 291
 292         return handle ? acpi_bus_power_manageable(handle) : false;
 293 }
 294
 295 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 296 {
 297         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 298         acpi_handle tmp;
 299         static const u8 state_conv[] = {
 300                 [PCI_D0] = ACPI_STATE_D0,
 301                 [PCI_D1] = ACPI_STATE_D1,
 302                 [PCI_D2] = ACPI_STATE_D2,
 303                 [PCI_D3hot] = ACPI_STATE_D3,
 304                 [PCI_D3cold] = ACPI_STATE_D3
 305         };
 306         int error = -EINVAL;
 307
 308         /* If the ACPI device has _EJ0, ignore the device */
 309         if (!handle || ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0", &tmp)))
 310                 return -ENODEV;
 311
 312         switch (state) {
 313         case PCI_D0:
 314         case PCI_D1:
 315         case PCI_D2:
 316         case PCI_D3hot:
 317         case PCI_D3cold:
 318                 error = acpi_bus_set_power(handle, state_conv[state]);
 319         }
 320
 321         if (!error)
 322                 dev_printk(KERN_INFO, &dev->dev,
 323                                 "power state changed by ACPI to D%d\n", state);
 324
 325         return error;
 326 }
 327
 328 static bool acpi_pci_can_wakeup(struct pci_dev *dev)
 329 {
 330         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
 331
 332         return handle ? acpi_bus_can_wakeup(handle) : false;
 333 }
 334
 335 static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
 336 {
 337         int error = acpi_pm_device_sleep_wake(&dev->dev, enable);
 338
 339         if (!error)
 340                 dev_printk(KERN_INFO, &dev->dev,
 341                                 "wake-up capability %s by ACPI\n",
 342                                 enable ? "enabled" : "disabled");
 343         return error;
 344 }
 345
 346 static struct pci_platform_pm_ops acpi_pci_platform_pm = {
 347         .is_manageable = acpi_pci_power_manageable,
 348         .set_state = acpi_pci_set_power_state,
 349         .choose_state = acpi_pci_choose_state,
 350         .can_wakeup = acpi_pci_can_wakeup,
 351         .sleep_wake = acpi_pci_sleep_wake,
 352 };
 353
 354 /* ACPI bus type */
 355 static int acpi_pci_find_device(struct device *dev, acpi_handle *handle)
 356 {
 357         struct pci_dev * pci_dev;
 358         acpi_integer    addr;
 359
 360         pci_dev = to_pci_dev(dev);
 361         /* Please ref to ACPI spec for the syntax of _ADR */
 362         addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
 363         *handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev->parent), addr);
 364         if (!*handle)
 365                 return -ENODEV;
 366         return 0;
 367 }
 368
 369 static int acpi_pci_find_root_bridge(struct device *dev, acpi_handle *handle)
 370 {
 371         int num;
 372         unsigned int seg, bus;
 373
 374         /*
 375          * The string should be the same as root bridge's name
 376          * Please look at 'pci_scan_bus_parented'
 377          */
 378         num = sscanf(dev->bus_id, "pci%04x:%02x", &seg, &bus);
 379         if (num != 2)
 380                 return -ENODEV;
 381         *handle = acpi_get_pci_rootbridge_handle(seg, bus);
 382         if (!*handle)
 383                 return -ENODEV;
 384         return 0;
 385 }
 386
 387 static struct acpi_bus_type acpi_pci_bus = {
 388         .bus = &pci_bus_type,
 389         .find_device = acpi_pci_find_device,
 390         .find_bridge = acpi_pci_find_root_bridge,
 391 };
 392
 393 static int __init acpi_pci_init(void)
 394 {
 395         int ret;
 396
 397         if (acpi_gbl_FADT.boot_flags & BAF_MSI_NOT_SUPPORTED) {
 398                 printk(KERN_INFO"ACPI FADT declares the system doesn't support MSI, so disable it\n");
 399                 pci_no_msi();
 400         }
 401
 402         if (acpi_gbl_FADT.boot_flags & BAF_PCIE_ASPM_CONTROL) {
 403                 printk(KERN_INFO"ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
 404                 pcie_no_aspm();
 405         }
 406
 407         ret = register_acpi_bus_type(&acpi_pci_bus);
 408         if (ret)
 409                 return 0;
 410         pci_set_platform_pm(&acpi_pci_platform_pm);
 411         return 0;
 412 }
 413 arch_initcall(acpi_pci_init);