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