drivers/pci/pcie/portdrv_pci.c

   1 /*
   2  * File:        portdrv_pci.c
   3  * Purpose:     PCI Express Port Bus Driver
   4  * Author:      Tom Nguyen <tom.l.nguyen@intel.com>
   5  * Version:     v1.0
   6  *
   7  * Copyright (C) 2004 Intel
   8  * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
   9  */
  10
  11 #include <linux/pci.h>
  12 #include <linux/kernel.h>
  13 #include <linux/errno.h>
  14 #include <linux/pm.h>
  15 #include <linux/pm_runtime.h>
  16 #include <linux/init.h>
  17 #include <linux/pcieport_if.h>
  18 #include <linux/aer.h>
  19 #include <linux/dmi.h>
  20 #include <linux/pci-aspm.h>
  21
  22 #include "portdrv.h"
  23 #include "aer/aerdrv.h"
  24
  25 /* If this switch is set, PCIe port native services should not be enabled. */
  26 bool pcie_ports_disabled;
  27
  28 /*
  29  * If this switch is set, ACPI _OSC will be used to determine whether or not to
  30  * enable PCIe port native services.
  31  */
  32 bool pcie_ports_auto = true;
  33
  34 static int __init pcie_port_setup(char *str)
  35 {
  36         if (!strncmp(str, "compat", 6)) {
  37                 pcie_ports_disabled = true;
  38         } else if (!strncmp(str, "native", 6)) {
  39                 pcie_ports_disabled = false;
  40                 pcie_ports_auto = false;
  41         } else if (!strncmp(str, "auto", 4)) {
  42                 pcie_ports_disabled = false;
  43                 pcie_ports_auto = true;
  44         }
  45
  46         return 1;
  47 }
  48 __setup("pcie_ports=", pcie_port_setup);
  49
  50 /* global data */
  51
  52 /**
  53  * pcie_clear_root_pme_status - Clear root port PME interrupt status.
  54  * @dev: PCIe root port or event collector.
  55  */
  56 void pcie_clear_root_pme_status(struct pci_dev *dev)
  57 {
  58         pcie_capability_set_dword(dev, PCI_EXP_RTSTA, PCI_EXP_RTSTA_PME);
  59 }
  60
  61 static int pcie_portdrv_restore_config(struct pci_dev *dev)
  62 {
  63         int retval;
  64
  65         retval = pci_enable_device(dev);
  66         if (retval)
  67                 return retval;
  68         pci_set_master(dev);
  69         return 0;
  70 }
  71
  72 #ifdef CONFIG_PM
  73 static int pcie_port_resume_noirq(struct device *dev)
  74 {
  75         struct pci_dev *pdev = to_pci_dev(dev);
  76
  77         /*
  78          * Some BIOSes forget to clear Root PME Status bits after system wakeup
  79          * which breaks ACPI-based runtime wakeup on PCI Express, so clear those
  80          * bits now just in case (shouldn't hurt).
  81          */
  82         if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
  83                 pcie_clear_root_pme_status(pdev);
  84         return 0;
  85 }
  86
  87 static int pcie_port_runtime_suspend(struct device *dev)
  88 {
  89         return to_pci_dev(dev)->bridge_d3 ? 0 : -EBUSY;
  90 }
  91
  92 static int pcie_port_runtime_resume(struct device *dev)
  93 {
  94         return 0;
  95 }
  96
  97 static int pcie_port_runtime_idle(struct device *dev)
  98 {
  99         /*
 100          * Assume the PCI core has set bridge_d3 whenever it thinks the port
 101          * should be good to go to D3.  Everything else, including moving
 102          * the port to D3, is handled by the PCI core.
 103          */
 104         return to_pci_dev(dev)->bridge_d3 ? 0 : -EBUSY;
 105 }
 106
 107 static const struct dev_pm_ops pcie_portdrv_pm_ops = {
 108         .suspend        = pcie_port_device_suspend,
 109         .resume         = pcie_port_device_resume,
 110         .freeze         = pcie_port_device_suspend,
 111         .thaw           = pcie_port_device_resume,
 112         .poweroff       = pcie_port_device_suspend,
 113         .restore        = pcie_port_device_resume,
 114         .resume_noirq   = pcie_port_resume_noirq,
 115         .runtime_suspend = pcie_port_runtime_suspend,
 116         .runtime_resume = pcie_port_runtime_resume,
 117         .runtime_idle   = pcie_port_runtime_idle,
 118 };
 119
 120 #define PCIE_PORTDRV_PM_OPS     (&pcie_portdrv_pm_ops)
 121
 122 #else /* !PM */
 123
 124 #define PCIE_PORTDRV_PM_OPS     NULL
 125 #endif /* !PM */
 126
 127 /*
 128  * pcie_portdrv_probe - Probe PCI-Express port devices
 129  * @dev: PCI-Express port device being probed
 130  *
 131  * If detected invokes the pcie_port_device_register() method for
 132  * this port device.
 133  *
 134  */
 135 static int pcie_portdrv_probe(struct pci_dev *dev,
 136                                         const struct pci_device_id *id)
 137 {
 138         int status;
 139
 140         if (!pci_is_pcie(dev) ||
 141             ((pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) &&
 142              (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM) &&
 143              (pci_pcie_type(dev) != PCI_EXP_TYPE_DOWNSTREAM)))
 144                 return -ENODEV;
 145
 146         status = pcie_port_device_register(dev);
 147         if (status)
 148                 return status;
 149
 150         pci_save_state(dev);
 151
 152         /*
 153          * Prevent runtime PM if the port is advertising support for PCIe
 154          * hotplug.  Otherwise the BIOS hotplug SMI code might not be able
 155          * to enumerate devices behind this port properly (the port is
 156          * powered down preventing all config space accesses to the
 157          * subordinate devices).  We can't be sure for native PCIe hotplug
 158          * either so prevent that as well.
 159          */
 160         if (!dev->is_hotplug_bridge) {
 161                 /*
 162                  * Keep the port resumed 100ms to make sure things like
 163                  * config space accesses from userspace (lspci) will not
 164                  * cause the port to repeatedly suspend and resume.
 165                  */
 166                 pm_runtime_set_autosuspend_delay(&dev->dev, 100);
 167                 pm_runtime_use_autosuspend(&dev->dev);
 168                 pm_runtime_mark_last_busy(&dev->dev);
 169                 pm_runtime_put_autosuspend(&dev->dev);
 170                 pm_runtime_allow(&dev->dev);
 171         }
 172
 173         return 0;
 174 }
 175
 176 static void pcie_portdrv_remove(struct pci_dev *dev)
 177 {
 178         if (!dev->is_hotplug_bridge) {
 179                 pm_runtime_forbid(&dev->dev);
 180                 pm_runtime_get_noresume(&dev->dev);
 181                 pm_runtime_dont_use_autosuspend(&dev->dev);
 182         }
 183
 184         pcie_port_device_remove(dev);
 185 }
 186
 187 static int error_detected_iter(struct device *device, void *data)
 188 {
 189         struct pcie_device *pcie_device;
 190         struct pcie_port_service_driver *driver;
 191         struct aer_broadcast_data *result_data;
 192         pci_ers_result_t status;
 193
 194         result_data = (struct aer_broadcast_data *) data;
 195
 196         if (device->bus == &pcie_port_bus_type && device->driver) {
 197                 driver = to_service_driver(device->driver);
 198                 if (!driver ||
 199                         !driver->err_handler ||
 200                         !driver->err_handler->error_detected)
 201                         return 0;
 202
 203                 pcie_device = to_pcie_device(device);
 204
 205                 /* Forward error detected message to service drivers */
 206                 status = driver->err_handler->error_detected(
 207                         pcie_device->port,
 208                         result_data->state);
 209                 result_data->result =
 210                         merge_result(result_data->result, status);
 211         }
 212
 213         return 0;
 214 }
 215
 216 static pci_ers_result_t pcie_portdrv_error_detected(struct pci_dev *dev,
 217                                         enum pci_channel_state error)
 218 {
 219         struct aer_broadcast_data data = {error, PCI_ERS_RESULT_CAN_RECOVER};
 220
 221         /* get true return value from &data */
 222         device_for_each_child(&dev->dev, &data, error_detected_iter);
 223         return data.result;
 224 }
 225
 226 static int mmio_enabled_iter(struct device *device, void *data)
 227 {
 228         struct pcie_device *pcie_device;
 229         struct pcie_port_service_driver *driver;
 230         pci_ers_result_t status, *result;
 231
 232         result = (pci_ers_result_t *) data;
 233
 234         if (device->bus == &pcie_port_bus_type && device->driver) {
 235                 driver = to_service_driver(device->driver);
 236                 if (driver &&
 237                         driver->err_handler &&
 238                         driver->err_handler->mmio_enabled) {
 239                         pcie_device = to_pcie_device(device);
 240
 241                         /* Forward error message to service drivers */
 242                         status = driver->err_handler->mmio_enabled(
 243                                         pcie_device->port);
 244                         *result = merge_result(*result, status);
 245                 }
 246         }
 247
 248         return 0;
 249 }
 250
 251 static pci_ers_result_t pcie_portdrv_mmio_enabled(struct pci_dev *dev)
 252 {
 253         pci_ers_result_t status = PCI_ERS_RESULT_RECOVERED;
 254
 255         /* get true return value from &status */
 256         device_for_each_child(&dev->dev, &status, mmio_enabled_iter);
 257         return status;
 258 }
 259
 260 static int slot_reset_iter(struct device *device, void *data)
 261 {
 262         struct pcie_device *pcie_device;
 263         struct pcie_port_service_driver *driver;
 264         pci_ers_result_t status, *result;
 265
 266         result = (pci_ers_result_t *) data;
 267
 268         if (device->bus == &pcie_port_bus_type && device->driver) {
 269                 driver = to_service_driver(device->driver);
 270                 if (driver &&
 271                         driver->err_handler &&
 272                         driver->err_handler->slot_reset) {
 273                         pcie_device = to_pcie_device(device);
 274
 275                         /* Forward error message to service drivers */
 276                         status = driver->err_handler->slot_reset(
 277                                         pcie_device->port);
 278                         *result = merge_result(*result, status);
 279                 }
 280         }
 281
 282         return 0;
 283 }
 284
 285 static pci_ers_result_t pcie_portdrv_slot_reset(struct pci_dev *dev)
 286 {
 287         pci_ers_result_t status = PCI_ERS_RESULT_RECOVERED;
 288
 289         /* If fatal, restore cfg space for possible link reset at upstream */
 290         if (dev->error_state == pci_channel_io_frozen) {
 291                 dev->state_saved = true;
 292                 pci_restore_state(dev);
 293                 pcie_portdrv_restore_config(dev);
 294                 pci_enable_pcie_error_reporting(dev);
 295         }
 296
 297         /* get true return value from &status */
 298         device_for_each_child(&dev->dev, &status, slot_reset_iter);
 299         return status;
 300 }
 301
 302 static int resume_iter(struct device *device, void *data)
 303 {
 304         struct pcie_device *pcie_device;
 305         struct pcie_port_service_driver *driver;
 306
 307         if (device->bus == &pcie_port_bus_type && device->driver) {
 308                 driver = to_service_driver(device->driver);
 309                 if (driver &&
 310                         driver->err_handler &&
 311                         driver->err_handler->resume) {
 312                         pcie_device = to_pcie_device(device);
 313
 314                         /* Forward error message to service drivers */
 315                         driver->err_handler->resume(pcie_device->port);
 316                 }
 317         }
 318
 319         return 0;
 320 }
 321
 322 static void pcie_portdrv_err_resume(struct pci_dev *dev)
 323 {
 324         device_for_each_child(&dev->dev, NULL, resume_iter);
 325 }
 326
 327 /*
 328  * LINUX Device Driver Model
 329  */
 330 static const struct pci_device_id port_pci_ids[] = { {
 331         /* handle any PCI-Express port */
 332         PCI_DEVICE_CLASS(((PCI_CLASS_BRIDGE_PCI << 8) | 0x00), ~0),
 333         }, { /* end: all zeroes */ }
 334 };
 335
 336 static const struct pci_error_handlers pcie_portdrv_err_handler = {
 337         .error_detected = pcie_portdrv_error_detected,
 338         .mmio_enabled = pcie_portdrv_mmio_enabled,
 339         .slot_reset = pcie_portdrv_slot_reset,
 340         .resume = pcie_portdrv_err_resume,
 341 };
 342
 343 static struct pci_driver pcie_portdriver = {
 344         .name           = "pcieport",
 345         .id_table       = &port_pci_ids[0],
 346
 347         .probe          = pcie_portdrv_probe,
 348         .remove         = pcie_portdrv_remove,
 349
 350         .err_handler    = &pcie_portdrv_err_handler,
 351
 352         .driver.pm      = PCIE_PORTDRV_PM_OPS,
 353 };
 354
 355 static int __init dmi_pcie_pme_disable_msi(const struct dmi_system_id *d)
 356 {
 357         pr_notice("%s detected: will not use MSI for PCIe PME signaling\n",
 358                   d->ident);
 359         pcie_pme_disable_msi();
 360         return 0;
 361 }
 362
 363 static struct dmi_system_id __initdata pcie_portdrv_dmi_table[] = {
 364         /*
 365          * Boxes that should not use MSI for PCIe PME signaling.
 366          */
 367         {
 368          .callback = dmi_pcie_pme_disable_msi,
 369          .ident = "MSI Wind U-100",
 370          .matches = {
 371                      DMI_MATCH(DMI_SYS_VENDOR,
 372                                 "MICRO-STAR INTERNATIONAL CO., LTD"),
 373                      DMI_MATCH(DMI_PRODUCT_NAME, "U-100"),
 374                      },
 375          },
 376          {}
 377 };
 378
 379 static int __init pcie_portdrv_init(void)
 380 {
 381         int retval;
 382
 383         if (pcie_ports_disabled)
 384                 return pci_register_driver(&pcie_portdriver);
 385
 386         dmi_check_system(pcie_portdrv_dmi_table);
 387
 388         retval = pcie_port_bus_register();
 389         if (retval) {
 390                 printk(KERN_WARNING "PCIE: bus_register error: %d\n", retval);
 391                 goto out;
 392         }
 393         retval = pci_register_driver(&pcie_portdriver);
 394         if (retval)
 395                 pcie_port_bus_unregister();
 396  out:
 397         return retval;
 398 }
 399 device_initcall(pcie_portdrv_init);