diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/HOWTO | 20 | ||||
-rw-r--r-- | Documentation/MSI-HOWTO.txt | 63 | ||||
-rw-r--r-- | Documentation/feature-removal-schedule.txt | 2 | ||||
-rw-r--r-- | Documentation/kernel-parameters.txt | 5 | ||||
-rw-r--r-- | Documentation/s390/CommonIO | 2 | ||||
-rw-r--r-- | Documentation/s390/cds.txt | 52 | ||||
-rw-r--r-- | Documentation/s390/driver-model.txt | 3 |
7 files changed, 116 insertions, 31 deletions
diff --git a/Documentation/HOWTO b/Documentation/HOWTO index d6f3dd1a3464..8d51c148f721 100644 --- a/Documentation/HOWTO +++ b/Documentation/HOWTO | |||
@@ -395,6 +395,26 @@ bugme-janitor mailing list (every change in the bugzilla is mailed here) | |||
395 | 395 | ||
396 | 396 | ||
397 | 397 | ||
398 | Managing bug reports | ||
399 | -------------------- | ||
400 | |||
401 | One of the best ways to put into practice your hacking skills is by fixing | ||
402 | bugs reported by other people. Not only you will help to make the kernel | ||
403 | more stable, you'll learn to fix real world problems and you will improve | ||
404 | your skills, and other developers will be aware of your presence. Fixing | ||
405 | bugs is one of the best ways to get merits among other developers, because | ||
406 | not many people like wasting time fixing other people's bugs. | ||
407 | |||
408 | To work in the already reported bug reports, go to http://bugzilla.kernel.org. | ||
409 | If you want to be advised of the future bug reports, you can subscribe to the | ||
410 | bugme-new mailing list (only new bug reports are mailed here) or to the | ||
411 | bugme-janitor mailing list (every change in the bugzilla is mailed here) | ||
412 | |||
413 | http://lists.osdl.org/mailman/listinfo/bugme-new | ||
414 | http://lists.osdl.org/mailman/listinfo/bugme-janitors | ||
415 | |||
416 | |||
417 | |||
398 | Mailing lists | 418 | Mailing lists |
399 | ------------- | 419 | ------------- |
400 | 420 | ||
diff --git a/Documentation/MSI-HOWTO.txt b/Documentation/MSI-HOWTO.txt index c70306abb7b2..5c34910665d1 100644 --- a/Documentation/MSI-HOWTO.txt +++ b/Documentation/MSI-HOWTO.txt | |||
@@ -470,7 +470,68 @@ LOC: 324553 325068 | |||
470 | ERR: 0 | 470 | ERR: 0 |
471 | MIS: 0 | 471 | MIS: 0 |
472 | 472 | ||
473 | 6. FAQ | 473 | 6. MSI quirks |
474 | |||
475 | Several PCI chipsets or devices are known to not support MSI. | ||
476 | The PCI stack provides 3 possible levels of MSI disabling: | ||
477 | * on a single device | ||
478 | * on all devices behind a specific bridge | ||
479 | * globally | ||
480 | |||
481 | 6.1. Disabling MSI on a single device | ||
482 | |||
483 | Under some circumstances, it might be required to disable MSI on a | ||
484 | single device, It may be achived by either not calling pci_enable_msi() | ||
485 | or all, or setting the pci_dev->no_msi flag before (most of the time | ||
486 | in a quirk). | ||
487 | |||
488 | 6.2. Disabling MSI below a bridge | ||
489 | |||
490 | The vast majority of MSI quirks are required by PCI bridges not | ||
491 | being able to route MSI between busses. In this case, MSI have to be | ||
492 | disabled on all devices behind this bridge. It is achieves by setting | ||
493 | the PCI_BUS_FLAGS_NO_MSI flag in the pci_bus->bus_flags of the bridge | ||
494 | subordinate bus. There is no need to set the same flag on bridges that | ||
495 | are below the broken brigde. When pci_enable_msi() is called to enable | ||
496 | MSI on a device, pci_msi_supported() takes care of checking the NO_MSI | ||
497 | flag in all parent busses of the device. | ||
498 | |||
499 | Some bridges actually support dynamic MSI support enabling/disabling | ||
500 | by changing some bits in their PCI configuration space (especially | ||
501 | the Hypertransport chipsets such as the nVidia nForce and Serverworks | ||
502 | HT2000). It may then be required to update the NO_MSI flag on the | ||
503 | corresponding devices in the sysfs hierarchy. To enable MSI support | ||
504 | on device "0000:00:0e", do: | ||
505 | |||
506 | echo 1 > /sys/bus/pci/devices/0000:00:0e/msi_bus | ||
507 | |||
508 | To disable MSI support, echo 0 instead of 1. Note that it should be | ||
509 | used with caution since changing this value might break interrupts. | ||
510 | |||
511 | 6.3. Disabling MSI globally | ||
512 | |||
513 | Some extreme cases may require to disable MSI globally on the system. | ||
514 | For now, the only known case is a Serverworks PCI-X chipsets (MSI are | ||
515 | not supported on several busses that are not all connected to the | ||
516 | chipset in the Linux PCI hierarchy). In the vast majority of other | ||
517 | cases, disabling only behind a specific bridge is enough. | ||
518 | |||
519 | For debugging purpose, the user may also pass pci=nomsi on the kernel | ||
520 | command-line to explicitly disable MSI globally. But, once the appro- | ||
521 | priate quirks are added to the kernel, this option should not be | ||
522 | required anymore. | ||
523 | |||
524 | 6.4. Finding why MSI cannot be enabled on a device | ||
525 | |||
526 | Assuming that MSI are not enabled on a device, you should look at | ||
527 | dmesg to find messages that quirks may output when disabling MSI | ||
528 | on some devices, some bridges or even globally. | ||
529 | Then, lspci -t gives the list of bridges above a device. Reading | ||
530 | /sys/bus/pci/devices/0000:00:0e/msi_bus will tell you whether MSI | ||
531 | are enabled (1) or disabled (0). In 0 is found in a single bridge | ||
532 | msi_bus file above the device, MSI cannot be enabled. | ||
533 | |||
534 | 7. FAQ | ||
474 | 535 | ||
475 | Q1. Are there any limitations on using the MSI? | 536 | Q1. Are there any limitations on using the MSI? |
476 | 537 | ||
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 24f3c63b3017..1ac3c74646e3 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt | |||
@@ -255,7 +255,7 @@ Who: Stephen Hemminger <shemminger@osdl.org> | |||
255 | 255 | ||
256 | 256 | ||
257 | What: PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment | 257 | What: PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment |
258 | When: Oktober 2008 | 258 | When: October 2008 |
259 | Why: The stacking of class devices makes these values misleading and | 259 | Why: The stacking of class devices makes these values misleading and |
260 | inconsistent. | 260 | inconsistent. |
261 | Class devices should not carry any of these properties, and bus | 261 | Class devices should not carry any of these properties, and bus |
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index ff571f9298e0..dd00fd556a60 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt | |||
@@ -1231,6 +1231,11 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1231 | machine check when some devices' config space | 1231 | machine check when some devices' config space |
1232 | is read. But various workarounds are disabled | 1232 | is read. But various workarounds are disabled |
1233 | and some IOMMU drivers will not work. | 1233 | and some IOMMU drivers will not work. |
1234 | bfsort Sort PCI devices into breadth-first order. | ||
1235 | This sorting is done to get a device | ||
1236 | order compatible with older (<= 2.4) kernels. | ||
1237 | nobfsort Don't sort PCI devices into breadth-first order. | ||
1238 | |||
1234 | pcmv= [HW,PCMCIA] BadgePAD 4 | 1239 | pcmv= [HW,PCMCIA] BadgePAD 4 |
1235 | 1240 | ||
1236 | pd. [PARIDE] | 1241 | pd. [PARIDE] |
diff --git a/Documentation/s390/CommonIO b/Documentation/s390/CommonIO index 59d1166d41ee..d684a6ac69a8 100644 --- a/Documentation/s390/CommonIO +++ b/Documentation/s390/CommonIO | |||
@@ -66,7 +66,7 @@ Command line parameters | |||
66 | 66 | ||
67 | When a device is un-ignored, device recognition and sensing is performed and | 67 | When a device is un-ignored, device recognition and sensing is performed and |
68 | the device driver will be notified if possible, so the device will become | 68 | the device driver will be notified if possible, so the device will become |
69 | available to the system. | 69 | available to the system. Note that un-ignoring is performed asynchronously. |
70 | 70 | ||
71 | You can also add ranges of devices to be ignored by piping to | 71 | You can also add ranges of devices to be ignored by piping to |
72 | /proc/cio_ignore; "add <device range>, <device range>, ..." will ignore the | 72 | /proc/cio_ignore; "add <device range>, <device range>, ..." will ignore the |
diff --git a/Documentation/s390/cds.txt b/Documentation/s390/cds.txt index d80e5733827d..32a96cc39215 100644 --- a/Documentation/s390/cds.txt +++ b/Documentation/s390/cds.txt | |||
@@ -174,14 +174,10 @@ read_dev_chars() - Read Device Characteristics | |||
174 | 174 | ||
175 | This routine returns the characteristics for the device specified. | 175 | This routine returns the characteristics for the device specified. |
176 | 176 | ||
177 | The function is meant to be called with an irq handler in place; that is, | 177 | The function is meant to be called with the device already enabled; that is, |
178 | at earliest during set_online() processing. | 178 | at earliest during set_online() processing. |
179 | 179 | ||
180 | While the request is processed synchronously, the device interrupt | 180 | The ccw_device must not be locked prior to calling read_dev_chars(). |
181 | handler is called for final ending status. In case of error situations the | ||
182 | interrupt handler may recover appropriately. The device irq handler can | ||
183 | recognize the corresponding interrupts by the interruption parameter be | ||
184 | 0x00524443. The ccw_device must not be locked prior to calling read_dev_chars(). | ||
185 | 181 | ||
186 | The function may be called enabled or disabled. | 182 | The function may be called enabled or disabled. |
187 | 183 | ||
@@ -410,26 +406,7 @@ individual flag meanings. | |||
410 | 406 | ||
411 | Usage Notes : | 407 | Usage Notes : |
412 | 408 | ||
413 | Prior to call ccw_device_start() the device driver must assure disabled state, | 409 | ccw_device_start() must be called disabled and with the ccw device lock held. |
414 | i.e. the I/O mask value in the PSW must be disabled. This can be accomplished | ||
415 | by calling local_save_flags( flags). The current PSW flags are preserved and | ||
416 | can be restored by local_irq_restore( flags) at a later time. | ||
417 | |||
418 | If the device driver violates this rule while running in a uni-processor | ||
419 | environment an interrupt might be presented prior to the ccw_device_start() | ||
420 | routine returning to the device driver main path. In this case we will end in a | ||
421 | deadlock situation as the interrupt handler will try to obtain the irq | ||
422 | lock the device driver still owns (see below) ! | ||
423 | |||
424 | The driver must assure to hold the device specific lock. This can be | ||
425 | accomplished by | ||
426 | |||
427 | (i) spin_lock(get_ccwdev_lock(cdev)), or | ||
428 | (ii) spin_lock_irqsave(get_ccwdev_lock(cdev), flags) | ||
429 | |||
430 | Option (i) should be used if the calling routine is running disabled for | ||
431 | I/O interrupts (see above) already. Option (ii) obtains the device gate und | ||
432 | puts the CPU into I/O disabled state by preserving the current PSW flags. | ||
433 | 410 | ||
434 | The device driver is allowed to issue the next ccw_device_start() call from | 411 | The device driver is allowed to issue the next ccw_device_start() call from |
435 | within its interrupt handler already. It is not required to schedule a | 412 | within its interrupt handler already. It is not required to schedule a |
@@ -488,7 +465,7 @@ int ccw_device_resume(struct ccw_device *cdev); | |||
488 | 465 | ||
489 | cdev - ccw_device the resume operation is requested for | 466 | cdev - ccw_device the resume operation is requested for |
490 | 467 | ||
491 | The resume_IO() function returns: | 468 | The ccw_device_resume() function returns: |
492 | 469 | ||
493 | 0 - suspended channel program is resumed | 470 | 0 - suspended channel program is resumed |
494 | -EBUSY - status pending | 471 | -EBUSY - status pending |
@@ -507,6 +484,8 @@ a long-running channel program or the device might require to initially issue | |||
507 | a halt subchannel (HSCH) I/O command. For those purposes the ccw_device_halt() | 484 | a halt subchannel (HSCH) I/O command. For those purposes the ccw_device_halt() |
508 | command is provided. | 485 | command is provided. |
509 | 486 | ||
487 | ccw_device_halt() must be called disabled and with the ccw device lock held. | ||
488 | |||
510 | int ccw_device_halt(struct ccw_device *cdev, | 489 | int ccw_device_halt(struct ccw_device *cdev, |
511 | unsigned long intparm); | 490 | unsigned long intparm); |
512 | 491 | ||
@@ -517,7 +496,7 @@ intparm : interruption parameter; value is only used if no I/O | |||
517 | 496 | ||
518 | The ccw_device_halt() function returns : | 497 | The ccw_device_halt() function returns : |
519 | 498 | ||
520 | 0 - successful completion or request successfully initiated | 499 | 0 - request successfully initiated |
521 | -EBUSY - the device is currently busy, or status pending. | 500 | -EBUSY - the device is currently busy, or status pending. |
522 | -ENODEV - cdev invalid. | 501 | -ENODEV - cdev invalid. |
523 | -EINVAL - The device is not operational or the ccw device is not online. | 502 | -EINVAL - The device is not operational or the ccw device is not online. |
@@ -533,6 +512,23 @@ can then perform an appropriate action. Prior to interrupt of an outstanding | |||
533 | read to a network device (with or without PCI flag) a ccw_device_halt() | 512 | read to a network device (with or without PCI flag) a ccw_device_halt() |
534 | is required to end the pending operation. | 513 | is required to end the pending operation. |
535 | 514 | ||
515 | ccw_device_clear() - Terminage I/O Request Processing | ||
516 | |||
517 | In order to terminate all I/O processing at the subchannel, the clear subchannel | ||
518 | (CSCH) command is used. It can be issued via ccw_device_clear(). | ||
519 | |||
520 | ccw_device_clear() must be called disabled and with the ccw device lock held. | ||
521 | |||
522 | int ccw_device_clear(struct ccw_device *cdev, unsigned long intparm); | ||
523 | |||
524 | cdev: ccw_device the clear operation is requested for | ||
525 | intparm: interruption parameter (see ccw_device_halt()) | ||
526 | |||
527 | The ccw_device_clear() function returns: | ||
528 | |||
529 | 0 - request successfully initiated | ||
530 | -ENODEV - cdev invalid | ||
531 | -EINVAL - The device is not operational or the ccw device is not online. | ||
536 | 532 | ||
537 | Miscellaneous Support Routines | 533 | Miscellaneous Support Routines |
538 | 534 | ||
diff --git a/Documentation/s390/driver-model.txt b/Documentation/s390/driver-model.txt index 62c082387aea..77bf450ec39b 100644 --- a/Documentation/s390/driver-model.txt +++ b/Documentation/s390/driver-model.txt | |||
@@ -239,6 +239,9 @@ status - Can be 'online' or 'offline'. | |||
239 | 239 | ||
240 | type - The physical type of the channel path. | 240 | type - The physical type of the channel path. |
241 | 241 | ||
242 | shared - Whether the channel path is shared. | ||
243 | |||
244 | cmg - The channel measurement group. | ||
242 | 245 | ||
243 | 3. System devices | 246 | 3. System devices |
244 | ----------------- | 247 | ----------------- |