Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | S/390 common I/O-Layer - command line parameters and /proc entries |
| 2 | ================================================================== |
| 3 | |
| 4 | Command line parameters |
| 5 | ----------------------- |
| 6 | |
| 7 | * cio_msg = yes | no |
| 8 | |
| 9 | Determines whether information on found devices and sensed device |
| 10 | characteristics should be shown during startup, i. e. messages of the types |
| 11 | "Detected device 0.0.4711 on subchannel 0.0.0042" and "SenseID: Device |
| 12 | 0.0.4711 reports: ...". |
| 13 | |
| 14 | Default is off. |
| 15 | |
| 16 | |
| 17 | * cio_ignore = {all} | |
| 18 | {<device> | <range of devices>} | |
| 19 | {!<device> | !<range of devices>} |
| 20 | |
| 21 | The given devices will be ignored by the common I/O-layer; no detection |
| 22 | and device sensing will be done on any of those devices. The subchannel to |
| 23 | which the device in question is attached will be treated as if no device was |
| 24 | attached. |
| 25 | |
| 26 | An ignored device can be un-ignored later; see the "/proc entries"-section for |
| 27 | details. |
| 28 | |
| 29 | The devices must be given either as bus ids (0.0.abcd) or as hexadecimal |
| 30 | device numbers (0xabcd or abcd, for 2.4 backward compatibility). |
| 31 | You can use the 'all' keyword to ignore all devices. |
| 32 | The '!' operator will cause the I/O-layer to _not_ ignore a device. |
Cornelia Huck | 6fd6e4a | 2005-06-21 17:16:27 -0700 | [diff] [blame] | 33 | The command line is parsed from left to right. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
| 35 | For example, |
| 36 | cio_ignore=0.0.0023-0.0.0042,0.0.4711 |
| 37 | will ignore all devices ranging from 0.0.0023 to 0.0.0042 and the device |
| 38 | 0.0.4711, if detected. |
| 39 | As another example, |
| 40 | cio_ignore=all,!0.0.4711,!0.0.fd00-0.0.fd02 |
| 41 | will ignore all devices but 0.0.4711, 0.0.fd00, 0.0.fd01, 0.0.fd02. |
| 42 | |
| 43 | By default, no devices are ignored. |
| 44 | |
| 45 | |
| 46 | /proc entries |
| 47 | ------------- |
| 48 | |
| 49 | * /proc/cio_ignore |
| 50 | |
| 51 | Lists the ranges of devices (by bus id) which are ignored by common I/O. |
| 52 | |
| 53 | You can un-ignore certain or all devices by piping to /proc/cio_ignore. |
| 54 | "free all" will un-ignore all ignored devices, |
| 55 | "free <device range>, <device range>, ..." will un-ignore the specified |
| 56 | devices. |
| 57 | |
| 58 | For example, if devices 0.0.0023 to 0.0.0042 and 0.0.4711 are ignored, |
| 59 | - echo free 0.0.0030-0.0.0032 > /proc/cio_ignore |
| 60 | will un-ignore devices 0.0.0030 to 0.0.0032 and will leave devices 0.0.0023 |
| 61 | to 0.0.002f, 0.0.0033 to 0.0.0042 and 0.0.4711 ignored; |
| 62 | - echo free 0.0.0041 > /proc/cio_ignore will furthermore un-ignore device |
| 63 | 0.0.0041; |
| 64 | - echo free all > /proc/cio_ignore will un-ignore all remaining ignored |
| 65 | devices. |
| 66 | |
| 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 |
Cornelia Huck | 9b10fe5 | 2006-10-18 18:30:55 +0200 | [diff] [blame] | 69 | available to the system. Note that un-ignoring is performed asynchronously. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | |
| 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 |
| 73 | specified devices. |
| 74 | |
Cornelia Huck | 6fd6e4a | 2005-06-21 17:16:27 -0700 | [diff] [blame] | 75 | Note: While already known devices can be added to the list of devices to be |
| 76 | ignored, there will be no effect on then. However, if such a device |
Nicolas Kaiser | 2254f5a | 2006-12-04 15:40:23 +0100 | [diff] [blame] | 77 | disappears and then reappears, it will then be ignored. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | |
Cornelia Huck | 6fd6e4a | 2005-06-21 17:16:27 -0700 | [diff] [blame] | 79 | For example, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | "echo add 0.0.a000-0.0.accc, 0.0.af00-0.0.afff > /proc/cio_ignore" |
Cornelia Huck | 6fd6e4a | 2005-06-21 17:16:27 -0700 | [diff] [blame] | 81 | will add 0.0.a000-0.0.accc and 0.0.af00-0.0.afff to the list of ignored |
| 82 | devices. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | |
| 84 | The devices can be specified either by bus id (0.0.abcd) or, for 2.4 backward |
Nicolas Kaiser | 2254f5a | 2006-12-04 15:40:23 +0100 | [diff] [blame] | 85 | compatibility, by the device number in hexadecimal (0xabcd or abcd). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | |
| 87 | |
| 88 | * /proc/s390dbf/cio_*/ (S/390 debug feature) |
| 89 | |
| 90 | Some views generated by the debug feature to hold various debug outputs. |
| 91 | |
| 92 | - /proc/s390dbf/cio_crw/sprintf |
| 93 | Messages from the processing of pending channel report words (machine check |
| 94 | handling), which will also show when CONFIG_DEBUG_CRW is defined. |
| 95 | |
| 96 | - /proc/s390dbf/cio_msg/sprintf |
| 97 | Various debug messages from the common I/O-layer; generally, messages which |
| 98 | will also show when CONFIG_DEBUG_IO is defined. |
| 99 | |
| 100 | - /proc/s390dbf/cio_trace/hex_ascii |
| 101 | Logs the calling of functions in the common I/O-layer and, if applicable, |
Cornelia Huck | 6fd6e4a | 2005-06-21 17:16:27 -0700 | [diff] [blame] | 102 | which subchannel they were called for, as well as dumps of some data |
| 103 | structures (like irb in an error case). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | |
| 105 | The level of logging can be changed to be more or less verbose by piping to |
| 106 | /proc/s390dbf/cio_*/level a number between 0 and 6; see the documentation on |
| 107 | the S/390 debug feature (Documentation/s390/s390dbf.txt) for details. |
| 108 | |
| 109 | * For some of the information present in the /proc filesystem in 2.4 (namely, |
| 110 | /proc/subchannels and /proc/chpids), see driver-model.txt. |
| 111 | Information formerly in /proc/irq_count is now in /proc/interrupts. |