From c11daf6a8fcc42d540ad6d7bb06a6a203de908b3 Mon Sep 17 00:00:00 2001 From: Corey Minyard Date: Tue, 25 Oct 2016 20:31:53 -0500 Subject: [PATCH] ipmi: Update documentation The documentation has some information that was old and needed some things added that are new. Signed-off-by: Corey Minyard --- Documentation/IPMI.txt | 57 ++++++++++++++++++++++++------------------ 1 file changed, 32 insertions(+), 25 deletions(-) diff --git a/Documentation/IPMI.txt b/Documentation/IPMI.txt index c0d8788e75d3..72292308d0f5 100644 --- a/Documentation/IPMI.txt +++ b/Documentation/IPMI.txt @@ -111,6 +111,8 @@ ipmi_ssif - A driver for accessing BMCs on the SMBus. It uses the I2C kernel driver's SMBus interfaces to send and receive IPMI messages over the SMBus. +ipmi_powernv - A driver for access BMCs on POWERNV systems. + ipmi_watchdog - IPMI requires systems to have a very capable watchdog timer. This driver implements the standard Linux watchdog timer interface on top of the IPMI message handler. @@ -118,17 +120,15 @@ interface on top of the IPMI message handler. ipmi_poweroff - Some systems support the ability to be turned off via IPMI commands. -These are all individually selectable via configuration options. +bt-bmc - This is not part of the main driver, but instead a driver for +accessing a BMC-side interface of a BT interface. It is used on BMCs +running Linux to provide an interface to the host. -Note that the KCS-only interface has been removed. The af_ipmi driver -is no longer supported and has been removed because it was impossible -to do 32 bit emulation on 64-bit kernels with it. +These are all individually selectable via configuration options. Much documentation for the interface is in the include files. The IPMI include files are: -net/af_ipmi.h - Contains the socket interface. - linux/ipmi.h - Contains the user interface and IOCTL interface for IPMI. linux/ipmi_smi.h - Contains the interface for system management interfaces @@ -245,6 +245,16 @@ addressed (because some boards actually have multiple BMCs on them) and the user should not have to care what type of SMI is below them. +Watching For Interfaces + +When your code comes up, the IPMI driver may or may not have detected +if IPMI devices exist. So you might have to defer your setup until +the device is detected, or you might be able to do it immediately. +To handle this, and to allow for discovery, you register an SMI +watcher with ipmi_smi_watcher_register() to iterate over interfaces +and tell you when they come and go. + + Creating the User To user the message handler, you must first create a user using @@ -263,7 +273,7 @@ closing the device automatically destroys the user. Messaging -To send a message from kernel-land, the ipmi_request() call does +To send a message from kernel-land, the ipmi_request_settime() call does pretty much all message handling. Most of the parameter are self-explanatory. However, it takes a "msgid" parameter. This is NOT the sequence number of messages. It is simply a long value that is @@ -352,11 +362,12 @@ that for more details. The SI Driver ------------- -The SI driver allows up to 4 KCS or SMIC interfaces to be configured -in the system. By default, scan the ACPI tables for interfaces, and -if it doesn't find any the driver will attempt to register one KCS -interface at the spec-specified I/O port 0xca2 without interrupts. -You can change this at module load time (for a module) with: +The SI driver allows KCS, BT, and SMIC interfaces to be configured +in the system. It discovers interfaces through a host of different +methods, depending on the system. + +You can specify up to four interfaces on the module load line and +control some module parameters: modprobe ipmi_si.o type=,.... ports=,... addrs=,... @@ -367,7 +378,7 @@ You can change this at module load time (for a module) with: force_kipmid=,,... kipmid_max_busy_us=,,... unload_when_empty=[0|1] - trydefaults=[0|1] trydmi=[0|1] tryacpi=[0|1] + trydmi=[0|1] tryacpi=[0|1] tryplatform=[0|1] trypci=[0|1] Each of these except try... items is a list, the first item for the @@ -386,10 +397,6 @@ use the I/O port given as the device address. If you specify irqs as non-zero for an interface, the driver will attempt to use the given interrupt for the device. -trydefaults sets whether the standard IPMI interface at 0xca2 and -any interfaces specified by ACPE are tried. By default, the driver -tries it, set this value to zero to turn this off. - The other try... items disable discovery by their corresponding names. These are all enabled by default, set them to zero to disable them. The tryplatform disables openfirmware. @@ -434,7 +441,7 @@ kernel command line as: ipmi_si.type=,... ipmi_si.ports=,... ipmi_si.addrs=,... - ipmi_si.irqs=,... ipmi_si.trydefaults=[0|1] + ipmi_si.irqs=,... ipmi_si.regspacings=,,... ipmi_si.regsizes=,,... ipmi_si.regshifts=,,... @@ -444,11 +451,6 @@ kernel command line as: It works the same as the module parameters of the same names. -By default, the driver will attempt to detect any device specified by -ACPI, and if none of those then a KCS device at the spec-specified -0xca2. If you want to turn this off, set the "trydefaults" option to -false. - If your IPMI interface does not support interrupts and is a KCS or SMIC interface, the IPMI driver will start a kernel thread for the interface to help speed things up. This is a low-priority kernel @@ -500,7 +502,8 @@ at module load time (for a module) with: addr=[,[,...]] adapter=[,[...]] dbg=,... - slave_addrs=,,... + slave_addrs=,,... + tryacpi=[0|1] trydmi=[0|1] [dbg_probe=1] The addresses are normal I2C addresses. The adapter is the string @@ -513,6 +516,9 @@ spaces in kernel parameters. The debug flags are bit flags for each BMC found, they are: IPMI messages: 1, driver state: 2, timing: 4, I2C probe: 8 +The tryxxx parameters can be used to disable detecting interfaces +from various sources. + Setting dbg_probe to 1 will enable debugging of the probing and detection process for BMCs on the SMBusses. @@ -535,7 +541,8 @@ kernel command line as: ipmi_ssif.adapter=[,[...]] ipmi_ssif.dbg=[,[...]] ipmi_ssif.dbg_probe=1 - ipmi_ssif.slave_addrs=[,[...]] + ipmi_ssif.slave_addrs=[,[...]] + ipmi_ssif.tryacpi=[0|1] ipmi_ssif.trydmi=[0|1] These are the same options as on the module command line. -- 2.20.1