Merge tag 'fsi-for-v5.16' of git://git.kernel.org/pub/scm/linux/kerne…

…l/git/joel/fsi into char-misc-next

Joel writes:

FSI changes for v5.16

 - SBEFIFO usersapce interfaces to perform FFDC (First Failure
   Data Capture) and detect timeouts

 - A fix to handle multiple messages in flight

* tag 'fsi-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/joel/fsi:
  fsi: sbefifo: Use interruptible mutex locking
  fsi: sbefifo: Add sysfs file indicating a timeout error
  docs: ABI: testing: Document the SBEFIFO timeout interface
  hwmon: (occ) Provide the SBEFIFO FFDC in binary sysfs
  docs: ABI: testing: Document the OCC hwmon FFDC binary interface
  fsi: occ: Store the SBEFIFO FFDC in the user response buffer
  fsi: occ: Use a large buffer for responses
  hwmon: (occ) Remove sequence numbering and checksum calculation
  fsi: occ: Force sequence numbering per OCC

Documentation/ABI/testing/sysfs-bus-fsi-devices-sbefifo

@@ -0,0 +1,10 @@
+What:		/sys/bus/fsi/devices/XX.XX.00:06/sbefifoX/timeout
+KernelVersion:	5.15
+Contact:	eajames@linux.ibm.com
+Description:
+		Indicates whether or not this SBE device has experienced a
+		timeout; i.e. the SBE did not respond within the time allotted
+		by the driver. A value of 1 indicates that a timeout has
+		ocurred and no transfers have completed since the timeout. A
+		value of 0 indicates that no timeout has ocurred, or if one
+		has, more recent transfers have completed successful.

Documentation/ABI/testing/sysfs-bus-platform-devices-occ-hwmon

@@ -0,0 +1,13 @@
+What:		/sys/bus/platform/devices/occ-hwmon.X/ffdc
+KernelVersion:	5.15
+Contact:	eajames@linux.ibm.com
+Description:
+		Contains the First Failure Data Capture from the SBEFIFO
+		hardware, if there is any from a previous transfer. Otherwise,
+		the file is empty. The data is cleared when it's been
+		completely read by a user. As the name suggests, only the data
+		from the first error is saved, until it's cleared upon read. The OCC hwmon driver, running on
+		a Baseboard Management Controller (BMC), communicates with
+		POWER9 and up processors over the Self-Boot Engine (SBE) FIFO.
+		In many error conditions, the SBEFIFO will return error data
+		indicating the type of error and system state, etc.