[RFC v9 2/5] dt-bindings: pstore-block: new support for blkoops

From: liaoweixiong
Date: Tue Feb 19 2019 - 06:53:38 EST

Create DT binding document for blkoops.

Signed-off-by: liaoweixiong <liaoweixiong@xxxxxxxxxxxxxxxxx>
.../devicetree/bindings/pstore/blkoops.txt | 53 ++++++++++++++++++++++
2 files changed, 54 insertions(+)
create mode 100644 Documentation/devicetree/bindings/pstore/blkoops.txt

diff --git a/Documentation/devicetree/bindings/pstore/blkoops.txt b/Documentation/devicetree/bindings/pstore/blkoops.txt
new file mode 100644
index 0000000..5462915
--- /dev/null
+++ b/Documentation/devicetree/bindings/pstore/blkoops.txt
@@ -0,0 +1,53 @@
+Blkoops oops logger
+Blkoops provides a block partition for oops, excluding panics now, so they can
+be recovered after a reboot.
+Any space of block device will be used for a circular buffer of oops records.
+These records have a configurable size, with a size of 0 indicating that they
+should be disabled.
+At least one of "block-device" and "total_size" must be set.
+At least one of "dmesg-size" or "pmsg-size" must be set non-zero.
+Required properties:
+- compatible: must be "blkoops".
+Optional properties:
+- block-device: The block device to use. Most of the time, it is a partition of
+ device. If block-device is NULL, no block device is effective
+ and the data will be lost after rebooting.
+ It accept the following variants:
+ 1) <hex_major><hex_minor> device number in hexadecimal
+ represents itself no leading 0x, for example b302.
+ 2) /dev/<disk_name> represents the device number of disk
+ 3) /dev/<disk_name><decimal> represents the device number of
+ partition - device number of disk plus the partition number
+ 4) /dev/<disk_name>p<decimal> - same as the above, that form is
+ used when disk name of partitioned disk ends on a digit.
+ 5) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing
+ the unique id of a partition if the partition table provides
+ it. The UUID may be either an EFI/GPT UUID, or refer to an
+ MSDOS partition using the format SSSSSSSS-PP, where SSSSSSSS
+ is a zero-filled hex representation of the 32-bit
+ "NT disk signature", and PP is a zero-filled hex
+ representation of the 1-based partition number.
+ 6) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in
+ relation to a partition with a known unique id.
+ 7) <major>:<minor> major and minor number of the device
+ separated by a colon.
+- total-size: The total size in kbytes pstore/blk can use. It must be a multiple
+ of 4. It must be less than or equal to size of block-device. If
+ total-size is zero with block-devce valid, it will be set to equal
+ to size of block-device.
+- dmesg-size: maximum size in kbytes of each dump done on oops, which must be a
+ multiple of 4.
+- pmsg-size: maximum size in kbytes for userspace messages, which must be a
+ multiple of 4.
index 51029a4..f49dd37 100644
@@ -12318,6 +12318,7 @@ F: drivers/firmware/efi/efi-pstore.c
F: drivers/acpi/apei/erst.c
F: Documentation/admin-guide/ramoops.rst
F: Documentation/devicetree/bindings/reserved-memory/ramoops.txt
+F: Documentation/devicetree/bindings/pstore-block/
K: \b(pstore|ramoops)