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author | Greg Hackmann <ghackmann@google.com> | 2016-01-08 00:40:56 +0100 |
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committer | Kees Cook <keescook@chromium.org> | 2016-06-14 20:34:39 +0200 |
commit | 35da60941e44dbf57868e67686dd24cc1a33125a (patch) | |
tree | 9c260e87ab53015553e1e254ce6872f1cd8f1032 /Documentation/devicetree/bindings/misc | |
parent | efi-pstore: implement efivars_pstore_exit() (diff) | |
download | linux-35da60941e44dbf57868e67686dd24cc1a33125a.tar.xz linux-35da60941e44dbf57868e67686dd24cc1a33125a.zip |
pstore/ram: add Device Tree bindings
ramoops is one of the remaining places where ARM vendors still rely on
board-specific shims. Device Tree lets us replace those shims with
generic code.
These bindings mirror the ramoops module parameters, with two small
differences:
(1) dump_oops becomes an optional "no-dump-oops" property, since ramoops
sets dump_oops=1 by default.
(2) mem_type=1 becomes the more self-explanatory "unbuffered" property.
Signed-off-by: Greg Hackmann <ghackmann@google.com>
[fixed platform_get_drvdata() crash, thanks to Brian Norris]
[switched from u64 to u32 to simplify code, various whitespace fixes]
[use dev_of_node() to gain code-elimination for CONFIG_OF=n]
Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'Documentation/devicetree/bindings/misc')
-rw-r--r-- | Documentation/devicetree/bindings/misc/ramoops.txt | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/misc/ramoops.txt b/Documentation/devicetree/bindings/misc/ramoops.txt new file mode 100644 index 000000000000..cd02cec67d38 --- /dev/null +++ b/Documentation/devicetree/bindings/misc/ramoops.txt @@ -0,0 +1,48 @@ +Ramoops oops/panic logger +========================= + +ramoops provides persistent RAM storage for oops and panics, so they can be +recovered after a reboot. It is a backend to pstore, so this node is named +"ramoops" after the backend, rather than "pstore" which is the subsystem. + +Parts of this storage may be set aside for other persistent log buffers, such +as kernel log messages, or for optional ECC error-correction data. The total +size of these optional buffers must fit in the reserved region. + +Any remaining space will be used for a circular buffer of oops and panic +records. These records have a configurable size, with a size of 0 indicating +that they should be disabled. + +At least one of "record-size", "console-size", "ftrace-size", or "pmsg-size" +must be set non-zero, but are otherwise optional as listed below. + + +Required properties: + +- compatible: must be "ramoops" + +- memory-region: phandle to a region of memory that is preserved between + reboots + + +Optional properties: + +- ecc-size: enables ECC support and specifies ECC buffer size in bytes + (defaults to 0: no ECC) + +- record-size: maximum size in bytes of each dump done on oops/panic + (defaults to 0: disabled) + +- console-size: size in bytes of log buffer reserved for kernel messages + (defaults to 0: disabled) + +- ftrace-size: size in bytes of log buffer reserved for function tracing and + profiling (defaults to 0: disabled) + +- pmsg-size: size in bytes of log buffer reserved for userspace messages + (defaults to 0: disabled) + +- unbuffered: if present, use unbuffered mappings to map the reserved region + (defaults to buffered mappings) + +- no-dump-oops: if present, only dump panics (defaults to panics and oops) |