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authorKees Cook <keescook@chromium.org>2016-07-30 04:11:32 +0300
committerKees Cook <keescook@chromium.org>2016-08-05 21:21:36 +0300
commit529182e204db083cb7bda832d1c5c6d9278ba1cb (patch)
treeb923eedd4b5a1e2d6cdda1af5c8bfd3b18b17189 /Documentation/devicetree/bindings/reserved-memory
parentf38d2e5313f0af9d9b66c02a5d49c71deb994b85 (diff)
downloadlinux-529182e204db083cb7bda832d1c5c6d9278ba1cb.tar.xz
ramoops: use DT reserved-memory bindings
Instead of a ramoops-specific node, use a child node of /reserved-memory. This requires that of_platform_device_create() be explicitly called for the node, though, since "/reserved-memory" does not have its own "compatible" property. Suggested-by: Rob Herring <robh@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Rob Herring <robh@kernel.org>
Diffstat (limited to 'Documentation/devicetree/bindings/reserved-memory')
-rw-r--r--Documentation/devicetree/bindings/reserved-memory/ramoops.txt48
1 files changed, 48 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/reserved-memory/ramoops.txt b/Documentation/devicetree/bindings/reserved-memory/ramoops.txt
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+++ b/Documentation/devicetree/bindings/reserved-memory/ramoops.txt
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+Ramoops oops/panic logger
+=========================
+
+ramoops provides persistent RAM storage for oops and panics, so they can be
+recovered after a reboot. This is a child-node of "/reserved-memory", and
+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"
+
+- reg: 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)