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| author |   Linus Torvalds <torvalds@linux-foundation.org> | 2021-04-27 10:08:10 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-04-27 10:08:10 -0700 |
| commit | 288321a9c65192878446a00acaa9f6c3ca9bb1f5 (patch) | |
| tree | d61bceb24d7438de2c965af7883bcfd0ffd828a6 /Documentation | |
| parent | Merge tag 'seccomp-v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux (diff) | |
| parent | pstore: Add mem_type property DT parsing support (diff) | |
| download | linux-dev-288321a9c65192878446a00acaa9f6c3ca9bb1f5.tar.xz linux-dev-288321a9c65192878446a00acaa9f6c3ca9bb1f5.zip | |
Merge tag 'pstore-v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull pstore update from Kees Cook:
- Add mem_type property to expand support for >2 memory types (Mukesh Ojha)
* tag 'pstore-v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
pstore: Add mem_type property DT parsing support
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/admin-guide/ramoops.rst | 4 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/reserved-memory/ramoops.txt | 10 |
2 files changed, 11 insertions, 3 deletions
diff --git a/Documentation/admin-guide/ramoops.rst b/Documentation/admin-guide/ramoops.rst index b0a1ae7df13b..8f107d8c9261 100644 --- a/Documentation/admin-guide/ramoops.rst +++ b/Documentation/admin-guide/ramoops.rst @@ -3,7 +3,7 @@ Ramoops oops/panic logger Sergiu Iordache <sergiu@chromium.org> -Updated: 17 November 2011 +Updated: 10 Feb 2021 Introduction ------------ @@ -30,6 +30,8 @@ mapping to pgprot_writecombine. Setting ``mem_type=1`` attempts to use depends on atomic operations. At least on ARM, pgprot_noncached causes the memory to be mapped strongly ordered, and atomic operations on strongly ordered memory are implementation defined, and won't work on many ARMs such as omaps. +Setting ``mem_type=2`` attempts to treat the memory region as normal memory, +which enables full cache on it. This can improve the performance. The memory area is divided into ``record_size`` chunks (also rounded down to power of two) and each kmesg dump writes a ``record_size`` chunk of diff --git a/Documentation/devicetree/bindings/reserved-memory/ramoops.txt b/Documentation/devicetree/bindings/reserved-memory/ramoops.txt index b7886fea368c..b571ef6dab0f 100644 --- a/Documentation/devicetree/bindings/reserved-memory/ramoops.txt +++ b/Documentation/devicetree/bindings/reserved-memory/ramoops.txt @@ -42,8 +42,14 @@ Optional properties: - 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) +- mem-type: if present, sets the type of mapping is to be used to map the + reserved region. mem-type: 0 = write-combined (default), 1 = unbuffered, + 2 = cached. + +- unbuffered: deprecated, use mem_type instead. If present, and mem_type is + not specified, it is equivalent to mem_type = 1 and uses unbuffered mappings + to map the reserved region (defaults to buffered mappings mem_type = 0). If + both are specified -- "mem_type" overrides "unbuffered". - max-reason: if present, sets maximum type of kmsg dump reasons to store (defaults to 2: log Oopses and Panics). This can be set to INT_MAX to |