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| author | Mukesh Ojha <mojha@codeaurora.org> | 2021-03-22 21:42:17 +0300 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2021-03-31 20:06:23 +0300 |
| commit | 9d843e8fafc7c0b15d8f511d146c0c3d7c816634 (patch) | |
| tree | aa50c176998930654d9764bdfb5c60af2f416d55 /Documentation/admin-guide | |
| parent | a38fd8748464831584a19438cbb3082b5a2dab15 (diff) | |
| download | linux-9d843e8fafc7c0b15d8f511d146c0c3d7c816634.tar.xz | |
pstore: Add mem_type property DT parsing support
There could be a scenario where we define some region
in normal memory and use them store to logs which is later
retrieved by bootloader during warm reset.
In this scenario, we wanted to treat this memory as normal
cacheable memory instead of default behaviour which
is an overhead. Making it cacheable could improve
performance.
This commit gives control to change mem_type from Device
tree, and also documents the value for normal memory.
Signed-off-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/1616438537-13719-1-git-send-email-mojha@codeaurora.org
Diffstat (limited to 'Documentation/admin-guide')
| -rw-r--r-- | Documentation/admin-guide/ramoops.rst | 4 |
1 files changed, 3 insertions, 1 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 |