diff options
| author | Marek Szyprowski <m.szyprowski@samsung.com> | 2011-12-29 13:09:51 +0100 |
|---|---|---|
| committer | Hiroshi Doyu <hdoyu@nvidia.com> | 2012-09-07 11:46:05 +0300 |
| commit | 8f209180915de3219f087a9ba6743bb815cd567e (patch) | |
| tree | 56116dc18b906098288cb6ebd176a2d9f48b0329 /Documentation | |
| parent | e0ceb1c6cdb4b37cd0713f940cf83364274d7500 (diff) | |
ARM: integrate CMA with DMA-mapping subsystem
This patch adds support for CMA to dma-mapping subsystem for ARM
architecture. By default a global CMA area is used, but specific devices
are allowed to have their private memory areas if required (they can be
created with dma_declare_contiguous() function during board
initialisation).
Contiguous memory areas reserved for DMA are remapped with 2-level page
tables on boot. Once a buffer is requested, a low memory kernel mapping
is updated to to match requested memory access type.
GFP_ATOMIC allocations are performed from special pool which is created
early during boot. This way remapping page attributes is not needed on
allocation time.
CMA has been enabled unconditionally for ARMv6+ systems.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
CC: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Rob Clark <rob.clark@linaro.org>
Tested-by: Ohad Ben-Cohen <ohad@wizery.com>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Tested-by: Robert Nelson <robertcnelson@gmail.com>
Tested-by: Barry Song <Baohua.Song@csr.com>
Conflicts:
arch/arm/mm/mmu.c
Change-Id: I6d2b534e6ea7b1e1eb6824fa6ce554c9656963f2
Signed-off-by: Hiroshi DOYU <hdoyu@nvidia.com>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 96b1cfa61e78..29247d61abfa 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -520,6 +520,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. a hypervisor. Default: yes + coherent_pool=nn[KMG] [ARM,KNL] + Sets the size of memory pool for coherent, atomic dma + allocations if Contiguous Memory Allocator (CMA) is used. + code_bytes [X86] How many bytes of object code to print in an oops report. Range: 0 - 8192 |