Commit graph

17 commits

Author SHA1 Message Date
Nicolas Pitre
58edb51572 [ARM] make page_to_dma() highmem aware
If a machine class has a custom __virt_to_bus() implementation then it
must provide a __arch_page_to_dma() implementation as well which is
_not_ based on page_address() to support highmem.

This patch fixes existing __arch_page_to_dma() and provide a default
implementation otherwise.  The default implementation for highmem is
based on __pfn_to_bus() which is defined only when no custom
__virt_to_bus() is provided by the machine class.

That leaves only ebsa110 and footbridge which cannot support highmem
until they provide their own __arch_page_to_dma() implementation.
But highmem support on those legacy platforms with limited memory is
certainly not a priority.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:21 -04:00
Nicolas Pitre
43377453af [ARM] introduce dma_cache_maint_page()
This is a helper to be used by the DMA mapping API to handle cache
maintenance for memory identified by a page structure instead of a
virtual address.  Those pages may or may not be highmem pages, and
when they're highmem pages, they may or may not be virtually mapped.
When they're not mapped then there is no L1 cache to worry about. But
even in that case the L2 cache must be processed since unmapped highmem
pages can still be L2 cached.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:21 -04:00
Russell King
1124d6d21f [ARM] dma: correct dma_supported() implementation
dma_supported() is supposed to indicate whether the system can support
the DMA mask it was passed, which depends on the maximal address which
can be returned for DMA allocations.  If the mask is smaller than that,
we are unable to guarantee that the driver can reliably obtain suitable
memory.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-12-13 09:12:07 +00:00
Russell King
9fa767928f [ARM] dma-mapping: fix compiler warning
arch/arm/mm/dma-mapping.c: In function `dma_sync_sg_for_cpu':
arch/arm/mm/dma-mapping.c:588: warning: statement with no effect

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-11-13 14:33:51 +00:00
Russell King
7807c6098a [ARM] dma: fix some comments in dma-mapping.h
... to prevent people being mislead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-30 11:30:53 +01:00
Russell King
309dbbabee [ARM] dma: don't touch cache on dma_*_for_cpu()
As per the dma_unmap_* calls, we don't touch the cache when a DMA
buffer transitions from device to CPU ownership.  Presently, no
problems have been identified with speculative cache prefetching
which in itself is a new feature in later architectures.  We may
have to revisit the DMA API later for these architectures anyway.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-30 11:01:36 +01:00
Russell King
0e18b5d7c6 [ARM] dma: add validation of DMA params
Validate the direction argument like x86 does.  In addition,
validate the dma_unmap_* parameters against those passed to
dma_map_* when using the DMA bounce code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-29 13:54:28 +01:00
Russell King
3216a97bb0 [ARM] dma: coding style cleanups
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-29 10:41:02 +01:00
Russell King
125ab12acf [ARM] dma: fix dmabounce dma_sync_xxx() implementations
The dmabounce dma_sync_xxx() implementation have been broken for
quite some time; they all copy data between the DMA buffer and
the CPU visible buffer no irrespective of the change of ownership.
(IOW, a DMA_FROM_DEVICE mapping copies data from the DMA buffer
to the CPU buffer during a call to dma_sync_single_for_device().)

Fix it by getting rid of sync_single(), moving the contents into
the recently created dmabounce_sync_for_xxx() functions and adjusting
appropriately.

This also makes it possible to properly support the DMA range sync
functions.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-29 10:40:22 +01:00
Russell King
8c8a0ec57e [ARM] dma: use new dmabounce_sync_for_xxx() for dma_sync_single_xxx()
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-29 10:40:16 +01:00
Russell King
2638b4dbe7 [ARM] dma: Reduce to one dma_sync_sg_* implementation
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-29 10:40:16 +01:00
Russell King
56f55f8b58 [ARM] dma: provide a better dma_map_page() implementation
We can translate a struct page directly to a DMA address using
page_to_dma().  No need to use page_address() followed by
virt_to_dma().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-25 23:39:24 +01:00
Russell King
afd1a321c4 [ARM] Update dma_map_sg()/dma_unmap_sg() API
Update the ARM DMA scatter gather APIs for the scatterlist changes.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-25 20:48:45 +01:00
Russell King
9dd4286805 [ARM] dma-mapping: provide sync_range APIs
Convert the existing dma_sync_single_for_* APIs to the new range based
APIs, and make the dma_sync_single_for_* API a superset of it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-10 14:05:14 +01:00
Russell King
98ed7d4b1a [ARM] dma-mapping: improve type-safeness of DMA translations
OMAP at least gets the return type(s) for the DMA translation functions
wrong, which can lead to subtle errors.  Avoid this by moving the DMA
translation functions to asm/dma-mapping.h, and converting them to
inline functions.

Fix the OMAP DMA translation macros to use the correct argument and
result types.

Also, remove the unnecessary casts in dmabounce.c.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-10 12:10:49 +01:00
Linus Torvalds
7e31aa11fc Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm:
  [ARM] 5182/1: pxa: Fix pcm990 compilation
  [ARM] Fix explicit asm(-arm)?/arch-foo references
  [ARM] move include/asm-arm to arch/arm/include/asm
  [ARM] Remove explicit dependency for misc.o from compressed/Makefile
  [ARM] initrd: claim initrd memory exclusively
  [ARM] pxa: add support for L2 outer cache on XScale3 (attempt 2)
  [ARM] 5180/1: at91: Fix at91_nand -> atmel_nand rename fallout
  [ARM] add Sascha Hauer as Freescale i.MX Maintainer
  [ARM] i.MX: add missing clock functions exports
  [ARM] i.MX: remove set_imx_fb_info() export
  [ARM] mx1ads: make mmc platform data available for modules
  [ARM] mx2: add missing Kconfig dependency
2008-08-03 10:39:02 -07:00
Russell King
4baa992243 [ARM] move include/asm-arm to arch/arm/include/asm
Move platform independent header files to arch/arm/include/asm, leaving
those in asm/arch* and asm/plat* alone.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-02 21:32:35 +01:00
Renamed from include/asm-arm/dma-mapping.h (Browse further)