This patch includes the basic infrastructure to use swiotlb
bounce buffering on 32-bit powerpc. It is not yet enabled on
any platforms. Probably the most interesting bit is the
addition of addr_needs_map to dma_ops - we need this as
a dma_op because the decision of whether or not an addr
can be mapped by a device is device-specific.
Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The implementation we just revived has issues, such as using a
Kconfig-defined virtual address area in kernel space that nothing
actually carves out (and thus will overlap whatever is there),
or having some dependencies on being self contained in a single
PTE page which adds unnecessary constraints on the kernel virtual
address space.
This fixes it by using more classic PTE accessors and automatically
locating the area for consistent memory, carving an appropriate hole
in the kernel virtual address space, leaving only the size of that
area as a Kconfig option. It also brings some dma-mask related fixes
from the ARM implementation which was almost identical initially but
grew its own fixes.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now that we set archdata for of_platform and platform devices via
platform_notify() we no longer need to special case having a NULL device
pointer or NULL archdata. It should be a driver error if this condition
shows up and the driver should be fixed.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Change #define stubs of dma_sync ops to be empty static inlines
to avoid build warning.
Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We need to swap these out once we start using swiotlb, so add
them to dma_ops. Create CONFIG_PPC_NEED_DMA_SYNC_OPS Kconfig
option; this is currently enabled automatically if we're
CONFIG_NOT_COHERENT_CACHE. In the future, this will also
be enabled for builds that need swiotlb. If PPC_NEED_DMA_SYNC_OPS
is not defined, the dma_sync_*_for_* ops compile to nothing.
Otherwise, they access the dma_ops pointers for the sync ops.
This patch also changes dma_sync_single_range_* to actually
sync the range - previously it was using a generous
dma_sync_single. dma_sync_single_* is now implemented
as a dma_sync_single_range with an offset of 0.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now that all of the remaining dma_mapping_ops have had their
map_/unmap_single functions updated to become map/unmap_page
functions, there is no need to have the map_/unmap_single function
pointers in the dma_mapping_ops.
So, this removes them and also removes the code that does the checking
for which set of functions to use.
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Acked-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We essentially adopt the 64-bit dma code, with some changes to support
32-bit systems, including HIGHMEM. dma functions on 32-bit are now
invoked via accessor functions which call the correct op for a device based
on archdata dma_ops. If there is no archdata dma_ops, this defaults
to dma_direct_ops.
In addition, the dma_map/unmap_page functions are added to dma_ops
because we can't just fall back on map/unmap_single when HIGHMEM is
enabled. In the case of dma_direct_*, we stop using map/unmap_single
and just use the page version - this saves a lot of ugly
ifdeffing. We leave map/unmap_single in the dma_ops definition,
though, because they are needed by the iommu code, which does not
implement map/unmap_page. Ideally, going forward, we will completely
eliminate map/unmap_single and just have map/unmap_page, if it's
workable for 64-bit.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
from include/asm-powerpc. This is the result of a
mkdir arch/powerpc/include/asm
git mv include/asm-powerpc/* arch/powerpc/include/asm
Followed by a few documentation/comment fixups and a couple of places
where <asm-powepc/...> was being used explicitly. Of the latter only
one was outside the arch code and it is a driver only built for powerpc.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
