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>
Replace all DMA_32BIT_MASK macro with DMA_BIT_MASK(32)
Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.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>
On PowerPC 4xx or other non cache-coherent platforms, we lost the
appropriate cache flushing in dma_map_sg() when merging the 32 and
64-bit DMA code (commit 4fc665b88a,
"powerpc: Merge 32 and 64-bit dma code"). This restores it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
After Becky's work we can almost have different DMA offsets
between on-chip devices and PCI. Almost because there's a
problem with the non-coherent DMA code that basically ignores
the programmed offset to use the global one for everything.
This fixes it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.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>
Use the struct device's numa_node instead; use accessor functions
to get/set numa_node.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
32-bit platforms are about to start using dma.c; move the iommu
dma ops into their own file to make this a bit cleaner.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This is in preparation for the merge of the 32 and 64-bit
dma code in arch/powerpc.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
