This patch add a complete implementation of DMA-mapping API for
devices which have IOMMU support.
This implementation tries to optimize dma address space usage by remapping
all possible physical memory chunks into a single dma address space chunk.
DMA address space is managed on top of the bitmap stored in the
dma_iommu_mapping structure stored in device->archdata. Platform setup
code has to initialize parameters of the dma address space (base address,
size, allocation precision order) with arm_iommu_create_mapping() function.
To reduce the size of the bitmap, all allocations are aligned to the
specified order of base 4 KiB pages.
dma_alloc_* functions allocate physical memory in chunks, each with
alloc_pages() function to avoid failing if the physical memory gets
fragmented. In worst case the allocated buffer is composed of 4 KiB page
chunks.
dma_map_sg() function minimizes the total number of dma address space
chunks by merging of physical memory chunks into one larger dma address
space chunk. If requested chunk (scatter list entry) boundaries
match physical page boundaries, most calls to dma_map_sg() requests will
result in creating only one chunk in dma address space.
dma_map_page() simply creates a mapping for the given page(s) in the dma
address space.
All dma functions also perform required cache operation like their
counterparts from the arm linear physical memory mapping version.
This patch contains code and fixes kindly provided by:
- Krishna Reddy <vdumpa@nvidia.com>,
- Andrzej Pietrasiewicz <andrzej.p@samsung.com>,
- Hiroshi DOYU <hdoyu@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-By: Subash Patel <subash.ramaswamy@linaro.org>
This patch modifies dma-mapping implementation on ARM architecture to
use common dma_map_ops structure and asm-generic/dma-mapping-common.h
helpers.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Tested-By: Subash Patel <subash.ramaswamy@linaro.org>
Add a private iommu pointer to the ARM-specific arch data in the
device struct, which will be used to attach iommu-specific data
to devices which require iommu support.
Different iommu implementations (on different platforms) will attach
different types of data to this pointer, so 'void *' is currently used
(the downside is reduced typesafety).
Note: ia64, x86 and sparc have this exact iommu extension as well, and
if others are likely to adopt it too, we might want to consider
adding this to the device struct itself directly.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add omap_device pointer to the ARM-specific arch data in the
platform_device. This will be used to attach OMAP-specific
device-data to the platform device with device lifetime.
Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Allow architecture specific data in struct platform_device V3.
With this patch struct pdev_archdata is added to struct
platform_device, similar to struct dev_archdata in found in
struct device. Useful for architecture code that needs to
keep extra data associated with each platform device.
Struct pdev_archdata is different from dev.platform_data, the
convention is that dev.platform_data points to driver-specific
data. It may or may not be required by the driver. The format
of this depends on driver but is the same across architectures.
The structure pdev_archdata is a place for architecture specific
data. This data is handled by architecture specific code (for
example runtime PM), and since it is architecture specific it
should _never_ be touched by device driver code. Exactly like
struct dev_archdata but for platform devices.
[rjw: This change is for power management mostly and that's why it
goes through the suspend tree.]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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>
Marek Szyprowski