linux-toradex.git/arch/powerpc/include/asm/dma-mapping.h, branch v4.1.20

powerpc: Use bool function return values of true/false not 1/0

2015-03-31T03:19:47+00:00

Use the normal return values for bool functions

Signed-off-by: Joe Perches 
Acked-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman

powerpc/powernv: Override dma_get_required_mask()

2014-09-30T07:15:20+00:00

The dma_get_required_mask() function is used by some drivers to
query the platform about what DMA mask is needed to cover all of
memory. This is a bit of a strange semantic when we have to choose
between IOMMU translation or bypass, but essentially what it means
is "what DMA mask will give best performances".

Currently, our IOMMU backend always returns a 32-bit mask here, we
don't do anything special to it when we have bypass available. This
causes some drivers to choose a 32-bit mask, thus losing the ability
to use the bypass window, thinking this is more efficient. The problem
was reported from the driver of following device:

0004:03:00.0 0107: 1000:0087 (rev 05)
0004:03:00.0 Serial Attached SCSI controller: LSI Logic / Symbios \
             Logic SAS2308 PCI-Express Fusion-MPT SAS-2 (rev 05)

This patch adds an override of that function in order to, instead,
return a 64-bit mask whenever a bypass window is available in order
for drivers to prefer this configuration.

Reported-by: Murali N. Iyer 
Suggested-by: Benjamin Herrenschmidt 
Signed-off-by: Gavin Shan 
Signed-off-by: Michael Ellerman

powerpc/powernv: Add iommu DMA bypass support for IODA2

2014-02-11T05:07:37+00:00

This patch adds the support for to create a direct iommu "bypass"
window on IODA2 bridges (such as Power8) allowing to bypass iommu
page translation completely for 64-bit DMA capable devices, thus
significantly improving DMA performances.

Additionally, this adds a hook to the struct iommu_table so that
the IOMMU API / VFIO can disable the bypass when external ownership
is requested, since in that case, the device will be used by an
environment such as userspace or a KVM guest which must not be
allowed to bypass translations.

Signed-off-by: Benjamin Herrenschmidt

powerpc: dma_debug: add debug_dma_mapping_error support

2012-11-28T14:28:59+00:00

Add dma-debug interface debug_dma_mapping_error() to debug drivers that fail
to check dma mapping errors on addresses returned by dma_map_single() and
dma_map_page() interfaces.

Signed-off-by: Shuah Khan 
Signed-off-by: Joerg Roedel

common: dma-mapping: add support for generic dma_mmap_* calls

2012-07-30T10:25:46+00:00

Commit 9adc5374 ('common: dma-mapping: introduce mmap method') added a
generic method for implementing mmap user call to dma_map_ops structure.

This patch converts ARM and PowerPC architectures (the only providers of
dma_mmap_coherent/dma_mmap_writecombine calls) to use this generic
dma_map_ops based call and adds a generic cross architecture
definition for dma_mmap_attrs, dma_mmap_coherent, dma_mmap_writecombine
functions.

The generic mmap virt_to_page-based fallback implementation is provided for
architectures which don't provide their own implementation for mmap method.

Signed-off-by: Marek Szyprowski 
Reviewed-by: Kyungmin Park

PowerPC: adapt for dma_map_ops changes

2012-03-28T14:36:33+00:00

Adapt core PowerPC architecture code for dma_map_ops changes: replace
alloc/free_coherent with generic alloc/free methods.

Signed-off-by: Andrzej Pietrasiewicz 
[added missing changes to arch/powerpc/kernel/vio.c]
Signed-off-by: Kyungmin Park 
Signed-off-by: Marek Szyprowski 
Reviewed-by: David Gibson 
Reviewed-by: Arnd Bergmann

powerpc: Implement dma_mmap_coherent()

2011-03-29T23:44:00+00:00

This is used by Alsa to mmap buffers allocated with dma_alloc_coherent()
into userspace. We need a special variant to handle machines with
non-coherent DMAs as those buffers have "special" virt addresses and
require non-cachable mappings

Signed-off-by: Benjamin Herrenschmidt

powerpc/dma: Add optional platform override of dma_set_mask()

2010-09-02T04:07:32+00:00

Some platforms may want to override dma_set_mask() to take into
account some specific "features" such as the availability of
a direct-map window in addition to an iommu.

Signed-off-by: Benjamin Herrenschmidt

dma-mapping: remove dma_is_consistent API

2010-08-11T15:59:21+00:00

Architectures implement dma_is_consistent() in different ways (some
misinterpret the definition of API in DMA-API.txt).  So it hasn't been so
useful for drivers.  We have only one user of the API in tree.  Unlikely
out-of-tree drivers use the API.

Even if we fix dma_is_consistent() in some architectures, it doesn't look
useful at all.  It was invented long ago for some old systems that can't
allocate coherent memory at all.  It's better to export only APIs that are
definitely necessary for drivers.

Let's remove this API.

Signed-off-by: FUJITA Tomonori 
Cc: James Bottomley 
Reviewed-by: Konrad Rzeszutek Wilk 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma-mapping: unify dma_get_cache_alignment implementations

2010-08-11T15:59:21+00:00

dma_get_cache_alignment returns the minimum DMA alignment.  Architectures
defines it as ARCH_DMA_MINALIGN (formally ARCH_KMALLOC_MINALIGN).  So we
can unify dma_get_cache_alignment implementations.

Note that some architectures implement dma_get_cache_alignment wrongly.
dma_get_cache_alignment() should return the minimum DMA alignment.  So
fully-coherent architectures should return 1.  This patch also fixes this
issue.

Signed-off-by: FUJITA Tomonori 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds