On some MIPS systems, a subset of devices may have DMA coherent with CPU
caches. For example in systems including a MIPS I/O Coherence Unit
(IOCU), some devices may be connected to that IOCU whilst others are
not.
Prior to this patch, we have a plat_device_is_coherent() function but no
implementation which does anything besides return a global true or
false, optionally chosen at runtime. For devices such as those described
above this is insufficient.
Fix this by tracking DMA coherence on a per-device basis with a
dma_coherent field in struct dev_archdata. Setting this from
arch_setup_dma_ops() takes care of devices which set the dma-coherent
property via device tree, and any PCI devices beneath a bridge described
in DT, automatically.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14349/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
(cherry picked from commit 20d330645cfb8cfecfb82b369e4d3084e429e68a)
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Use asm-generic/dma-mapping-common.h to handle all DMA mapping operations
and establish a default get_dma_ops() that forwards all operations to the
existing code.
Augment dev_archdata to carry a pointer to the struct dma_map_ops, allowing
DMA operations to be overridden on a per device basis. Currently this is
never filled in, so the default dma_map_ops are used. A follow-on patch
sets this for Octeon PCI devices.
Also initialize the dma_debug system as it is now used if it is configured.
Includes fixes by Kevin Cernekee <cernekee@gmail.com>.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Patchwork: http://patchwork.linux-mips.org/patch/1637/
Patchwork: http://patchwork.linux-mips.org/patch/1678/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
