Commit graph

6 commits

Author SHA1 Message Date
Akinobu Mita db6a3d03e2 dmaengine: xilinx: avoid memory corruption for device_prep_dma_memcpy()
The device_prep_dma_memcpy() callback for this driver allocates a new
xilinx_dma_tx_descriptor whose TX segments list is initialized as empty,
but then gets invalid TX segment pointer by list_last_entry() from the
empty TX segments list and memory corruption happens by the attempt to
update the next descriptor in invalid TX segment pointer.

This removes unnecessary memory access for nonexistent tail TX segment
which causes memory corruption.

Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Kedareswara rao Appana <appana.durga.rao@xilinx.com>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-03-14 16:14:29 +05:30
Akinobu Mita 676f9c26c3 dmaengine: xilinx: fix device_terminate_all() callback for AXI CDMA
The device_terminate_all() callback for this driver stops current DMA
operations by clearing RUNSTOP bit in the control register and waiting
HALTED bit set in the status register.

But AXI CDMA which is one of the supported DMA engine by this driver
does not provide the run / stop controls and those bits in the control
and status registers are reserved.  So when device_terminate_all() is
called, the error message is printed and the channel is marked as having
errors in xilinx_dma_halt().

This change adds stop_transfer() callback which differentiates CDMA and
other DMA engine.  The CDMA's one avoids the unsupported operations and
instead polls the status register to check if the DMA operations are in
progress for AXI CDMA.

Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Kedareswara rao Appana <appana.durga.rao@xilinx.com>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-03-14 16:14:29 +05:30
Vinod Koul 369dbadac1 dmengine: xilinx_dma: convert callback to helper function
Move the xilinx driver to new dmaengine callback

Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-08-08 08:11:43 +05:30
Kedareswara rao Appana e598e6eb46 dmaengine: xilinx: Fix race condition in axi dma cyclic dma mode
In cyclic DMA mode need to link the tail bd segment
with the head bd segment to process bd's in cyclic.

Current driver is doing this only for tx channel
needs to update the same for rx channel case also.

This patch fixes the same.

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-07-12 10:01:36 +05:30
Kedareswara rao Appana e131f1ba6f dmaengine: xilinx: Use different channel names for each dma
Current driver assumes that child node channel name is either
"xlnx,axi-vdma-mm2s-channel" or "xlnx,axi-vdma-s2mm-channel"
which is confusing the users of AXI DMA and CDMA.
This patch fixes this issue by using different channel
names for the AXI DMA and AXI CDMA child nodes.

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-07-08 10:51:49 +05:30
Kedareswara rao Appana fde57a7c44 dmaengine: xilinx: Rename driver and config
In the existing vdma driver support for
AXI DMA and CDMA got added so the driver is no
longer VDMA specific.

This patch renames the driver and DT binding doc to xilinx_dma
and updates the Kconfig description for all the DMAS.

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-07-08 10:51:35 +05:30
Renamed from drivers/dma/xilinx/xilinx_vdma.c (Browse further)