The newly added xilinx_dma_prep_dma_cyclic function sometimes causes
a gcc warning about the use of the segment function in case
we never run into the inner loop of the function:

dma/xilinx/xilinx_vdma.c: In function 'xilinx_dma_prep_dma_cyclic':
dma/xilinx/xilinx_vdma.c:1808:23: error: 'segment' may be used uninitialized in this function [-Werror=maybe-uninitialized]
   segment->hw.control |= XILINX_DMA_BD_SOP;

This can only happen if the period len is zero (which would cause other
problems earlier), or if the buffer is shorter than a period. Neither
of them should ever happen, but by adding an explicit check for these two
cases, we can abort in a more controlled way, and the compiler is
able to see that we never use uninitialized data.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch fixes the below compilation warining.
drivers/dma/xilinx/xilinx_vdma.c: In function 'xilinx_dma_prep_dma_cyclic':
drivers/dma/xilinx/xilinx_vdma.c:1808:23: warning: 'segment' may be used
uninitialized in this function [-Wmaybe-uninitialized]
   segment->hw.control |= XILINX_DMA_BD_SOP;

The start of packet (SOP) should be set to the first segment in the desc
chain not for the last segment of the desc chain.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

dma_pool_zalloc combines dma_pool_alloc and memset 0
this patch updates the driver to use dma_pool_zalloc.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch adds support for AXI DMA cyclic dma mode.
In cyclic mode, DMA fetches and processes the same
BDs without interruption. The DMA continues to fetch and process
until it is stopped or reset.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Added basic clock support for axi dma's.
The clocks are requested at probe and released at remove.
Reviewed-by: NShubhrajyoti Datta <shubhraj@xilinx.com>
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch adds config structure in the driver to differentiate
AXI DMA's and to add more features(clock support etc..) to these DMA's.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch adds support for the AXI Central Direct Memory Access
(AXI CDMA) core to the existing vdma driver, AXI CDMA is a
soft Xilinx IP core that provides high-bandwidth
Direct Memory Access(DMA) between a memory-mapped
source address and a memory-mapped destination address.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch adds support for the AXI Direct Memory Access (AXI DMA)
core in the existing vdma driver, AXI DMA Core is a
soft Xilinx IP core that provides high-bandwidth
direct memory access between memory and AXI4-Stream
type target peripherals.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch renames the xilinx_vdma_ prefix to xilinx_dma
for the API's and masks that will be shared b/w three DMA
IP cores.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Dma_pool_zalloc combines dma_pool_alloc and memset 0.  The semantic patch
that makes this transformation is as follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression d,e;
statement S;
@@

        d =
-            dma_pool_alloc
+            dma_pool_zalloc
             (...);
        if (!d) S
-       memset(d, 0, sizeof(*d));
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Acked-by: NSören Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch fixes the below checkpatch.pl warnings.

WARNING: void function return statements are not generally useful
+	return;
+}

WARNING: void function return statements are not generally useful
+	return;
+}

WARNING: Missing a blank line after declarations
+		u32 errors = status & XILINX_VDMA_DMASR_ALL_ERR_MASK;
+		vdma_ctrl_write(chan, XILINX_VDMA_REG_DMASR,
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NMoritz Fischer <moritz.fischer@ettus.com>
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

When VDMA is configured in  Non-sg mode
Users can queue descriptors greater than h/w configured frames.

Current driver allows the user to queue descriptors upto h/w configured.
Which is wrong for non-sg mode configuration.

This patch fixes this issue.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This VDMA  is a soft ip, which can be programmed to support
32 bit addressing or greater than 32 bit addressing.

When the VDMA ip is configured for 32 bit address space
the buffer address is specified by a single register
(0x5C for MM2S and 0xAC for S2MM channel).

When the  VDMA core is configured for an address space greater
than 32 then each buffer address is specified by a combination of
two registers.

The first register specifies the LSB 32 bits of address,
while the next register specifies the MSB 32 bits of address.

For example, 5Ch will specify the LSB 32 bits while 60h will
specify the MSB 32 bits of the first start address.
So we need to program two registers at a time.

This patch adds the 64 bit addressing support to the vdma driver.
Signed-off-by: NAnurag Kumar Vulisha <anuragku@xilinx.com>
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

When client request a non existing channel from of_dma_xilinx_xlate
we get a NULL pointer dereferencing. This patch fix this problem.
Signed-off-by: NFranck Jullien <franck.jullien@odyssee-systemes.fr>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch removes the unnecessary variable initializations
in the driver.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

It is sometimes necessary to poll a memory-mapped register until its
value satisfies some condition use convenience macros
that do this instead of do while loop's.

This patch updates the same in the driver.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch simplifies the spin lock handling in the driver
by moving locking out of xilinx_dma_start_transfer() API
and xilinx_dma_update_completed_cookie() API.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch fixes issues with the Non-parking mode(Cirular mode).
With the  existing driver in cirular mode if we submit frames less than h/w
configured we simply end-up having misconfigured vdma h/w.
This patch fixes this issue by configuring the frame count register.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The current driver allows user to queue up multiple segments
on to a single transaction descriptor. User will submit this single desc
and in the issue_pending() we decode multiple segments and submit to SG HW engine.
We free up the allocated_desc when it is submitted to the HW.

Existing code prevents the user to prepare multiple trasactions at same time as
we are overwrite with the allocated_desc.

The best utilization of HW SG engine would happen if we collate the pending
list when we start dma this patch updates the same.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This platform driver has a OF device ID table but the OF module
alias information is not created so module autoloading won't work.
Signed-off-by: NLuis de Bethencourt <luisbg@osg.samsung.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NMoritz Fischer <moritz.fischer@ettus.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch moves the xilinx_dma.h header file
to the include/linux/dma.
Signed-off-by: NKedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Split the device_control callback of the Xilinx VDMA driver to make use of the
newly introduced callbacks, that will eventually be used to retrieve slave
capabilities.
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch modifies the icg field to match the description
as mentioned in the DMA Linux framework.
Signed-off-by: NSrikanth Thokala <sthokal@xilinx.com>
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch adds a sanity check to see if frame_size is 1.
Signed-off-by: NSrikanth Thokala <sthokal@xilinx.com>
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The segment list in a descriptor should be checked for empty, else
it will try to access invalid address for the first call.  This
patch fixes this issue.
Signed-off-by: NSrikanth Thokala <sthokal@xilinx.com>
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

There is no need to init .owner field.

Based on the patch from Peter Griffin <peter.griffin@linaro.org>
"mmc: remove .owner field for drivers using module_platform_driver"

This patch removes the superflous .owner field for drivers which
use the module_platform_driver API, as this is overriden in
platform_driver_register anyway."
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Reviewed-by: NLevente Kurusa <lkurusa@redhat.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This is the driver for the AXI Video Direct Memory Access (AXI
VDMA) core, which is a soft Xilinx IP core that provides high-
bandwidth direct memory access between memory and AXI4-Stream
type video target peripherals. The core provides efficient two
dimensional DMA operations with independent asynchronous read
and write channel operation.

This module works on Zynq (ARM Based SoC) and Microblaze platforms.
Signed-off-by: NSrikanth Thokala <sthokal@xilinx.com>
Acked-by: NJassi Brar <jassisinghbrar@gmail.com>
Reviewed-by: NLevente Kurusa <levex@linux.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>