Commit Graph

103 Commits

Author SHA1 Message Date
Hyun Kwon
7cbb0c63de dmaengine: xilinx: dpdma: Add the Xilinx DisplayPort DMA engine driver
The ZynqMP DisplayPort subsystem includes a DMA engine called DPDMA with
6 DMa channels (4 for display and 2 for audio). This driver exposes the
DPDMA through the dmaengine API, to be used by audio (ALSA) and display
(DRM) drivers for the DisplayPort subsystem.

Signed-off-by: Hyun Kwon <hyun.kwon@xilinx.com>
Signed-off-by: Tejas Upadhyay <tejasu@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://lore.kernel.org/r/20200717013337.24122-4-laurent.pinchart@ideasonboard.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-07-17 11:37:59 +05:30
Rafał Hibner
ee63fab3cc dmaengine: zynqmp_dma: Move list_del inside zynqmp_dma_free_descriptor.
List elements are not formally removed from list during zynqmp_dma_reset.

Signed-off-by: Rafal Hibner <rafal.hibner@secom.com.pl>
Link: https://lore.kernel.org/r/20200506102844.2259-1-rafal.hibner@secom.com.pl
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-05-15 11:21:11 +05:30
Sebastian von Ohr
b269426011 dmaengine: xilinx_dma: Add missing check for empty list
The DMA transfer might finish just after checking the state with
dma_cookie_status, but before the lock is acquired. Not checking
for an empty list in xilinx_dma_tx_status may result in reading
random data or data corruption when desc is written to. This can
be reliably triggered by using dma_sync_wait to wait for DMA
completion.

Signed-off-by: Sebastian von Ohr <vonohr@smaract.com>
Tested-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/20200303130518.333-1-vonohr@smaract.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-04-15 21:42:11 +05:30
Radhey Shyam Pandey
14ccf0aab4 dmaengine: xilinx_dma: In dma channel probe fix node order dependency
In overlay application we noticed that dma channel node probe order is
inverted i.e s2mm channel is probed first followed by mm2s channel. The
reason for this inversion is fdtoverlay utility which uses a function
called fdt_add_subnode(*). It stores the subnodes after the properties,
this has the effect of inserting the new subnode before any others and
the end result is a reversal.

Because of this inverted channel probe order, the node probed first is
assigned a '0' index instead of Channel ID should be '0' for tx and '1'
for rx and dmatest client using the DT convention fails in dma transfer
as channel are swapped.

To fix above behavior and make channel assignment index independent
of probe order, always assign mm2s channel at '0' index and the s2mm
channel at IP specific fixed offset derived from the max_channels
count.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1580388865-9960-3-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25 11:17:54 +05:30
Radhey Shyam Pandey
04c2bc2bed dmaengine: xilinx_dma: Extend dma_config structure to store max channel count
Extend dma_config structure to store the max channel count. This input is
used to populate dma device channel nodes at the fixed offset. It serves
as a preparatory patch for removing dma channel DT node order dependency,
added in the subsequent commit.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1580388865-9960-2-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25 11:17:53 +05:30
Radhey Shyam Pandey
2575cb81a9 dmaengine: xilinx_dma: Reset DMA channel in dma_terminate_all
Reset DMA channel after stop to ensure that pending transfers and FIFOs
in the datapath are flushed or completed. It also cleanup the terminate
path and removes stop for the cyclic mode as after the reset stop is not
required. This fixes intermittent data verification failure when xilinx
dma test the client is stressed and loaded/unloaded multiple times.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1580283909-32678-1-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24 22:23:48 +05:30
Matthias Fend
cc88525ebf dmaengine: zynqmp_dma: fix burst length configuration
Since the dma engine expects the burst length register content as
power of 2 value, the burst length needs to be converted first.
Additionally add a burst length range check to avoid corrupting unrelated
register bits.

Signed-off-by: Matthias Fend <matthias.fend@wolfvision.net>
Link: https://lore.kernel.org/r/20200115102249.24398-1-matthias.fend@wolfvision.net
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-21 14:49:30 +05:30
Vinod Koul
bb5a471de9 Merge branch 'fixes' into next 2019-11-14 16:02:51 +05:30
Radhey Shyam Pandey
6ccd692bfb dmaengine: xilinx_dma: Add Xilinx AXI MCDMA Engine driver support
Add support for AXI Multichannel Direct Memory Access (AXI MCDMA)
core, which is a soft Xilinx IP core that provides high-bandwidth
direct memory access between memory and AXI4-Stream target peripherals.
The AXI MCDMA core provides scatter-gather interface with multiple
independent transmit and receive channels. The driver supports
device_prep_slave_sg slave transfer mode.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1571763622-29281-7-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-11-06 22:38:02 +05:30
Radhey Shyam Pandey
c2f6b67db2 dmaengine: xilinx_dma: Extend dma_config struct to store irq routine handle
Extend dma_config structure to store irq routine handle. It enables runtime
handler selection based on xdma_ip_type and serves as preparatory patch for
adding MCDMA IP support.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Suggested-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/1571763622-29281-6-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-11-06 22:38:01 +05:30
Radhey Shyam Pandey
bcb2dc7b6c dmaengine: xilinx_dma: Remove axidma multichannel mode support
The AXI DMA multichannel support is deprecated in the IP and it is no
longer actively supported. For multichannel support, refer to the AXI
multichannel direct memory access IP product guide(PG228) and MCDMA
driver. So inline with it remove axidma multichannel support from
from the driver.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1571763622-29281-5-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-11-06 22:38:01 +05:30
Nicholas Graumann
8a631a5a0f dmaengine: xilinx_dma: Clear desc_pendingcount in xilinx_dma_reset
Whenever we reset the channel, we need to clear desc_pendingcount
along with desc_submitcount. Otherwise when a new transaction is
submitted, the irq coalesce level could be programmed to an incorrect
value in the axidma case.

This behavior can be observed when terminating pending transactions
with xilinx_dma_terminate_all() and then submitting new transactions
without releasing and requesting the channel.

Signed-off-by: Nicholas Graumann <nick.graumann@gmail.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1571150904-3988-8-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-20 19:35:27 +05:30
Nicholas Graumann
722b9e6d7e dmaengine: xilinx_dma: Print debug message when no free tx segments
The driver should not run out of tx segments in normal operation. But,
if the user attempts to prepare a transaction with a large sg list,
the driver may not have enough free segments to accommodate the request.

Log a message at the debug level to inform the user in case they are
experiencing issues.

Signed-off-by: Nicholas Graumann <nick.graumann@gmail.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1571150904-3988-7-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-20 19:35:27 +05:30
Nicholas Graumann
d8bae21a48 dmaengine: xilinx_dma: Add callback_result support
Take advantage of dmaengine_desc_get_callback_invoke which allows either
a callback or callback_result to be specified. This can be useful when
using the AXI DMA transfer unknown quantities of data where the residue
contained in the result can be used to calculate the number of bytes
transferred.

Signed-off-by: Nicholas Graumann <nick.graumann@gmail.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1571150904-3988-6-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-20 19:35:27 +05:30
Nicholas Graumann
a575d0b4e6 dmaengine: xilinx_dma: Introduce xilinx_dma_get_residue
Introduce a function that can calculate residues for IPs that support it:
AXI DMA and CDMA.

Signed-off-by: Nicholas Graumann <nick.graumann@gmail.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1571150904-3988-5-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-20 19:35:27 +05:30
Radhey Shyam Pandey
95f68c6262 dmaengine: xilinx_dma: Remove residue from channel data
There is no use of storing channel data residue field. So clean it up.
In tx_status simply pass calculated residue to dma_set_residue.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1571150904-3988-4-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-20 19:35:27 +05:30
Nicholas Graumann
0f45e75e33 dmaengine: xilinx_dma: Merge get_callback and _invoke
The dma api provides a single interface to get the appropriate callback
and invoke it directly. Prefer using it.

Signed-off-by: Nicholas Graumann <nick.graumann@gmail.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1571150904-3988-3-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-20 19:35:27 +05:30
Radhey Shyam Pandey
005a017926 dmaengine: xilinx_dma: Remove desc_callback_valid check
In descriptor cleanup the call to desc_callback_valid can be safely
removed as both callback pointers i.e callback_result and callback
are anyway checked in invoke(). There is no much benefit in having
redundant checks.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Nicholas Graumann <nick.graumann@gmail.com>
Reviewed-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
Link: https://lore.kernel.org/r/1571150904-3988-2-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-20 19:35:26 +05:30
Radhey Shyam Pandey
6c6de1ddb1 dmaengine: xilinx_dma: Fix control reg update in vdma_channel_set_config
In vdma_channel_set_config clear the delay, frame count and master mask
before updating their new values. It avoids programming incorrect state
when input parameters are different from default.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Acked-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1569495060-18117-3-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-15 15:41:55 +05:30
Radhey Shyam Pandey
68fe2b520c dmaengine: xilinx_dma: Fix 64-bit simple AXIDMA transfer
In AXI DMA simple mode also pass MSB bits of source and destination
address to xilinx_write function. It fixes simple AXI DMA operation
mode using 64-bit addressing.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1569495060-18117-2-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-15 15:41:55 +05:30
Radhey Shyam Pandey
944879ba4c dmaengine: xilinx_dma: Remove clk_get error message for probe defer
In dma probe, the driver checks for devm_clk_get return and print error
message in the failing case. However for -EPROBE_DEFER this message is
confusing so avoid it.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1569495060-18117-5-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-15 15:41:46 +05:30
Radhey Shyam Pandey
a8bd475428 dmaengine: xilinx_dma: use devm_platform_ioremap_resource()
Replace the chain of platform_get_resource() and devm_ioremap_resource()
with devm_platform_ioremap_resource(). It simplifies the flow and there
is no functional change.

Fixes below cocinelle warning-
WARNING: Use devm_platform_ioremap_resource for xdev -> regs

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1569495060-18117-4-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-15 15:41:46 +05:30
Linus Torvalds
47ebe00b68 dmaengine updates for v5.3-rc1
- Add support in dmaengine core to do device node checks for DT devices and
    update bunch of drivers to use that and remove open coding from drivers
  - New driver/driver support for new hardware, namely:
    - MediaTek UART APDMA
    - Freescale i.mx7ulp edma2
    - Synopsys eDMA IP core version 0
    - Allwinner H6 DMA
  - Updates to axi-dma and support for interleaved cyclic transfers
  - Greg's debugfs return value check removals on drivers
  - Updates to stm32-dma, hsu, dw, pl330, tegra drivers
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJdLKxYAAoJEHwUBw8lI4NHsH8P/AqYZpUlLthe5L4qItzM1Uf0
 HqxsJYs0xworjSRml8uptx/TzjIgJnJfEk2PV5VA+0zJNz/HnH7lDH85wKDx1Ydl
 AatUuyAFRO3GZOup/hY0AEIPhoIMdg/3zS2aapjJmaEZCVK2eVKmcj0KMvO5g0cw
 tsmXm3O0xd2Na1ToslNyYgFfCn8ortuAeoKiXJxhivMbGjRfw4LW/RPgS17Vspvh
 mEuxNXFWAZ+DorgPF5BmDPZ+LXcGgCXGNIoj64W+VHaXU5yXnlky+6/0f7cEcFEd
 yl3hjXVwyAq5zIItIOmiuozZidi5yfoizXg4S2ZD3P4xXKZ5OZ9Gf/0SMyXUIErU
 pwGxo6ZgsBcEpAHtqySELQedttttID+jYYeWU6oDr2LOy3W3F7AHOEGg9l9ZllLh
 gRdIoz3PrMK1wy/9Ytl37xklZyBk+HJLkeoIAvjrNgNJ1YRKqcysUCwsmqO7SG3N
 HnIGx74sG8ChljT/yX5pElq3ip6qLdb4pJcsfxKJ9VSxsTZ3JNINGNQtvI19hKR/
 6sn/c1Rb5/S1WxINGr+2FxChxXF8OESCN6GIEu6mNYVBzQnNPzwgPxfAGCqdoOOH
 mqXXgYNePMaBGYXBkdgvP1CnqenRRmTYo/1L4QmI4Mve4xpd5zhx5cZt9FlQJ2Im
 /hVT8gZ6bIrutsVOy4rg
 =R+aC
 -----END PGP SIGNATURE-----

Merge tag 'dmaengine-5.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine updates from Vinod Koul:

 - Add support in dmaengine core to do device node checks for DT devices
   and update bunch of drivers to use that and remove open coding from
   drivers

 - New driver/driver support for new hardware, namely:
     - MediaTek UART APDMA
     - Freescale i.mx7ulp edma2
     - Synopsys eDMA IP core version 0
     - Allwinner H6 DMA

 - Updates to axi-dma and support for interleaved cyclic transfers

 - Greg's debugfs return value check removals on drivers

 - Updates to stm32-dma, hsu, dw, pl330, tegra drivers

* tag 'dmaengine-5.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (68 commits)
  dmaengine: Revert "dmaengine: fsl-edma: add i.mx7ulp edma2 version support"
  dmaengine: at_xdmac: check for non-empty xfers_list before invoking callback
  Documentation: dmaengine: clean up description of dmatest usage
  dmaengine: tegra210-adma: remove PM_CLK dependency
  dmaengine: fsl-edma: add i.mx7ulp edma2 version support
  dt-bindings: dma: fsl-edma: add new i.mx7ulp-edma
  dmaengine: fsl-edma-common: version check for v2 instead
  dmaengine: fsl-edma-common: move dmamux register to another single function
  dmaengine: fsl-edma: add drvdata for fsl-edma
  dmaengine: Revert "dmaengine: fsl-edma: support little endian for edma driver"
  dmaengine: rcar-dmac: Reject zero-length slave DMA requests
  dmaengine: dw: Enable iDMA 32-bit on Intel Elkhart Lake
  dmaengine: dw-edma: fix semicolon.cocci warnings
  dmaengine: sh: usb-dmac: Use [] to denote a flexible array member
  dmaengine: dmatest: timeout value of -1 should specify infinite wait
  dmaengine: dw: Distinguish ->remove() between DW and iDMA 32-bit
  dmaengine: fsl-edma: support little endian for edma driver
  dmaengine: hsu: Revert "set HSU_CH_MTSR to memory width"
  dmagengine: pl330: add code to get reset property
  dt-bindings: pl330: document the optional resets property
  ...
2019-07-17 09:55:43 -07:00
Thomas Gleixner
2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Vinod Koul
f935d7dc81 dmaengine: xilinx_dma: Remove set but unused ‘tail_desc’
We get a compiler warn about variable ‘tail_desc’ set but not used

drivers/dma/xilinx/xilinx_dma.c:1102:42: warning:
	variable ‘tail_desc’ set but not used [-Wunused-but-set-variable]
  struct xilinx_dma_tx_descriptor *desc, *tail_desc;

So remove it.

Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-05-22 10:45:04 +05:30
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Linus Torvalds
31ef489a02 dmaengine updates for v5.1-rc1
- dmatest updates for modularizing common struct and code
  - remove SG support for VDMA xilinx IP and updates to driver
  - Update to dw driver to support Intel iDMA controllers
    multi-block support
  - tegra updates for proper reporting of residue
  - Add Snow Ridge ioatdma device id and support for IOATDMA v3.4
  - struct_size() usage and useless LIST_HEAD cleanups in subsystem.
  - qDMA controller driver for Layerscape SoCs
  - stm32-dma PM Runtime support
  - And usual updates to imx-sdma, sprd, Documentation, fsl-edma,
    bcm2835, qcom_hidma etc
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJciVhkAAoJEHwUBw8lI4NHdVoQANDfaY1eruozJobfWX0w1b8U
 0eSCN4M/gRzL/K1nOTWTV9dZFGycGokPBn25lryX6d6VIL+yO7Ptpwls/w0inn0e
 RgVtESQodLZyxcD4iWACVfTGxqxe74/bXCRAq0OCrjt5oX+5KdsBsTrhHvB8dQin
 JWT7Mq6tii5wZHZHl9b4Ds/crxM9+pIHmlzbu5MQiPDL37X9HX4KUoLQCKrVGgZt
 3FjlKEiSS6CnBWP1cs/aHgANr/PjOIwL8SD1t5NPS3i7/2k9z1u16TmmI8SbcyHf
 y9hVy1QPlxC5V85EPYK7JW7JLILotkMToxlX/QhfaFN0PWQq04rp6PCLvObKJuB2
 36QJTwSXBM2/f9bWwkddPyo9Szb3L30K80Vx8zlxzgoXYWtFFB2BXAV57M/I48j2
 gMnxEMZpHD3IupeqlykCmssClVVmCRT8qUZHLNHTdDNu48rLuNlZestFGyBS2Ma2
 D4UcJPiA/IxENy1rz54XoCajL/BIJOsFXXVRikjj3vfbV0Uir0uB9puzwfemMtKz
 tCrJbKwnnDtN30vBZtU7hVu/t4lFYYnl2c945+SpeQC69dysz3IFQGem0kxVHKnH
 INdQH4Od7nQbVQer1EXg4+h3n/rUbcYx/0iLE6JAYyOT80wE+KSlrQ5etqyJ3/qh
 1BxvU49PkUUPzw7aUGgS
 =Ykvn
 -----END PGP SIGNATURE-----

Merge tag 'dmaengine-5.1-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine updates from Vinod Koul:

 - dmatest updates for modularizing common struct and code

 - remove SG support for VDMA xilinx IP and updates to driver

 - Update to dw driver to support Intel iDMA controllers multi-block
   support

 - tegra updates for proper reporting of residue

 - Add Snow Ridge ioatdma device id and support for IOATDMA v3.4

 - struct_size() usage and useless LIST_HEAD cleanups in subsystem.

 - qDMA controller driver for Layerscape SoCs

 - stm32-dma PM Runtime support

 - And usual updates to imx-sdma, sprd, Documentation, fsl-edma,
   bcm2835, qcom_hidma etc

* tag 'dmaengine-5.1-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (81 commits)
  dmaengine: imx-sdma: fix consistent dma test failures
  dmaengine: imx-sdma: add a test for imx8mq multi sdma devices
  dmaengine: imx-sdma: add clock ratio 1:1 check
  dmaengine: dmatest: move test data alloc & free into functions
  dmaengine: dmatest: add short-hand `buf_size` var in dmatest_func()
  dmaengine: dmatest: wrap src & dst data into a struct
  dmaengine: ioatdma: support latency tolerance report (LTR) for v3.4
  dmaengine: ioatdma: add descriptor pre-fetch support for v3.4
  dmaengine: ioatdma: disable DCA enabling on IOATDMA v3.4
  dmaengine: ioatdma: Add Snow Ridge ioatdma device id
  dmaengine: sprd: Change channel id to slave id for DMA cell specifier
  dt-bindings: dmaengine: sprd: Change channel id to slave id for DMA cell specifier
  dmaengine: mv_xor: Use correct device for DMA API
  Documentation :dmaengine: clarify DMA desc. pointer after submission
  Documentation: dmaengine: fix dmatest.rst warning
  dmaengine: k3dma: Add support for dma-channel-mask
  dmaengine: k3dma: Delete axi_config
  dmaengine: k3dma: Upgrade k3dma driver to support hisi_asp_dma hardware
  Documentation: bindings: dma: Add binding for dma-channel-mask
  Documentation: bindings: k3dma: Extend the k3dma driver binding to support hisi-asp
  ...
2019-03-14 09:11:54 -07:00
YueHaibing
c2be36ac21 dmaengine: xilinx_dma: remove set but not used variable 'tail_segment'
Fixes gcc '-Wunused-but-set-variable' warning:

drivers/dma/xilinx/xilinx_dma.c: In function 'xilinx_vdma_start_transfer':
drivers/dma/xilinx/xilinx_dma.c:1104:33: warning:
 variable 'tail_segment' set but not used [-Wunused-but-set-variable]

It not used since commit b8349172b4 ("dmaengine: xilinx_dma: Drop SG support
for VDMA IP")

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-01-20 10:53:29 +05:30
Luis Chamberlain
750afb08ca cross-tree: phase out dma_zalloc_coherent()
We already need to zero out memory for dma_alloc_coherent(), as such
using dma_zalloc_coherent() is superflous. Phase it out.

This change was generated with the following Coccinelle SmPL patch:

@ replace_dma_zalloc_coherent @
expression dev, size, data, handle, flags;
@@

-dma_zalloc_coherent(dev, size, handle, flags)
+dma_alloc_coherent(dev, size, handle, flags)

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
[hch: re-ran the script on the latest tree]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-01-08 07:58:37 -05:00
Andrea Merello
b8349172b4 dmaengine: xilinx_dma: Drop SG support for VDMA IP
xilinx_vdma_start_transfer() is used only for VDMA IP, still it contains
conditional code on has_sg variable. has_sg is set only whenever the HW
does support SG mode, that is never true for VDMA IP.

This patch drops the never-taken branches.

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-01-07 09:53:12 +05:30
Andrea Merello
05f7ea7f6e dmaengine: xilinx_dma: autodetect whether the HW supports scatter-gather
The AXIDMA and CDMA HW can be either direct-access or scatter-gather
version. These are SW incompatible.

The driver can handle both versions: a DT property was used to
tell the driver whether to assume the HW is in scatter-gather mode.

This patch makes the driver to autodetect this information. The DT
property is not required anymore.

No changes for VDMA.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: devicetree@vger.kernel.org
Cc: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-01-07 09:53:12 +05:30
Radhey Shyam Pandey
ae809690b4 dmaengine: xilinx_dma: program hardware supported buffer length
AXI-DMA IP supports configurable (c_sg_length_width) buffer length
register width, hence read buffer length (xlnx,sg-length-width) DT
property and ensure that driver doesn't program buffer length
exceeding the supported limit. For VDMA and CDMA there is no change.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Andrea Merello <andrea.merello@gmail.com> [rebase, reword]
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-01-07 09:53:11 +05:30
Andrea Merello
5c094d4cac dmaengine: xilinx_dma: in axidma slave_sg and dma_cyclic mode align split descriptors
Whenever a single or cyclic transaction is prepared, the driver
could eventually split it over several SG descriptors in order
to deal with the HW maximum transfer length.

This could end up in DMA operations starting from a misaligned
address. This seems fatal for the HW if DRE (Data Realignment Engine)
is not enabled.

This patch eventually adjusts the transfer size in order to make sure
all operations start from an aligned address.

Cc: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-01-07 09:53:11 +05:30
Andrea Merello
616f0f81d8 dmaengine: xilinx_dma: commonize DMA copy size calculation
This patch removes a bit of duplicated code by introducing a new
function that implements calculations for DMA copy size, and
prepares for changes to the copy size calculation that will
happen in following patches.

Suggested-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-01-07 09:53:11 +05:30
Vinod Koul
660611827c Merge branch 'topic/xilinx' into for-linus 2018-12-31 19:32:32 +05:30
Michael Tretter
a5b21a8ba2 dmaengine: zynqmp_dma: replace spin_lock_bh with spin_lock_irqsave
All device_prep_dma_* functions and device_issue_pending can be called
from an interrupt context. As this includes hard IRQs, we must use
spin_lock_irqsave() instead of spin_lock_bh() to access chan->lock.

Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-12-05 14:37:32 +05:30
Nathan Chancellor
aeaebcc17c dmaengine: xilinx_dma: Remove __aligned attribute on zynqmp_dma_desc_ll
Clang warns:

drivers/dma/xilinx/zynqmp_dma.c:166:4: warning: attribute 'aligned' is
ignored, place it after "struct" to apply attribute to type declaration
[-Wignored-attributes]
}; __aligned(64)
   ^
./include/linux/compiler_types.h:200:38: note: expanded from macro
'__aligned'
                                               ^
1 warning generated.

As Nick pointed out in the previous version of this patch, the author
likely intended for this struct to be 8-byte (64-bit) aligned, not
64-byte, which is the default. Remove the hanging __aligned attribute.

Fixes: b0cc417c16 ("dmaengine: Add Xilinx zynqmp dma engine driver support")
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-11-24 19:11:20 +05:30
Radhey Shyam Pandey
0e03aca265 dmaengine: xilinx_dma: Fix 64-bit simple CDMA transfer
In AXI CDMA simple mode also pass MSB bits of source and destination
address to xilinx_write function. This fixes simple CDMA operation
mode using 64-bit addressing.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Appana Durga Kedareswara Rao <appana.durga.rao@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-11-11 16:03:53 +05:30
Radhey Shyam Pandey
4e47d24a90 dmaengine: xilinx_dma: Introduce helper macro for preparing dma address
This patch introduces the xilinx_prep_dma_addr_t macro which prepares
dma_addr_t from hardware buffer descriptor LSB and MSB fields. It will
be used in simple dma 64-bit programming sequence.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Reviewed-by: Appana Durga Kedareswara Rao <appana.durga.rao@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-11-11 16:03:30 +05:30
Radhey Shyam Pandey
91b438286e dmaengine: xilinx_dma: Refactor axidma channel allocation
In axidma alloc_chan_resources merge BD and cyclic BD allocation.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-11-11 16:03:09 +05:30
Radhey Shyam Pandey
0894aa28ae dmaengine: xilinx_dma: Enable VDMA S2MM vertical flip support
Vertical flip state is exported in xilinx_vdma_config and depending
on IP configuration(c_enable_vert_flip) vertical flip state is
programmed in hardware.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-06-29 14:20:00 +05:30
Kees Cook
6396bb2215 treewide: kzalloc() -> kcalloc()
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Kedareswara rao Appana
0e847d44b3 dmaengine: xilinx_dma: Free BD consistent memory
Free BD consistent memory while freeing the channel
i.e in free_chan_resources.

Signed-off-by: Radhey Shyam Pandey <radheys@xilinx.com>
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2018-01-08 16:24:50 +05:30
Kedareswara rao Appana
4b597c634a dmaengine: xilinx_dma: Fix warning variable prev set but not used
This patch fixes the below sparse warning in the driver
drivers/dma/xilinx/xilinx_dma.c: In function ‘xilinx_vdma_dma_prep_interleaved’:
drivers/dma/xilinx/xilinx_dma.c:1614:43: warning: variable ‘prev’ set but not used [-Wunused-but-set-variable]
  struct xilinx_vdma_tx_segment *segment, *prev = NULL;

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2018-01-08 16:24:50 +05:30
Kedareswara rao Appana
48c62fb051 dmaengine: xilinx_dma: properly configure the SG mode bit in the driver for cdma
If the hardware is configured for Scatter Gather(SG) mode,
and hardware is idle, in the control register SG mode bit
must be set to a 0 then back to 1 by the software, to force
the CDMA SG engine to use a new value written to the CURDESC_PNTR
register, failure to do so could result errors from the dmaengine.

This patch updates the same.

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2018-01-08 16:24:50 +05:30
Vinod Koul
3093186898 dmaengine: xilinx_dma: Fix typos
some typos is comments, so fix them up
/s/enusres/ensures
/s/descripotrs/descriptors
/s/Submited/Submitted
/s/pollling/polling

Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-12-18 10:48:08 +05:30
Kedareswara rao Appana
c7a03599b5 dmaengine: xilinx_dma: Differentiate probe based on the ip type
This patch updates the probe banner info based on the ip probed.

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-12-18 10:44:09 +05:30
Kedareswara rao Appana
22653af70e dmaengine: xilinx_dma: fix style issues from checkpatch
This patch fixes below.
ERROR: open brace '{' following function definitions go on the next line
+static int xilinx_dma_child_probe(struct xilinx_dma_device *xdev,
+				    struct device_node *node) {

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-12-18 10:44:09 +05:30
Kedareswara rao Appana
e50a0ad159 dmaengine: xilinx_dma: Fix kernel doc warnings
This patch fixes the kernel doc warnings
in the driver.

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-12-18 10:44:09 +05:30
Kedareswara rao Appana
23059408b6 dmaengine: xilinx_dma: Fix race condition in the driver for multiple descriptor scenario
As per axi dmaengine spec the software must not move the tail pointer
to a location that has not been updated (next descriptor field of the
h/w descriptor should always point to a valid address).

When user submits multiple descriptors on the recv side, with the
current driver flow the last buffer descriptor next descriptor field
points to a invalid location, resulting the invalid data or errors from the
axidma dmaengine.

This patch fixes this issue by creating a buffer descritpor chain during
channel allocation itself and use those buffer descriptors for the
subsequent dma operations.

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-12-18 10:44:09 +05:30