All references to the slave_id field have been removed, so remove the
field as well to prevent new references from creeping in again.
Originally this allowed slave DMA drivers to configure which device
is accessed with the dmaengine_slave_config() call, but this was
inconsistent, as the same information is also passed while requesting
a channel, and never changes in practice.
In modern kernels, the device is always selected when requesting
the channel, so the .slave_id field is no longer useful.
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20211122222203.4103644-12-arnd@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This is the old DMA_SG interface that was removed in commit
c678fa6634 ("dmaengine: remove DMA_SG as it is dead code in kernel"). It
has been renamed to DMA_MEMCPY_SG to better match the MEMSET and MEMSET_SG
naming convention.
It should only be used for mem2mem copies, either main system memory or
CPU-addressable device memory (like video memory on a PCI graphics card).
Bringing back this interface was prompted by the need to use the Xilinx
CDMA device for mem2mem SG transfers.
Signed-off-by: Adrian Larumbe <adrianml@alumnos.upm.es>
Link: https://lore.kernel.org/r/20211101180825.241048-3-adrianml@alumnos.upm.es
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The ptdma driver has added debugfs support, but this fails to build
when debugfs is disabled:
drivers/dma/ptdma/ptdma-debugfs.c: In function 'ptdma_debugfs_setup':
drivers/dma/ptdma/ptdma-debugfs.c:93:54: error: 'struct dma_device' has no member named 'dbg_dev_root'
93 | debugfs_create_file("info", 0400, pt->dma_dev.dbg_dev_root, pt,
| ^
drivers/dma/ptdma/ptdma-debugfs.c:96:55: error: 'struct dma_device' has no member named 'dbg_dev_root'
96 | debugfs_create_file("stats", 0400, pt->dma_dev.dbg_dev_root, pt,
| ^
drivers/dma/ptdma/ptdma-debugfs.c:102:52: error: 'struct dma_device' has no member named 'dbg_dev_root'
102 | debugfs_create_dir("q", pt->dma_dev.dbg_dev_root);
| ^
Remove the #ifdef in the header, as this only saves a few bytes,
but would require ugly #ifdefs in each driver using it.
Simplify the other user while we're at it.
Fixes: e2fb2e2a33 ("dmaengine: ptdma: Add debugfs entries for PTDMA")
Fixes: 26cf132de6 ("dmaengine: Create debug directories for DMA devices")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://lore.kernel.org/r/20210920122017.205975-1-arnd@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
If the DMA device supports per channel coherency configuration (a channel
can be configured to have coherent or not coherent view) then a single
device (the DMA controller's device) can not be used for dma_api for all
channels as channels can have different coherency.
Introduce custom_dma_mapping flag for the dma_chan and a new helper to get
the device pointer to be used for dma_api for the given channel.
Client drivers should be updated to be able to support per channel
coherency by:
- dma_map_single(chan->device->dev, ptr, size, DMA_TO_DEVICE);
+ struct device *dma_dev = dmaengine_get_dma_device(chan);
+
+ dma_map_single(dma_dev, ptr, size, DMA_TO_DEVICE);
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20201208090440.31792-9-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Additional configuration for the DMA event router might be needed for a
channel which can not be done during device_alloc_chan_resources callback
since the router information is not yet present for the drivers.
If there is a need for additional configuration for the channel if DMA
router is in use, then the driver can implement the device_router_config
callback.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20201208090440.31792-8-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
New drivers should use dma_request_chan() instead
dma_request_slave_channel()
dma_request_slave_channel() is a simple wrapper for dma_request_chan()
eating up the error code for channel request failure and makes deferred
probing impossible.
Move the dma_request_slave_channel() into the header as inline function,
mark it as deprecated.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20200828110507.22407-1-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Pull dmaengine updates from Vinod Koul:
"Core:
- Support out of order dma completion
- Support for repeating transaction
New controllers:
- Support for Actions S700 DMA engine
- Renesas R8A774E1, r8a7742 controller binding
- New driver for Xilinx DPDMA controller
Other:
- Support of out of order dma completion in idxd driver
- W=1 warning cleanup of subsystem
- Updates to ti-k3-dma, dw, idxd drivers"
* tag 'dmaengine-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (68 commits)
dmaengine: dw: Don't include unneeded header to platform data header
dmaengine: Actions: Add support for S700 DMA engine
dmaengine: Actions: get rid of bit fields from dma descriptor
dt-bindings: dmaengine: convert Actions Semi Owl SoCs bindings to yaml
dmaengine: idxd: add missing invalid flags field to completion
dmaengine: dw: Initialize max_sg_burst capability
dmaengine: dw: Introduce max burst length hw config
dmaengine: dw: Initialize min and max burst DMA device capability
dmaengine: dw: Set DMA device max segment size parameter
dmaengine: dw: Take HC_LLP flag into account for noLLP auto-config
dmaengine: Introduce DMA-device device_caps callback
dmaengine: Introduce max SG burst capability
dmaengine: Introduce min burst length capability
dt-bindings: dma: dw: Add max burst transaction length property
dt-bindings: dma: dw: Convert DW DMAC to DT binding
dmaengine: ti: k3-udma: Query throughput level information from hardware
dmaengine: ti: k3-udma: Use defines for capabilities register parsing
dmaengine: xilinx: dpdma: Fix kerneldoc warning
dmaengine: xilinx: dpdma: add missing kernel doc
dmaengine: xilinx: dpdma: remove comparison of unsigned expression
...
There are DMA devices (like ours version of Synopsys DW DMAC) which have
DMA capabilities non-uniformly redistributed between the device channels.
In order to provide a way of exposing the channel-specific parameters to
the DMA engine consumers, we introduce a new DMA-device callback. In case
if provided it gets called from the dma_get_slave_caps() method and is
able to override the generic DMA-device capabilities.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723005848.31907-6-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Some devices may lack the support of the hardware accelerated SG list
entries automatic walking through and execution. In this case a burden of
the SG list traversal and DMA engine re-initialization lies on the
DMA engine driver (normally implemented by using a DMA transfer completion
IRQ to recharge the DMA device with a next SG list entry). But such
solution may not be suitable for some DMA consumers. In particular SPI
devices need both Tx and Rx DMA channels work synchronously in order
to avoid the Rx FIFO overflow. In case if Rx DMA channel is paused for
some time while the Tx DMA channel works implicitly pulling data into the
Rx FIFO, the later will be eventually overflown, which will cause the data
loss. So if SG list entries aren't automatically fetched by the DMA
engine, but are one-by-one manually selected for execution in the
ISRs/deferred work/etc., such problem will eventually happen due to the
non-deterministic latencies of the service execution.
In order to let the DMA consumer know about the DMA device capabilities
regarding the hardware accelerated SG list traversal we introduce the
max_sg_burst capability. It is supposed to be initialized by the DMA engine
driver with 0 if there is no limitation of the number of SG entries
atomically executed and with non-zero value if there is such constraints,
so the upper limit is determined by the number set to the property.
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723005848.31907-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Vinod Koul <vkoul@kernel.org>
DMA engines used with displays perform 2D interleaved transfers to read
framebuffers from memory and feed the data to the display engine. As the
same framebuffer can be displayed for multiple frames, the DMA
transactions need to be repeated until a new framebuffer replaces the
current one. This feature is implemented natively by some DMA engines
that have the ability to repeat transactions and switch to a new
transaction at the end of a transfer without any race condition or frame
loss.
This patch implements support for this feature in the DMA engine API. A
new DMA_PREP_REPEAT transaction flag allows DMA clients to instruct the
DMA channel to repeat the transaction automatically until one or more
new transactions are issued on the channel (or until all active DMA
transfers are explicitly terminated with the dmaengine_terminate_*()
functions). A new DMA_REPEAT transaction type is also added for DMA
engine drivers to report their support of the DMA_PREP_REPEAT flag.
A new DMA_PREP_LOAD_EOT transaction flag is also introduced (with a
corresponding DMA_LOAD_EOT capability bit), as requested during the
review of v4. The flag instructs the DMA channel that the transaction
being queued should replace the active repeated transaction when the
latter terminates (at End Of Transaction). Not setting the flag will
result in the active repeated transaction to continue being repeated,
and the new transaction being silently ignored.
The DMA_PREP_REPEAT flag is currently supported for interleaved
transactions only. Its usage can easily be extended to cover more
transaction types simply by adding an appropriate check in the
corresponding dmaengine_prep_*() function.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200717013337.24122-3-laurent.pinchart@ideasonboard.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The cookie tracking in dmaengine expects all submissions completed in
order. Some DMA devices like Intel DSA can complete submissions out of
order, especially if configured with a work queue sharing multiple DMA
engines. Add a status DMA_OUT_OF_ORDER that tx_status can be returned for
those DMA devices. The user should use callbacks to track the completion
rather than the DMA cookie. This would address the issue of dmatest
complaining that descriptors are "busy" when the cookie count goes
backwards due to out of order completion. Add DMA_COMPLETION_NO_ORDER
DMA capability to allow the driver to flag the device's ability to complete
operations out of order.
Reported-by: Swathi Kovvuri <swathi.kovvuri@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Swathi Kovvuri <swathi.kovvuri@intel.com>
Link: https://lore.kernel.org/r/158939557151.20335.12404113976045569870.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
When the channel register code was changed to allow hotplug operations,
dynamic indexing wasn't taken into account. When channels are randomly
plugged and unplugged out of order, the serial indexing breaks. Convert
channel indexing to using IDA tracking in order to allow dynamic
assignment. The previous code does not cause any regression bug for
existing channel allocation besides idxd driver since the hotplug usage
case is only used by idxd at this point.
With this change, the chan->idr_ref is also not needed any longer. We can
have a device with no channels registered due to hot plug. The channel
device release code no longer should attempt to free the dma device id on
the last channel release.
Fixes: e81274cd6b ("dmaengine: add support to dynamic register/unregister of channels")
Reported-by: Yixin Zhang <yixin.zhang@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Yixin Zhang <yixin.zhang@intel.com>
Link: https://lore.kernel.org/r/158679961260.7674.8485924270472851852.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
