This patch add max_burst to dma_get_slave_caps for clients
to get the burst capability of slave dma controller.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The two API function can cover most, if not all current APIs used to
request a channel. With minimal effort dmaengine drivers, platforms and
dmaengine user drivers can be converted to use the two function.
struct dma_chan *dma_request_chan_by_mask(const dma_cap_mask_t *mask);
To request any channel matching with the requested capabilities, can be
used to request channel for memcpy, memset, xor, etc where no hardware
synchronization is needed.
struct dma_chan *dma_request_chan(struct device *dev, const char *name);
To request a slave channel. The dma_request_chan() will try to find the
channel via DT, ACPI or in case if the kernel booted in non DT/ACPI mode
it will use a filter lookup table and retrieves the needed information from
the dma_slave_map provided by the DMA drivers.
This legacy mode needs changes in platform code, in dmaengine drivers and
finally the dmaengine user drivers can be converted:
For each dmaengine driver an array of DMA device, slave and the parameter
for the filter function needs to be added:
static const struct dma_slave_map da830_edma_map[] = {
{ "davinci-mcasp.0", "rx", EDMA_FILTER_PARAM(0, 0) },
{ "davinci-mcasp.0", "tx", EDMA_FILTER_PARAM(0, 1) },
{ "davinci-mcasp.1", "rx", EDMA_FILTER_PARAM(0, 2) },
{ "davinci-mcasp.1", "tx", EDMA_FILTER_PARAM(0, 3) },
{ "davinci-mcasp.2", "rx", EDMA_FILTER_PARAM(0, 4) },
{ "davinci-mcasp.2", "tx", EDMA_FILTER_PARAM(0, 5) },
{ "spi_davinci.0", "rx", EDMA_FILTER_PARAM(0, 14) },
{ "spi_davinci.0", "tx", EDMA_FILTER_PARAM(0, 15) },
{ "da830-mmc.0", "rx", EDMA_FILTER_PARAM(0, 16) },
{ "da830-mmc.0", "tx", EDMA_FILTER_PARAM(0, 17) },
{ "spi_davinci.1", "rx", EDMA_FILTER_PARAM(0, 18) },
{ "spi_davinci.1", "tx", EDMA_FILTER_PARAM(0, 19) },
};
This information is going to be needed by the dmaengine driver, so
modification to the platform_data is needed, and the driver map should be
added to the pdata of the DMA driver:
da8xx_edma0_pdata.slave_map = da830_edma_map;
da8xx_edma0_pdata.slavecnt = ARRAY_SIZE(da830_edma_map);
The DMA driver then needs to configure the needed device -> filter_fn
mapping before it registers with dma_async_device_register() :
ecc->dma_slave.filter_map.map = info->slave_map;
ecc->dma_slave.filter_map.mapcnt = info->slavecnt;
ecc->dma_slave.filter_map.fn = edma_filter_fn;
When neither DT or ACPI lookup is available the dma_request_chan() will
try to match the requester's device name with the filter_map's list of
device names, when a match found it will use the information from the
dma_slave_map to get the channel with the dma_get_channel() internal
function.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Channel matching with private_candidate() is used in two paths, the error
checking is slightly different in them and they are duplicating code also.
Move the code under find_candidate() to provide consistent execution and
going to allow us to reuse this mode of channel lookup later.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
In the current state, the capability of transfer reuse can neither be
set by a slave dmaengine driver, nor used by a client driver, because
the capability is not available to dma_get_slave_caps().
Fix this by adding a way to declare the capability.
Fixes: 272420214d ("dmaengine: Add DMA_CTRL_REUSE")
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The DMAengine API has a long standing race condition that is inherent to
the API itself. Calling dmaengine_terminate_all() is supposed to stop and
abort any pending or active transfers that have previously been submitted.
Unfortunately it is possible that this operation races against a currently
running (or with some drivers also scheduled) completion callback.
Since the API allows dmaengine_terminate_all() to be called from atomic
context as well as from within a completion callback it is not possible to
synchronize to the execution of the completion callback from within
dmaengine_terminate_all() itself.
This means that a user of the DMAengine API does not know when it is safe
to free resources used in the completion callback, which can result in a
use-after-free race condition.
This patch addresses the issue by introducing an explicit synchronization
primitive to the DMAengine API called dmaengine_synchronize().
The existing dmaengine_terminate_all() is deprecated in favor of
dmaengine_terminate_sync() and dmaengine_terminate_async(). The former
aborts all pending and active transfers and synchronizes to the current
context, meaning it will wait until all running completion callbacks have
finished. This means it is only possible to call this function from
non-atomic context. The later function does not synchronize, but can still
be used in atomic context or from within a complete callback. It has to be
followed up by dmaengine_synchronize() before a client can free the
resources used in a completion callback.
In addition to this the semantics of the device_terminate_all() callback
are slightly relaxed by this patch. It is now OK for a driver to only
schedule the termination of the active transfer, but does not necessarily
have to wait until the DMA controller has completely stopped. The driver
must ensure though that the controller has stopped and no longer accesses
any memory when the device_synchronize() callback returns.
This was in part done since most drivers do not pay attention to this
anyway at the moment and to emphasize that this needs to be done when the
device_synchronize() callback is implemented. But it also helps with
implementing support for devices where stopping the controller can require
operations that may sleep.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Pull dmaengine updates from Vinod Koul:
"This time we have a very typical update which is mostly fixes and
updates to drivers and no new drivers.
- the biggest change is coming from Peter for edma cleanup which even
caused some last minute regression, things seem settled now
- idma64 and dw updates
- iotdma updates
- module autoload fixes for various drivers
- scatter gather support for hdmac"
* tag 'dmaengine-4.4-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (77 commits)
dmaengine: edma: Add dummy driver skeleton for edma3-tptc
Revert "ARM: DTS: am33xx: Use the new DT bindings for the eDMA3"
Revert "ARM: DTS: am437x: Use the new DT bindings for the eDMA3"
dmaengine: dw: some Intel devices has no memcpy support
dmaengine: dw: platform: provide platform data for Intel
dmaengine: dw: don't override platform data with autocfg
dmaengine: hdmac: Add scatter-gathered memset support
dmaengine: hdmac: factorise memset descriptor allocation
dmaengine: virt-dma: Fix kernel-doc annotations
ARM: DTS: am437x: Use the new DT bindings for the eDMA3
ARM: DTS: am33xx: Use the new DT bindings for the eDMA3
dmaengine: edma: New device tree binding
dmaengine: Kconfig: edma: Select TI_DMA_CROSSBAR in case of ARCH_OMAP
dmaengine: ti-dma-crossbar: Add support for crossbar on AM33xx/AM43xx
dmaengine: edma: Merge the of parsing functions
dmaengine: edma: Do not allocate memory for edma_rsv_info in case of DT boot
dmaengine: edma: Refactor the dma device and channel struct initialization
dmaengine: edma: Get qDMA channel information from HW also
dmaengine: edma: Merge map_dmach_to_queue into assign_channel_eventq
dmaengine: edma: Correct PaRAM access function names (_parm_ to _param_)
...
dma_release_channel() decrements privatecnt counter and almost all dma_get*
function increments it with the exception of dma_get_slave_channel().
In most cases this does not cause issue since normally the channel is not
requested and released, but if a driver requests DMA channel via
dma_get_slave_channel() and releases the channel the privatecnt will be
unbalanced and this will prevent for example getting channel for memcpy.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This patch increments privatecnt value and set DMA_PRIVATE in device
caps in dma_request_slave_channel() function. This is needed to keep
privatecnt increment/decrement balance.
As function dma_release_channel() decrements privatecnt counter, we need
to increment it when channel is requested. Otherwise privatecnt drops
into negatives after few dma_release_channel() calls.
Reported-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Pull dmaengine updates from Vinod Koul:
"This time we have support for few new devices, few new features and
odd fixes spread thru the subsystem.
New devices added:
- support for CSRatlas7 dma controller
- Allwinner H3(sun8i) controller
- TI DMA crossbar driver on DRA7x
- new pxa driver
New features added:
- memset support is bought back now that we have a user in xdmac controller
- interleaved transfers support different source and destination strides
- supporting DMA routers and configuration thru DT
- support for reusing descriptors
- xdmac memset and interleaved transfer support
- hdmac support for interleaved transfers
- omap-dma support for memcpy
Others:
- Constify platform_device_id
- mv_xor fixes and improvements"
* tag 'dmaengine-4.2-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (46 commits)
dmaengine: xgene: fix file permission
dmaengine: fsl-edma: clear pending interrupts on initialization
dmaengine: xdmac: Add memset support
Documentation: dmaengine: document DMA_CTRL_ACK
dmaengine: virt-dma: don't always free descriptor upon completion
dmaengine: Revert "drivers/dma: remove unused support for MEMSET operations"
dmaengine: hdmac: Implement interleaved transfers
dmaengine: Move icg helpers to global header
dmaengine: mv_xor: improve descriptors list handling and reduce locking
dmaengine: mv_xor: Enlarge descriptor pool size
dmaengine: mv_xor: add support for a38x command in descriptor mode
dmaengine: mv_xor: Rename function for consistent naming
dmaengine: mv_xor: bug fix for racing condition in descriptors cleanup
dmaengine: pl330: fix wording in mcbufsz message
dmaengine: sirf: add CSRatlas7 SoC support
dmaengine: xgene-dma: Fix "incorrect type in assignement" warnings
dmaengine: fix kernel-doc documentation
dmaengine: pxa_dma: add support for legacy transition
dmaengine: pxa_dma: add debug information
dmaengine: pxa: add pxa dmaengine driver
...
Some drivers implement only pause operation (no resuming). Example is
pl330 where pause is needed for getting residuum. pl330 does not support
resume operation, transfer must be stopped after pause.
However for slaves this is exposed always as "pause and resume" which
introduces subtle errors on Odroid U3 board (Exynos4412 with pl330).
After adding pause function to pl330 driver the audio playback
(utilizing DMA) gets choppy after some time (approximately 24 hours).
Fix this by exposing "cmd_pause" if and only if pause and resume are
implemented.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reported-by: gabriel@unseen.is
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: <stable@vger.kernel.org>
Fixes: 88987d2c75 ("dmaengine: pl330: add DMA_PAUSE feature")
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
DMA routers are transparent devices used to mux DMA requests from
peripherals to DMA controllers. They are used when the SoC integrates more
devices with DMA requests then their controller can handle.
DRA7x is one example of such SoC, where the sDMA can hanlde 128 DMA request
lines, but in SoC level it has 205 DMA requests.
The of_dma_router will be registered as of_dma_controller with special
xlate function and additional parameters. The driver for the router is
responsible to craft the dma_spec (in the of_dma_route_allocate callback)
which can be used to requests a DMA channel from the real DMA controller.
This way the router can be transparent for the system while remaining generic
enough to be used in different environments.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Channels allocated via dma_get_any_slave_channel were not increasing
the counter tracking private allocations. When these channels were
released, privatecnt may erroneously fall to zero. The DMA device
would then lose its DMA_PRIVATE cap and fail to allocate future private
channels (via private_candidate) as any allocations still outstanding
would incorrectly be seen as public allocations.
Signed-off-by: Christopher Freeman <cfreeman@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This reverts commit ecc19d1786.
It added a new warning to try to encourage driver writers to set the
device capabities properly, but drivers haven't been updated and in the
meantime it just generaters a scary message that users cannot actually
do anything about.
Warnings like these are appropriate if you actually expect to fix the
code that causes them. They are not appropriate for releases.
Requested-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Free Software Foundation mailing address has been moved in the past and some
of the addresses here are outdated. Remove them from file headers since the
COPYING file in the kernel sources includes it.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Since commit 7bced39751 ("net_dma: simple removal") removed the net_dma
support entirely, net_dma_find_channel has no users left. Remove the function
entirely.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
For the slave caps retrieval to be really useful, most drivers need to
implement it.
Hence, we need to be slightly more aggressive, and trigger a warning at
registration time for drivers that don't fill their caps infos in order to
encourage them to implement it.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>