A single AXIDMA controller can have one or two channels. When it has two
channels, the reset for both are tied together: resetting one channel
resets the other as well. This creates a problem where resetting one
channel will reset the registers for both channels, including clearing
interrupt enable bits for the other channel, which can then lead to
timeouts as the driver is waiting for an interrupt which never comes.
The driver currently has a probe-time work around for this: when a
channel is created, the driver also resets and enables the
interrupts. With two channels the reset for the second channel will
clear the interrupt enables for the first one. The work around in the
driver is just to manually enable the interrupts again in
xilinx_dma_alloc_chan_resources().
This workaround only addresses the probe-time issue. When channels are
reset at runtime (e.g., in xilinx_dma_terminate_all() or during error
recovery), there's no corresponding mechanism to restore the other
channel's interrupt enables. This leads to one channel having its
interrupts disabled while the driver expects them to work, causing
timeouts and DMA failures.
A proper fix is a complicated matter, as we should not reset the other
channel when it's operating normally. So, perhaps, there should be some
kind of synchronization for a common reset, which is not trivial to
implement. To add to the complexity, the driver also supports other DMA
types, like VDMA, CDMA and MCDMA, which don't have a shared reset.
However, when the two-channel AXIDMA is used in the (assumably) normal
use case, providing DMA for a single memory-to-memory device, the common
reset is a bit smaller issue: when something bad happens on one channel,
or when one channel is terminated, the assumption is that we also want
to terminate the other channel. And thus resetting both at the same time
is "ok".
With that line of thinking we can implement a bit better work around
than just the current probe time work around: let's enable the
AXIDMA interrupts at xilinx_dma_start_transfer() instead.
This ensures interrupts are enabled whenever a transfer starts,
regardless of any prior resets that may have cleared them.
This approach is also more logical: enable interrupts only when needed
for a transfer, rather than at resource allocation time, and, I think,
all the other DMA types should also use this model, but I'm reluctant to
do such changes as I cannot test them.
The reset function still enables interrupts even though it's not needed
for AXIDMA anymore, but it's common code for all DMA types (VDMA, CDMA,
MCDMA), so leave it unchanged to avoid affecting other variants.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Fixes: c0bba3a99f ("dmaengine: vdma: Add Support for Xilinx AXI Direct Memory Access Engine")
Link: https://patch.msgid.link/20260311-xilinx-dma-fix-v2-1-a725abb66e3c@ideasonboard.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The segment .control and .status fields both contain top bits which are
not part of the buffer size, the buffer size is located only in the bottom
max_buffer_len bits. To avoid interference from those top bits, mask out
the size using max_buffer_len first, and only then subtract the values.
Fixes: a575d0b4e6 ("dmaengine: xilinx_dma: Introduce xilinx_dma_get_residue")
Signed-off-by: Marek Vasut <marex@nabladev.com>
Link: https://patch.msgid.link/20260316222530.163815-1-marex@nabladev.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The cyclic DMA calculation is currently entirely broken and reports
residue only for the first segment. The problem is twofold.
First, when the first descriptor finishes, it is moved from active_list
to done_list, but it is never returned back into the active_list. The
xilinx_dma_tx_status() expects the descriptor to be in the active_list
to report any meaningful residue information, which never happens after
the first descriptor finishes. Fix this up in xilinx_dma_start_transfer()
and if the descriptor is cyclic, lift it from done_list and place it back
into active_list list.
Second, the segment .status fields of the descriptor remain dirty. Once
the DMA did one pass on the descriptor, the .status fields are populated
with data by the DMA, but the .status fields are not cleared before reuse
during the next cyclic DMA round. The xilinx_dma_get_residue() recognizes
that as if the descriptor was complete and had 0 residue, which is bogus.
Reinitialize the status field before placing the descriptor back into the
active_list.
Fixes: c0bba3a99f ("dmaengine: vdma: Add Support for Xilinx AXI Direct Memory Access Engine")
Signed-off-by: Marek Vasut <marex@nabladev.com>
Link: https://patch.msgid.link/20260316221943.160375-1-marex@nabladev.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Pull dmaengine updates from Vinod Koul:
"Core:
- Add Frank Li as susbstem reviewer to help with reviews
New Support:
- Mediatek support for Dimensity 6300 and 9200 controller
- Qualcomm Kaanapali and Glymur GPI DMA engine
- Synopsis DW AXI Agilex5
- Renesas RZ/V2N SoC
- Atmel microchip lan9691-dma
- Tegra ADMA tegra264
Updates:
- sg_nents_for_dma() helper use in subsystem
- pm_runtime_mark_last_busy() redundant call update for subsystem
- Residue support for xilinx AXIDMA driver
- Intel Max SGL Size Support and capabilities for DSA3.0
- AXI dma larger than 32bits address support"
* tag 'dmaengine-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (64 commits)
dmaengine: add Frank Li as reviewer
dt-bindings: dma: qcom,gpi: Update max interrupts lines to 16
dmaengine: fsl-edma: don't explicitly disable clocks in .remove()
dmaengine: xilinx: xdma: use sg_nents_for_dma() helper
dmaengine: sh: use sg_nents_for_dma() helper
dmaengine: sa11x0: use sg_nents_for_dma() helper
dmaengine: qcom: bam_dma: use sg_nents_for_dma() helper
dmaengine: qcom: adm: use sg_nents_for_dma() helper
dmaengine: pxa-dma: use sg_nents_for_dma() helper
dmaengine: lgm: use sg_nents_for_dma() helper
dmaengine: k3dma: use sg_nents_for_dma() helper
dmaengine: dw-axi-dmac: use sg_nents_for_dma() helper
dmaengine: bcm2835-dma: use sg_nents_for_dma() helper
dmaengine: axi-dmac: use sg_nents_for_dma() helper
dmaengine: altera-msgdma: use sg_nents_for_dma() helper
scatterlist: introduce sg_nents_for_dma() helper
dmaengine: idxd: Add Max SGL Size Support for DSA3.0
dmaengine: idxd: Expose DSA3.0 capabilities through sysfs
dmaengine: sh: rz-dmac: Make channel irq local
dmaengine: pl08x: Fix comment stating the difference between PL080 and PL081
...
The DMAEngine provides an interface for obtaining DMA transaction
descriptors from an array of scatter gather buffers represented by
struct dma_vec. This interface is used in the DMABUF API of the IIO
framework [1][2].
To enable DMABUF support through the IIO framework for the Xilinx DMA,
implement callback .device_prep_peripheral_dma_vec() of struct
dma_device in the driver.
[1]: 7a86d46998 ("iio: buffer-dmaengine: Support new DMABUF based userspace API")
[2]: 5878853fc9 ("dmaengine: Add API function dmaengine_prep_peripheral_dma_vec()")
Signed-off-by: Folker Schwesinger <dev@folker-schwesinger.de>
Reviewed-by: Suraj Gupta <suraj.gupta2@amd.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Link: https://lore.kernel.org/r/DCCKQLKOZC06.2H6LJ8RJQJNV2@folker-schwesinger.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Replace ternary (condition ? "enable" : "disable") syntax with helpers
from string_choices.h because:
1. Simple function call with one argument is easier to read. Ternary
operator has three arguments and with wrapping might lead to quite
long code.
2. Is slightly shorter thus also easier to read.
3. It brings uniformity in the text - same string.
4. Allows deduping by the linker, which results in a smaller binary
file.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> #dw-edma
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/20250114191021.854080-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
After commit 0edb555a65 ("platform: Make platform_driver::remove()
return void") .remove() is (again) the right callback to implement for
platform drivers.
Convert all platform drivers below drivers/dma after the previous
conversion commits apart from the wireless drivers to use .remove(),
with the eventual goal to drop struct platform_driver::remove_new(). As
.remove() and .remove_new() have the same prototypes, conversion is done
by just changing the structure member name in the driver initializer.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20241004062227.187726-2-u.kleine-koenig@baylibre.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() is renamed to .remove().
Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230919133207.1400430-58-u.kleine-koenig@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Program IRQDelay for AXI DMA. The interrupt timeout mechanism causes
the DMA engine to generate an interrupt after the delay time period
has expired. It enables dmaengine to respond in real-time even though
interrupt coalescing is configured. It also remove the placeholder
for delay interrupt and merge it with frame completion interrupt.
Since by default interrupt delay timeout is disabled this feature
addition has no functional impact on VDMA, MCDMA and CDMA IP's.
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Link: https://lore.kernel.org/r/1691387509-2113129-8-git-send-email-radhey.shyam.pandey@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Read DT property to check if AXI DMA is connected to streaming IP
i.e axiethernet. If connected i.e xlnx,axistream-connected property
is present in the dma node then pass AXI4-Stream control words to dma
client using metadata_ops dmaengine API.
If not connected then driver won't support metadata_ops dmaengine API
and continue to support all legacy usecases.
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Link: https://lore.kernel.org/r/1691387509-2113129-4-git-send-email-radhey.shyam.pandey@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230718143138.1066177-1-robh@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This was removed before due to the complete lack of users, but
3218910fd5 ("dmaengine: Add core function and capability check for
DMA_MEMCPY_SG") and 29cf37fa6d ("dmaengine: Add consumer for the new
DMA_MEMCPY_SG API function.") added it back despite still not having
any users whatsoever.
Fixes: 3218910fd5 ("dmaengine: Add core function and capability check for DMA_MEMCPY_SG")
Fixes: 29cf37fa6d ("dmaengine: Add consumer for the new DMA_MEMCPY_SG API function.")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/20220606074733.622616-1-hch@lst.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Handle errors when trying to map the IRQ for the DMA channels.
The main motivation here is to be able to handle probe deferral. E.g. when
using DT overlays it is possible that the DMA controller is probed before
interrupt controller, depending on the order in the DT.
In order to support this switch from irq_of_parse_and_map() to
of_irq_get(), which internally does the same, but it will return
EPROBE_DEFER when the interrupt controller is not yet available.
As a result other errors, such as an invalid IRQ specification, or missing
IRQ are also properly handled.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/20211208114212.234130-1-lars@metafoo.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
DMA clients can provide one of two types of callbacks. For this reason
dmaengine drivers should not directly invoke `callback`, but always use
`dmaengine_desc_callback_invoke()`. This makes sure that both types of
callbacks are handled correctly.
The xilinx_dma driver currently doesn't do this for cyclic descriptors and
only handles the `callback` type callback. If the client used the
`callback_result` type callback it will not be called.
Fix this by switching to `dmaengine_desc_callback_valid()` and
`dmaengine_desc_callback_invoke()`.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20211025075428.2094-2-lars@metafoo.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Modify the prototype from xilinx_dma_tx_descriptor to
xilinx_dma_alloc_tx_descriptor and xilinx_dma_channel_set_config
to xilinx_vdma_channel_set_config in API description to
fix below linux kernel-doc warnings.
drivers/dma/xilinx/xilinx_dma.c:800: warning: expecting
prototype for xilinx_dma_tx_descriptor(). Prototype was
for xilinx_dma_alloc_tx_descriptor() instead.
drivers/dma/xilinx/xilinx_dma.c:2471: warning: expecting
prototype for xilinx_dma_channel_set_config(). Prototype
was for xilinx_vdma_channel_set_config() instead.
Signed-off-by: Shravya Kumbham <shravya.kumbham@xilinx.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1631525316-2323-1-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The xilinx dma driver uses the consistent allocations, so for correct
operation also set the DMA mask for coherent APIs. It fixes the below
kernel crash with dmatest client when DMA IP is configured with 64-bit
address width and linux is booted from high (>4GB) memory.
Call trace:
[ 489.531257] dma_alloc_from_pool+0x8c/0x1c0
[ 489.535431] dma_direct_alloc+0x284/0x330
[ 489.539432] dma_alloc_attrs+0x80/0xf0
[ 489.543174] dma_pool_alloc+0x160/0x2c0
[ 489.547003] xilinx_cdma_prep_memcpy+0xa4/0x180
[ 489.551524] dmatest_func+0x3cc/0x114c
[ 489.555266] kthread+0x124/0x130
[ 489.558486] ret_from_fork+0x10/0x3c
[ 489.562051] ---[ end trace 248625b2d596a90a ]---
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Reviewed-by: Harini Katakam <harini.katakam@xilinx.com>
Link: https://lore.kernel.org/r/1629363528-30347-1-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
When user calls dmaengine_terminate_sync, the driver will clean up any
remaining descriptors for all the pending or active transfers that had
previously been submitted. However, this might happen whilst the tasklet is
invoking the DMA callback for the last finished transfer, so by the time it
returns and takes over the channel's spinlock, the list of completed
descriptors it was traversing is no longer valid. This leads to a
read-after-free situation.
Fix it by signalling whether a user-triggered termination has happened by
means of a boolean variable.
Signed-off-by: Adrian Larumbe <adrian.martinezlarumbe@imgtec.com>
Link: https://lore.kernel.org/r/20210706234338.7696-3-adrian.martinezlarumbe@imgtec.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The Xilinx dmaengine driver uses a tasklet to process completed
descriptors and execute their callbacks.
Currently consumers of the DMA channel have to no method of synchronization
against this tasklet when using the Xilinx dmaengine drivers. This can lead
to race conditions when the consumer frees resources that are accessed in
the callback before the tasklet has finished running.
It is not enough to just call dmaengine_terminal_all() since on a
multi-processor system the tasklet can run concurrently to it and might
call the callback after dmaengine_terminate_all() has already finished.
To mitigate this issue implement the synchronize() callback for the driver,
which will wait until the tasklet has finished.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20210313125311.4823-1-lars@metafoo.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
