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This patch adds support for the DMA engine present on Allwinner A10,
A13, A10S and A20 SoCs. This engine has two kinds of channels: normal
and dedicated. The main difference is in the mode of operation;
while a single normal channel may be operating at any given time,
dedicated channels may operate simultaneously provided there is no
overlap of source or destination.
Hardware documentation can be found on A10 User Manual (section 12), A13
User Manual (section 14) and A20 User Manual (section 1.12)
Signed-off-by: Emilio López <emilio@elopez.com.ar>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Due to how async_tx behaves internally, having more XOR channels than
CPUs is actually hurting performance more than it improves it, because
memcpy requests get scheduled on a different channel than the XOR
requests, but async_tx will still wait for the completion of the
memcpy requests before scheduling the XOR requests.
It is in fact more efficient to have at most one channel per CPU,
which this patch implements by limiting the number of channels per
engine, and the number of engines registered depending on the number
of availables CPUs.
Marvell platforms are currently available in one CPU, two CPUs and
four CPUs configurations:
- in the configurations with one CPU, only one channel from one
engine is used.
- in the configurations with two CPUs, only one channel from each
engine is used (they are two XOR engines)
- in the configurations with four CPUs, both channels of both engines
are used.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The only reason why we had dmacap,* properties is because back when
DMA_MEMSET was supported, only one out of the two channels per engine
could do a memset operation. But this is something that the driver
already knows anyway, and since then, the DMA_MEMSET support has been
removed.
The driver is already well aware of what each channel supports and the
one to one mapping between Linux specific implementation details (such
as dmacap,interrupt enabling DMA_INTERRUPT) and DT properties is a
good indication that these DT properties are wrong.
Therefore, this commit simply gets rid of these dmacap,* properties,
they are now ignored, and the driver is responsible for knowing the
capabilities of the hardware with regard to the dmaengine subsystem
expectations.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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When there is only one burst required do not emit loop instructions to
loop exactly once. Emit just the body of the loop.
Signed-off-by: Michal Suchanek <hramrach@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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set_irq_flags is ARM specific with custom flags which have genirq
equivalents. Convert drivers to use the genirq interfaces directly, so we
can kill off set_irq_flags. The translation of flags is as follows:
IRQF_VALID -> !IRQ_NOREQUEST
IRQF_PROBE -> !IRQ_NOPROBE
IRQF_NOAUTOEN -> IRQ_NOAUTOEN
For IRQs managed by an irqdomain, the irqdomain core code handles clearing
and setting IRQ_NOREQUEST already, so there is no need to do this in
.map() functions and we can simply remove the set_irq_flags calls. Some
users also modify IRQ_NOPROBE and this has been maintained although it
is not clear that is really needed. There appears to be a great deal of
blind copy and paste of this code.
Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The new Solo X has more requirements for SDMA events. So it creates
a event mux to remap most of event numbers in GPR (General Purpose
Register). If we want to use SDMA support for those module who do
not get the even number as default, we need to configure GPR first.
Thus this patch adds this support of GPR event remapping configuration
to the SDMA driver.
Signed-off-by: Zidan Wang <zidan.wang@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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In cyclic mode, the round chaining has been broken by the introduction
of at_xdmac_queue_desc(): AT_XDMAC_MBR_UBC_NDE is set for all descriptors
excepted for the last one. at_xdmac_queue_desc() has to be called one
more time to chain the last and the first descriptors.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: 0d0ee751f7f7 ("dmaengine: xdmac: Rework the chaining logic")
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Tasklets may have been scheduled as a result of an earlier interrupt
that could still be running. Kill them before unregistering the
device.
Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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We must explicitly free the IRQ before the device is unregistered in
case any device interrupt still occurs, so there's no point in using
the managed variations of the IRQ functions. Change to the regular
versions.
Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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When scanning for a free DMA channel, the filter function should ensure
that the channel is on the controller that it was requested to be on in
the DT.
Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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When the DT requests a specific channel to use it is not necesssary
to scan through all DMA channels in the system. Just return the
requested channel using dma_get_slave_channel().
Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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There are a some signedness bugs such as testing for < 0 on unsigned
return values. Additionally there are some cases where functions which
should return NULL on error actually return a PTR_ERR value which can
result in oopses on error. Fix these issues.
Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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For some reason the controller does not support 8 byte transfers (but
does support all other powers of 2 up to 128). In this case fall back
to 4 bytes. In addition, fall back to 128 bytes when any larger power
of 2 would be possible within the alignment constraints, as this is
the maximum supported.
It makes no sense to outright reject 8 or >128 bytes just because the
alignment constraints make those the maximum possible size given the
parameters for the transaction. For instance, this can result in a DMA
from/to an 8 byte aligned address failing.
It is perfectly safe to fall back to smaller transfer sizes, the only
consequence is reduced transfer efficiency, which is far better than
not allowing the transfer at all.
Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Several function prototypes did not match the dmaengine API they were
implementing, resulting in build warnings. Correct these.
Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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If DMA interrupt comes and is latched by IRQ controller during the
execution of dma_terminate_all(), dma_irq routine will be executed
after dma terminated, and it will cause kernel panic.
We clear DMA interrupts in dma_terminate_all() to avoid this useless
interrupt.
Signed-off-by: Yanchang Li <Yanchang.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Add support for DMA on NXP LPC18xx/43xx platforms which has
a multiplexer in front of the PL080 dma request lines.
The mux is a single register in the LPC18xx/43xx CREG block
and can multiplex up to 4 request lines to each of the 16
lines on the PL080.
Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Add support for assigning DMA channels from a device tree.
[je: remove channel sub-node parsing, dynamic channel creation on xlate]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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This fixes the following error:
drivers/dma/pxa_dma.c: In function ‘dbg_show_requester_chan’:
drivers/dma/pxa_dma.c:192:2: error: void value not ignored as it ought to be
pos += seq_printf(s, "DMA channel %d requester :\n", phy->idx);
^
drivers/dma/pxa_dma.c:197:8: error: void value not ignored as it ought to be
!!(drcmr & DRCMR_MAPVLD));
^
scripts/Makefile.build:258: recipe for target 'drivers/dma/pxa_dma.o' failed
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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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>
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Don't use the direction passed in the configuration, and rely on each
transfer's direction to prepare the transfers. This will enable
future removal of direction parameter from dma_slave_config.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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IOAT_COMPLETION_PENDING flag was deprecated for v2 and v3 drivers but was
not cleaned up. Doing that now. The commit deprecated this flag was
4dec23d7 ioatdma: fix race between updating ioat->head and
IOAT_COMPLETION_PENDING.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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./scripts/kerne-doc is reporting errors on dma.h. Clean up all reported
errors.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Since we are a "single" device driver now we no longer require the function
pointers in ioatdma_device. Remove.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Moving the relevant functions to their respective .c files and removal of
dma_v3.c file. Also removed various ioat3 references when appropriate.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Move all DMA descriptor prepping functions to prep.c file. Fixup all
broken bits caused by the move.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Moving all the init routines to init.c and fixup anything broken during
the move.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Move and fixup all sysfs related bits to sysfs.c file.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Clean out dma_v2 and remove ioat2 calls since we are moving everything
to just ioat.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Changing the variable names for ioatdma_device to be consistently named
ioat_dma instead of device/dma in order to avoid confusion and distinct
from struct device. This will clearly indicate that it is an
ioatdma_device. This also make all the naming consistent that the dma
device is ioat_dma and all the channels are ioat_chan.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Kill the common ioatdma channel structure and everything that is not
dma_chan to be ioat_dma_chan. Since we don't have to worry about v1
and v2 ioatdma anymore this makes it much cleaner and obvious for
maintenance.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Removal of support for ioatdma v2 device support.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Cleaning up of ioat1 specific code as it is no longer supported
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Removal of any devices that are ioatdma pre-3.0. This is the first step
in attempting to clean up the ioatdma driver and remove hw no longer
supported.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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If the allocation order is 16, then the u16 count will overflow and wrap
to zero when assigned the value 1 << 16.
Change the type of 'total_descs' to int, so that it is large enough to
store a value equal or greater than 1 << 16.
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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If the allocation order is 16, then the u16 index will overflow and wrap
to zero instead of being equal or greater than 1 << 16. The loop
condition will always be true, and the loop will run until all the
memory resources are depleted.
Change the type of index 'i' to u32, so that it is large enough to store
a value equal or greater than 1 << 16.
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The functions irq_irq_err and ipu_irq_fn are identical plus/minus the
comments. Remove one.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The irq argument of most interrupt flow handlers is unused or merily
used instead of a local variable. The handlers which need the irq
argument can retrieve the irq number from the irq descriptor.
Search and update was done with coccinelle and the invaluable help of
Julia Lawall.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The XDMAC also supports memset operations over discontiguous areas. Add the
necessary logic to support this.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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DMA will not stop when clearing enable bit till all transaction
is done. The bug is exposed in audio playback because ring DMA
chain never stop. Force hardware to stop with setting FORCE bit.
Signed-off-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Align src and dst width to fix data alignment issue as
trailing single transaction that does not fill a full
burst require identical src/dst data width.
Burst length limitation can be addressed well too.
Signed-off-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Most drivers need to set constraints on the buffer alignment for async tx
operations. However, even though it is documented, some drivers either use
a defined constant that is not matching what the alignment variable expects
(like DMA_BUSWIDTH_* constants) or fill the alignment in bytes instead of
power of two.
Add a new enum for these alignments that matches what the framework
expects, and convert the drivers to it.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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devm_ioremap_resource returns ERR_PTR on failure.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Support cyclic dma for audio playback
Signed-off-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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This patch adds DEV_TO_DEV support for i.MX SDMA driver to support data
transfer between two peripheral FIFOs.
The per_2_per script requires two peripheral addresses and two DMA
requests, and it need to check the src addr and dst addr is in the SPBA
bus space or in the AIPS bus space.
Signed-off-by: Shengjiu Wang <shengjiu.wang@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine fixes from Vinod Koul:
"We had a regression due to reuse of descriptor so we have reverted
that.
The rest are driver fixes:
- at_hdmac and at_xdmac for residue, trannfer width, and channel config
- pl330 final fix for dma fails and overflow issue
- xgene resouce map fix
- mv_xor big endian op fix"
* tag 'dmaengine-fix-4.2-rc5' of git://git.infradead.org/users/vkoul/slave-dma:
Revert "dmaengine: virt-dma: don't always free descriptor upon completion"
dmaengine: mv_xor: fix big endian operation in register mode
dmaengine: xgene-dma: Fix the resource map to handle overlapping
dmaengine: at_xdmac: fix transfer data width in at_xdmac_prep_slave_sg()
dmaengine: at_hdmac: fix residue computation
dmaengine: at_xdmac: fix bug about channel configuration
dmaengine: pl330: Really fix choppy sound because of wrong residue calculation
dmaengine: pl330: Fix overflow when reporting residue in memcpy
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This reverts commit b9855f03d560d351e95301b9de0bc3cad3b31fe9.
The patch break existing DMA usage case. For example, audio SOC
dmaengine never release channel and cause virt-dma to cache too
much memory in descriptor to exhaust system memory.
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Commit 6f166312c6ea2 ("dmaengine: mv_xor: add support for a38x command
in descriptor mode") introduced the support for a feature that
appeared in Armada 38x: specifying the operation to be performed in a
per-descriptor basis rather than globally per channel.
However, when doing so, it changed the function mv_chan_set_mode() to
use:
if (IS_ENABLED(__BIG_ENDIAN))
instead of:
#if defined(__BIG_ENDIAN)
While IS_ENABLED() is perfectly fine for CONFIG_* symbols, it is not
for other symbols such as __BIG_ENDIAN that is provided directly by
the compiler. Consequently, the commit broke support for big-endian,
as the XOR_DESCRIPTOR_SWAP flag was not set in the XOR channel
configuration register.
The primarily visible effect was some nasty warnings and failures
appearing during the self-test of the XOR unit:
[ 1.197368] mv_xor d0060900.xor: error on chan 0. intr cause 0x00000082
[ 1.197393] mv_xor d0060900.xor: config 0x00008440
[ 1.197410] mv_xor d0060900.xor: activation 0x00000000
[ 1.197427] mv_xor d0060900.xor: intr cause 0x00000082
[ 1.197443] mv_xor d0060900.xor: intr mask 0x000003f7
[ 1.197460] mv_xor d0060900.xor: error cause 0x00000000
[ 1.197477] mv_xor d0060900.xor: error addr 0x00000000
[ 1.197491] ------------[ cut here ]------------
[ 1.197513] WARNING: CPU: 0 PID: 1 at ../drivers/dma/mv_xor.c:664 mv_xor_interrupt_handler+0x14c/0x170()
See also:
http://storage.kernelci.org/next/next-20150617/arm-mvebu_v7_defconfig+CONFIG_CPU_BIG_ENDIAN=y/lab-khilman/boot-armada-xp-openblocks-ax3-4.txt
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Fixes: 6f166312c6ea2 ("dmaengine: mv_xor: add support for a38x command in descriptor mode")
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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There is an overlap in dma ring cmd csr region due to sharing of ethernet
ring cmd csr region. This patch fix the resource overlapping by mapping
the entire dma ring cmd csr region.
Signed-off-by: Rameshwar Prasad Sahu <rsahu@apm.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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This patch adds the missing update of the transfer data width in
at_xdmac_prep_slave_sg().
Indeed, for each item in the scatter-gather list, we check whether the
transfer length is aligned with the data width provided by
dmaengine_slave_config(). If so, we directly use this data width for the
current part of the transfer we are preparing. Otherwise, the data width
is reduced to 8 bits (1 byte). Of course, the actual number of register
accesses must also be updated to match the new data width.
So one chunk was missing in the original patch (see Fixes tag below): the
number of register accesses was correctly set to (len >> fixed_dwidth) in
mbr_ubc but the real data width was not updated in mbr_cfg. Since mbr_cfg
may change for each part of the scatter-gather transfer this also explains
why the original patch used the Descriptor View 2 instead of the
Descriptor View 1.
Let's take the example of a DMA transfer to write 8bit data into an Atmel
USART with FIFOs. When FIFOs are enabled in the USART, its Transmit
Holding Register (THR) works in multidata mode, that is to say that up to
4 8bit data can be written into the THR in a single 32bit access and it is
still possible to write only one data with a 8bit access. To take
advantage of this new feature, the DMA driver was modified to allow
multiple dwidths when doing slave transfers.
For instance, when the total length is 22 bytes, the USART driver splits
the transfer into 2 parts:
First part: 20 bytes transferred through 5 32bit writes into THR
Second part: 2 bytes transferred though 2 8bit writes into THR
For the second part, the data width was first set to 4_BYTES by the USART
driver thanks to dmaengine_slave_config() then at_xdmac_prep_slave_sg()
reduces this data width to 1_BYTE because the 2 byte length is not aligned
with the original 4_BYTES data width. Since the data width is modified,
the actual number of writes into THR must be set accordingly.
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Fixes: 6d3a7d9e3ada ("dmaengine: at_xdmac: allow muliple dwidths when doing slave transfers")
Cc: stable@vger.kernel.org #4.0 and later
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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