If we do
% echo 1 > /sys/module/dmatest/parameters/run
[ 115.851124] dmatest: Could not start test, no channels configured
% echo dma8chan7 > /sys/module/dmatest/parameters/channel
[ 127.563872] dmatest: Added 1 threads using dma8chan7
% cat /sys/module/dmatest/parameters/wait
... !!! HANG !!! ...
The culprit is the commit 6138f967bc
("dmaengine: dmatest: Use fixed point div to calculate iops")
which makes threads not to run, but pending and being kicked off by writing
to the 'run' node. However, it forgot to consider 'wait' routine to avoid
above mentioned case.
In order to fix this, check for really running threads, i.e. with pending
and done flags unset.
It's pity the culprit commit hadn't updated documentation and tested all
possible scenarios.
Fixes: 6138f967bc ("dmaengine: dmatest: Use fixed point div to calculate iops")
Cc: Seraj Alijan <seraj.alijan@sondrel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200428113518.70620-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Under some circumstances, i.e. when test is still running and about to
time out and user runs, for example,
grep -H . /sys/module/dmatest/parameters/*
the iterations parameter is not respected and test is going on and on until
user gives
echo 0 > /sys/module/dmatest/parameters/run
This is not what expected.
The history of this bug is interesting. I though that the commit
2d88ce76eb ("dmatest: add a 'wait' parameter")
is a culprit, but looking closer to the code I think it simple revealed the
broken logic from the day one, i.e. in the commit
0a2ff57d6f ("dmaengine: dmatest: add a maximum number of test iterations")
which adds iterations parameter.
So, to the point, the conditional of checking the thread to be stopped being
first part of conjunction logic prevents to check iterations. Thus, we have to
always check both conditions to be able to stop after given iterations.
Since it wasn't visible before second commit appeared, I add a respective
Fixes tag.
Fixes: 2d88ce76eb ("dmatest: add a 'wait' parameter")
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20200424161147.16895-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
DMA synchronization hook checks whether interrupt is raised by testing
corresponding bit in a hardware status register, and thus, clock should
be enabled in this case, otherwise CPU may hang if synchronization is
invoked while Runtime PM is in suspended state. This patch resumes the RPM
during of the DMA synchronization process in order to avoid potential
problems. It is a minor clean up of a previous commit, no real problem is
fixed by this patch because currently RPM is always in a resumed state
while DMA is synchronized, although this may change in the future.
Fixes: 6697255f23 ("dmaengine: tegra-apb: Improve DMA synchronization")
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20200426190835.21950-1-digetx@gmail.com
Signed-off-by: Vinod Koul <vkoul@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>
When a channel configuration fails, the status of the channel is set to
DEV_ERROR so that an attempt to submit it fails. However, this status
sticks until the heat end of the universe, making it impossible to
recover from the error.
Let's reset it when the channel is released so that further use of the
channel with correct configuration is not impacted.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Link: https://lore.kernel.org/r/20200419164912.670973-5-lkundrak@v3.sk
Signed-off-by: Vinod Koul <vkoul@kernel.org>
With an invalid dma_slave_config set previously,
mmp_tdma_prep_dma_cyclic() would detect an error whilst configuring the
channel, but proceed happily on:
[ 120.756530] mmp-tdma d42a0800.adma: mmp_tdma: unknown burst size.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Link: https://lore.kernel.org/r/20200419164912.670973-2-lkundrak@v3.sk
Signed-off-by: Vinod Koul <vkoul@kernel.org>
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>
If PCI_MSI is not set, building fais:
drivers/dma/hisi_dma.c: In function ‘hisi_dma_free_irq_vectors’:
drivers/dma/hisi_dma.c:138:2: error: implicit declaration of function ‘pci_free_irq_vectors’;
did you mean ‘pci_alloc_irq_vectors’? [-Werror=implicit-function-declaration]
pci_free_irq_vectors(data);
^~~~~~~~~~~~~~~~~~~~
Make HISI_DMA depends on PCI_MSI to fix this.
Fixes: e9f08b6525 ("dmaengine: hisilicon: Add Kunpeng DMA engine support")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20200328114133.17560-1-yuehaibing@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Pull dmaengine updates from Vinod Koul:
"Core:
- Some code cleanup and optimization in core by Andy
- Debugfs support for displaying dmaengine channels by Peter
Drivers:
- New driver for uniphier-xdmac controller
- Updates to stm32 dma, mdma and dmamux drivers and PM support
- More updates to idxd drivers
- Bunch of changes in tegra-apb driver and cleaning up of pm
functions
- Bunch of spelling fixes and Replace zero-length array patches
- Shutdown hook for fsl-dpaa2-qdma driver
- Support for interleaved transfers for ti-edma and virtualization
support for k3-dma driver
- Support for reset and updates in xilinx_dma driver
- Improvements and locking updates in at_hdma driver"
* tag 'dmaengine-5.7-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (89 commits)
dt-bindings: dma: renesas,usb-dmac: add r8a77961 support
dmaengine: uniphier-xdmac: Remove redandant error log for platform_get_irq
dmaengine: tegra-apb: Improve DMA synchronization
dmaengine: tegra-apb: Don't save/restore IRQ flags in interrupt handler
dmaengine: tegra-apb: mark PM functions as __maybe_unused
dmaengine: fix spelling mistake "exceds" -> "exceeds"
dmaengine: sprd: Set request pending flag when DMA controller is active
dmaengine: ppc4xx: Use scnprintf() for avoiding potential buffer overflow
dmaengine: idxd: remove global token limit check
dmaengine: idxd: reflect shadow copy of traffic class programming
dmaengine: idxd: Merge definition of dsa_batch_desc into dsa_hw_desc
dmaengine: Create debug directories for DMA devices
dmaengine: ti: k3-udma: Implement custom dbg_summary_show for debugfs
dmaengine: Add basic debugfs support
dmaengine: fsl-dpaa2-qdma: remove set but not used variable 'dpaa2_qdma'
dmaengine: ti: edma: fix null dereference because of a typo in pointer name
dmaengine: fsl-dpaa2-qdma: Adding shutdown hook
dmaengine: uniphier-xdmac: Add UniPhier external DMA controller driver
dt-bindings: dmaengine: Add UniPhier external DMA controller bindings
dmaengine: ti: k3-udma: Implement support for atype (for virtualization)
...
Boot CPU0 always handles DMA interrupts and under some rare circumstances
it could stuck in uninterruptible state for a significant time (like in a
case of KASAN + NFS root). In this case sibling CPU, which waits for DMA
transfer completion, will get a DMA transfer timeout. In order to handle
this rare condition, interrupt status needs to be polled until interrupt
is handled.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20200319212321.3297-2-digetx@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
When CONFIG_PM is disabled, gcc warning this:
drivers/dma/tegra20-apb-dma.c:1587:12: warning: 'tegra_dma_runtime_resume' defined but not used [-Wunused-function]
drivers/dma/tegra20-apb-dma.c:1578:12: warning: 'tegra_dma_runtime_suspend' defined but not used [-Wunused-function]
Make it as __maybe_unused to fix the warnings,
also remove unneeded function declarations.
Fixes: ec8a158678 ("dma: tegra: add dmaengine based dma driver")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200320071337.59756-1-yuehaibing@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
All but one error handling paths in the 'k3_udma_glue_cfg_rx_flow()'
function 'goto err' and call 'k3_udma_glue_release_rx_flow()'.
This not correct because this function has a 'channel->flows_ready--;' at
the end, but 'flows_ready' has not been incremented here, when we branch to
the error handling path.
In order to keep a correct value in 'flows_ready', un-roll
'k3_udma_glue_release_rx_flow()', simplify it, add some labels and branch
at the correct places when an error is detected.
Doing so, we also NULLify 'flow->udma_rflow' in a path that was lacking it.
Fixes: d702419134 ("dmaengine: ti: k3-udma: Add glue layer for non DMAengine user")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200318191209.1267-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>
On new Spreadtrum platforms, when the CPU enters idle, it will close
the DMA controllers' clock to save power if the DMA controller is not
busy. Moreover the DMA controller's busy signal depends on the DMA
enable flag and the request pending flag.
When DMA controller starts to transfer data, which means we already
set the DMA enable flag, but now we should also set the request pending
flag, in case the DMA clock will be closed accidentally if the CPU
can not detect the DMA controller's busy signal.
Signed-off-by: Zhenfang Wang <zhenfang.wang@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/02adbe4364ec436ec2c5bc8fd2386bab98edd884.1584019223.git.baolin.wang7@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Via the /sys/kernel/debug/dmaengine/summary users can get information
about the DMA devices and the used channels.
Example output on am654-evm with audio using two channels and after running
dmatest on 4 channels:
dma0 (285c0000.dma-controller): number of channels: 96
dma1 (31150000.dma-controller): number of channels: 267
dma1chan0 | 2b00000.mcasp:tx
dma1chan1 | 2b00000.mcasp:rx
dma1chan2 | in-use
dma1chan3 | in-use
dma1chan4 | in-use
dma1chan5 | in-use
For slave channels we can show the device and the channel name a given
channel is requested.
For non slave devices the only information we know is that the channel is
in use.
DMA drivers can implement the optional dbg_summary_show callback to
provide controller specific information instead of the generic one.
It is easy to extend the generic dmaengine_summary_show() to print
additional information about the used channels.
I have taken the idea from gpiolib and clk subsystems.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200306142839.17910-2-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This adds external DMA controller driver implemented in Socionext
UniPhier SoCs. This driver supports DMA_MEMCPY and DMA_SLAVE modes.
Since this driver does not support the the way to transfer size
unaligned to burst width, 'src_maxburst' or 'dst_maxburst' of
dma_slave_config must be 1 to transfer arbitrary size. If transfer
size is unaligned to burst size, the transfer isn't started and
the driver displays an error message.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Link: https://lore.kernel.org/r/1582271550-3403-3-git-send-email-hayashi.kunihiko@socionext.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The DT for virtualized hosts have dma-cells == 2 where the second parameter
is the ATYPE for the channel.
In case of dma-cells == 1 we can configure the ATYPE as 0 (reset value).
The ATYPE defined for j721e are:
0: pointers are physical addresses (no translation)
1: pointers are intermediate addresses (PVU)
2: pointers are virtual addresses (SMMU)
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200218143126.11361-3-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
It is enough to check whether hardware is busy on suspend and to reset
it across of suspend-resume because:
1. Channel's configuration is fully re-programmed on each DMA
transfer anyways.
2. Context save-restore of an active channel won't end up well without
pausing transfer prior to the context's saving, but note that every
channel shall be idling at the time of suspend, so save-restore is
not needed at all.
3. The only case where context save-restore may be useful is when
channel is in a paused state during suspend. But channel's pausing
could be supported only on Tegra114+ and this functionality wasn't
implemented by the driver for years now because there is no need for
it in upstream kernel.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20200209163356.6439-14-digetx@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
It's a bit impractical to enable hardware's clock at the time of DMA
channel's allocation because most of DMA client drivers allocate DMA
channel at the time of the driver's probing, and thus, DMA clock is kept
always-enabled in practice, defeating the whole purpose of runtime PM.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20200209163356.6439-13-digetx@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
There is no need to kill tasklet when driver's probe fails because tasklet
can't be scheduled at this time. It is also cleaner to kill tasklet on
channel's freeing rather than to kill it on driver's removal, otherwise
tasklet could perform a dummy execution after channel's releasing, which
isn't very nice.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20200209163356.6439-6-digetx@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>