dma_transfer_direction is a normal enum. It means we can't usually use the
values as bit fields. Let's adjust this check and move it above the usage of
the direction parameter, due to the nature of the following usage of it.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The "else" keyword in the dw_dma_tasklet is removed as well. All together
simplifies the logic of the code and understanding of what is happening there.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Otherwise we get a warning in case of CONFIG_DMA_API_DEBUG=y
[ 45.775943] WARNING: at lib/dma-debug.c:933 check_unmap+0x5d6/0x6ac()
[ 45.782369] dw_dmac dw_dmac.0: DMA-API: device driver failed to check map error[device address=0x00000000356efcc0] [size=28 bytes] [mapped as single]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The patch allows to probe the device when platform data is absent and hardware
auto configuration is enabled. In that case the default platform data is used
where the channel allocation order is set to ascending, channel priority is set
to ascending, and private property is set to true.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Fix the following warnings when building with W=1 option:
drivers/dma/mxs-dma.c: In function 'mxs_dma_alloc_chan_resources':
drivers/dma/mxs-dma.c:368:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
drivers/dma/mxs-dma.c: In function 'mxs_dma_prep_slave_sg':
drivers/dma/mxs-dma.c:481:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
drivers/dma/mxs-dma.c:494:3: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
drivers/dma/mxs-dma.c:515:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
drivers/dma/mxs-dma.c: In function 'mxs_dma_prep_dma_cyclic':
drivers/dma/mxs-dma.c:563:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
NVIDIA's Tegra114 has APB DMA controller which has 32 dma channels
and support support channel wise pause control.
Add support for Tegra114 which uses the channel wise pause control
hardware feature.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
NVIDIA's some SoCs like Tegra114 support the channel wise pause control
inplace of global pause which pauses all DMA channels. When SoCs support
the channel wise pause control then it uses the global pause for clock
gating for register access as well as all DMA channel pause. Hence DMA
registers are not accessible if DMAs are globally paused on these new SoCs.
Add support for channel wise pause feature if SoCs support it.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
I was checking why this spinlock was never initialized, but it turns
out it's not used anywhere, so we can drop it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Dan Williams <djbw@fb.com>
When providers get blocked unregister_dca_providers() is called ending up
with dca_providers and dca_domain lists emptied. Dca should be prevented from
trying to unregister any provider if dca_domain list is found empty.
Cc: <stable@vger.kernel.org>
Reported-by: Jiang Liu <jiang.liu@huawei.com>
Tested-by: Gaohuai Han <hangaohuai@huawei.com>
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <djbw@fb.com>
The existing code set a value in the PCI_CHANERRMSK_INT register
for a workaround to address a pre-silicon bug on the Intel 5520 IO hub that
has been fixed when the hardware was released. There is no need for this
code.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <djbw@fb.com>
The PCI IDs for IvyBridge IOAT DMA needs to go into a header file since
dma_v3.c looks them up for certain hardware workarounds. Need to add to the
alignment workaround for IOAT 3.2 since it wasn't fixed in IVB.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <djbw@fb.com>
dmatest erroneously terminated transfers in normal cases also leading to
test failures for multiple threads over a channel. Fix this and
terminate transfers only in case of errors.
Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: Deepak Sikri <deepak.sikri@st.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
If dmaengine driver's .device_alloc_chan_resources() method returns -ENODEV,
dma_request_channel() will decide, that the driver has been removed and will
remove the device from its list. To prevent this use ENXIO if a slave lookup
fails.
Reported-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
device_control is an optional and not implemented in all DMA drivers.
Any calls to these will result in a NULL pointer dereference. dmatest
makes two of these calls when completing the kernel thread and removing
the module. These are corrected by calling the dmaengine_device_control
wrapper and checking for a non-existant device_control function pointer
there.
Signed-off-by: Jon Mason <jon.mason@intel.com>
CC: Vinod Koul <vinod.koul@intel.com>
CC: Dan Williams <djbw@fb.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
commit b14dab792dee(DMAEngine: Define interleaved transfer request api) adds
interleaved request api, this patch adds the dmaengine_prep_interleaved_dma
just like we have dmaengine_prep_ for other modes to avoid drivers call:
xxx_chan->device->device_prep_interleaved_dma().
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Cc: Jassi Brar <jaswinder.singh@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
In the current implementation of the OF DMA helpers, read-copy-update (RCU)
linked lists are being used for storing and accessing the DMA controller data.
This part of implementation is based upon V2 of the DMA helpers by Nicolas [1].
During a recent review of RCU, it became apparent that the code is missing the
required rcu_read_lock()/unlock() calls as well as synchronisation calls before
freeing any memory protected by RCU.
Having looked into adding the appropriate RCU calls to protect the DMA data it
became apparent that with the current DMA helper implementation, using RCU is
not as attractive as it may have been before. The main reasons being that ...
1. We need to protect the DMA data around calls to the xlate function.
2. The of_dma_simple_xlate() function calls the DMA engine function
dma_request_channel() which employs a mutex and so could sleep.
3. The RCU read-side critical sections must not sleep and so we cannot hold
an RCU read lock around the xlate function.
Therefore, instead of using RCU, an alternative for this use-case is to employ
a simple spinlock inconjunction with a usage count variable to keep track of
how many current users of the DMA data structure there are. With this
implementation, the DMA data cannot be freed until all current users of the
DMA data are finished.
This patch is based upon the DMA helpers fix for potential deadlock [2].
[1] http://article.gmane.org/gmane.linux.ports.arm.omap/73622
[2] http://marc.info/?l=linux-arm-kernel&m=134859982520984&w=2
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
In the latest version of the OF dma handlers I added support (rather hastily)
to exhaustively search for an available dma slave channel, for the use-case
where we have alternative slave channels that can be used. In the current
implementation a deadlock scenario can occur causing the CPU to loop forever.
The scenario is as follows ...
1. There are alternative channels avaialble
2. The first channel that is found by calling of_dma_find_channel() is not
available and so the call to the xlate function returns NULL. In this case
we will call of_dma_find_channel() again but we will return the same channel
that we found the first time and hence, again the xlate will return NULL and
we will loop here forever.
Fix this potential deadlock by just using a single for-loop and not a for-loop
nested in a do-while loop. This change also replaces the function
of_dma_find_channel() with of_dma_match_channel() which performs a simple check
to see if a DMA channel matches the name specified.
I have tested this implementation on an OMAP4 panda board by adding a dummy
DMA specifier, that will cause the xlate function to return NULL, to the
beginning of a list of DMA specifiers for a DMA client.
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <djbw@fb.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
DMA unmapping is handled by a driver so tell fsldma.c driver
(which is the DMA engine driver used by carma-fpga) to skip
unmapping destination and source buffers.
Cc: Ira W. Snyder <iws@ovro.caltech.edu>
Cc: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Dan Williams <djbw@fb.com>
dev_<level> calls take less code than dev_printk(KERN_<LEVEL>
and reducing object size is good.
Coalesce formats for easier grep.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
DMA Engine test module has module parameters to set the number of source
buffers for xor and pq operations. We can set these values larger than the
maximum number of sources that the device can support. These values are
not adjusted and the unsupported number of source buffers are passed to the
device. But most drivers don't check it, so unexpected results will happen.
This makes an appropriate adjustment for these module parameters before use.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <djbw@fb.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
vchan_dma_desc_free_list() iterates through each virt_dma_desc in the
specified list_head and calls vchan->desc_free().
We can use it instead of repeated execution of pl08x_desc_free() for each
virt_dma_desc in the list_head. Because vchan->desc_free callback is set
as pl08x_desc_free() for amba-pl08x driver.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <djbw@fb.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
This patch adds dw_dmac's platform data to DT node. It also creates slave info
node for SPEAr13xx, for the devices which were using dw_dmac.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
dw_dmac driver already supports device tree but it used to have its platform
data passed the non-DT way.
This patch does following changes:
- pass platform data via DT, non-DT way still takes precedence if both are used.
- create generic filter routine
- Earlier slave information was made available by slave specific filter routines
in chan->private field. Now, this information would be passed from within dmac
DT node. Slave drivers would now be required to pass bus_id (a string) as
parameter to this generic filter(), which would be compared against the slave
data passed from DT, by the generic filter routine.
- Update binding document
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[Fixed __devinit usage]
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
This config item has not carried much meaning for a while now and is
almost always enabled by default. As agreed during the Linux kernel
summit, remove it.
CC: Vinod Koul <vinod.koul@intel.com>
CC: Dan Williams <djbw@fb.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
