Commit Graph

3823 Commits

Author SHA1 Message Date
Alexander.Barabash@dell.com
10d55ea613 ioat: ioat_alloc_ring() failure handling.
[ Upstream commit b0b5ce1010 ]

If dma_alloc_coherent() returns NULL in ioat_alloc_ring(), ring
allocation must not proceed.

Until now, if the first call to dma_alloc_coherent() in
ioat_alloc_ring() returned NULL, the processing could proceed, failing
with NULL-pointer dereferencing further down the line.

Signed-off-by: Alexander Barabash <alexander.barabash@dell.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/75e9c0e84c3345d693c606c64f8b9ab5@x13pwhopdag1307.AMER.DELL.COM
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-17 19:47:16 +01:00
John Stultz
64f2737186 dmaengine: k3dma: Avoid null pointer traversal
[ Upstream commit 2f42e05b94 ]

In some cases we seem to submit two transactions in a row, which
causes us to lose track of the first. If we then cancel the
request, we may still get an interrupt, which traverses a null
ds_run value.

So try to avoid starting a new transaction if the ds_run value
is set.

While this patch avoids the null pointer crash, I've had some
reports of the k3dma driver still getting confused, which
suggests the ds_run/ds_done value handling still isn't quite
right. However, I've not run into an issue recently with it
so I think this patch is worth pushing upstream to avoid the
crash.

Signed-off-by: John Stultz <john.stultz@linaro.org>
[add ss tag]
Link: https://lore.kernel.org/r/20191218190906.6641-1-john.stultz@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-17 19:47:16 +01:00
Nicholas Graumann
c4986e4734 dmaengine: xilinx_dma: Clear desc_pendingcount in xilinx_dma_reset
[ Upstream commit 8a631a5a0f ]

Whenever we reset the channel, we need to clear desc_pendingcount
along with desc_submitcount. Otherwise when a new transaction is
submitted, the irq coalesce level could be programmed to an incorrect
value in the axidma case.

This behavior can be observed when terminating pending transactions
with xilinx_dma_terminate_all() and then submitting new transactions
without releasing and requesting the channel.

Signed-off-by: Nicholas Graumann <nick.graumann@gmail.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1571150904-3988-8-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-04 19:12:38 +01:00
Christian Lamparter
c2160296f1 dmaengine: dw-dmac: implement dma protection control setting
[ Upstream commit 7b0c03ecc4 ]

This patch adds a new device-tree property that allows to
specify the dma protection control bits for the all of the
DMA controller's channel uniformly.

Setting the "correct" bits can have a huge impact on the
PPC460EX and APM82181 that use this DMA engine in combination
with a DesignWare' SATA-II core (sata_dwc_460ex driver).

In the OpenWrt Forum, the user takimata reported that:
|It seems your patch unleashed the full power of the SATA port.
|Where I was previously hitting a really hard limit at around
|82 MB/s for reading and 27 MB/s for writing, I am now getting this:
|
|root@OpenWrt:/mnt# time dd if=/dev/zero of=tempfile bs=1M count=1024
|1024+0 records in
|1024+0 records out
|real    0m 13.65s
|user    0m 0.01s
|sys     0m 11.89s
|
|root@OpenWrt:/mnt# time dd if=tempfile of=/dev/null bs=1M count=1024
|1024+0 records in
|1024+0 records out
|real    0m 8.41s
|user    0m 0.01s
|sys     0m 4.70s
|
|This means: 121 MB/s reading and 75 MB/s writing!
|
|The drive is a WD Green WD10EARX taken from an older MBL Single.
|I repeated the test a few times with even larger files to rule out
|any caching, I'm still seeing the same great performance. OpenWrt is
|now completely on par with the original MBL firmware's performance.

Another user And.short reported:
|I can report that your fix worked! Boots up fine with two
|drives even with more partitions, and no more reboot on
|concurrent disk access!

A closer look into the sata_dwc_460ex code revealed that
the driver did initally set the correct protection control
bits. However, this feature was lost when the sata_dwc_460ex
driver was converted to the generic DMA driver framework.

BugLink: https://forum.openwrt.org/t/wd-mybook-live-duo-two-disks/16195/55
BugLink: https://forum.openwrt.org/t/wd-mybook-live-duo-two-disks/16195/50
Fixes: 8b3444852a ("sata_dwc_460ex: move to generic DMA driver")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-13 08:51:43 +01:00
Vinod Koul
cffba72c1a dmaengine: coh901318: Remove unused variable
commit 35faaf0df4 upstream.

Commit 627469e444 ("dmaengine: coh901318: Fix a double-lock bug") left
flags variable unused, so remove it to fix the warning.

drivers/dma/coh901318.c: In function 'coh901318_config':
drivers/dma/coh901318.c:1805:16: warning: unused variable 'flags' [-Wunused-variable]
  unsigned long flags;
                ^~~~~

Fixes: 627469e444 ("dmaengine: coh901318: Fix a double-lock bug")
Reported-By: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-13 08:51:42 +01:00
Jia-Ju Bai
213ca8b833 dmaengine: coh901318: Fix a double-lock bug
[ Upstream commit 627469e444 ]

The function coh901318_alloc_chan_resources() calls spin_lock_irqsave()
before calling coh901318_config().
But coh901318_config() calls spin_lock_irqsave() again in its
definition, which may cause a double-lock bug.

Because coh901318_config() is only called by
coh901318_alloc_chan_resources(), the bug fix is to remove the
calls to spin-lock and -unlock functions in coh901318_config().

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-13 08:51:41 +01:00
Pierre-Yves MORDRET
ecda0abb14 dmaengine: stm32-dma: check whether length is aligned on FIFO threshold
commit cc832dc8e3 upstream.

When a period length is not multiple of FIFO some data may be stuck
within FIFO.

Burst/FIFO Threshold/Period or buffer length check has to be hardened

In any case DMA will grant any request from client but will degraded
any parameters whether awkward.

Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-05 09:21:35 +01:00
Wolfram Sang
fef30612e2 dmaengine: rcar-dmac: set scatter/gather max segment size
[ Upstream commit 97d49c59e2 ]

Fix warning when running with CONFIG_DMA_API_DEBUG_SG=y by allocating a
device_dma_parameters structure and filling in the max segment size.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-24 08:20:30 +01:00
Rami Rosen
47dd538e9c dmaengine: ioat: fix prototype of ioat_enumerate_channels
[ Upstream commit f4d34aa8c8 ]

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-24 08:20:24 +01:00
Nathan Chancellor
ae3765a0a3 dmaengine: timb_dma: Use proper enum in td_prep_slave_sg
[ Upstream commit 5e621f5d53 ]

Clang warns when implicitly converting from one enumerated type to
another. Avoid this by using the equivalent value from the expected
type.

drivers/dma/timb_dma.c:548:27: warning: implicit conversion from
enumeration type 'enum dma_transfer_direction' to different enumeration
type 'enum dma_data_direction' [-Wenum-conversion]
                td_desc->desc_list_len, DMA_MEM_TO_DEV);
                                        ^~~~~~~~~~~~~~
1 warning generated.

Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-24 08:19:46 +01:00
Dan Carpenter
8edddc2cf3 dmaengine: at_xdmac: remove a stray bottom half unlock
[ Upstream commit 0b515abb6b ]

We switched this code from spin_lock_bh() to vanilla spin_lock() but
there was one stray spin_unlock_bh() that was overlooked.  This
patch converts it to spin_unlock() as well.

Fixes: d8570d018f ("dmaengine: at_xdmac: move spin_lock_bh to spin_lock in tasklet")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20 18:46:20 +01:00
Daniel Silsby
fc7be63083 dmaengine: dma-jz4780: Further residue status fix
[ Upstream commit 83ef4fb755 ]

Func jz4780_dma_desc_residue() expects the index to the next hw
descriptor as its last parameter. Caller func jz4780_dma_tx_status(),
however, applied modulus before passing it. When the current hw
descriptor was last in the list, the index passed became zero.

The resulting excess of reported residue especially caused problems
with cyclic DMA transfer clients, i.e. ALSA AIC audio output, which
rely on this for determining current DMA location within buffer.

Combined with the recent and related residue-reporting fixes, spurious
ALSA audio underruns on jz4770 hardware are now fixed.

Signed-off-by: Daniel Silsby <dansilsby@gmail.com>
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20 18:46:17 +01:00
Paul Cercueil
f6d4561cae dmaengine: dma-jz4780: Don't depend on MACH_JZ4780
[ Upstream commit c558ecd21c ]

If we make this driver depend on MACH_JZ4780, that means it can be
enabled only if we're building a kernel specially crafted for a
JZ4780-based board, while most GNU/Linux distributions will want one
generic MIPS kernel that works on multiple boards.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20 18:46:16 +01:00
Baolin Wang
113a154ef2 dmaengine: sprd: Fix the possible memory leak issue
[ Upstream commit ec1ac30959 ]

If we terminate the channel to free all descriptors associated with this
channel, we will leak the memory of current descriptor if the current
descriptor is not completed, since it had been deteled from the desc_issued
list and have not been added into the desc_completed list.

Thus we should check if current descriptor is completed or not, when freeing
the descriptors associated with one channel, if not, we should free it to
avoid this issue.

Fixes: 9b3b8171f7 ("dmaengine: sprd: Add Spreadtrum DMA driver")
Reported-by: Zhenfang Wang <zhenfang.wang@unisoc.com>
Tested-by: Zhenfang Wang <zhenfang.wang@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Link: https://lore.kernel.org/r/170dbbc6d5366b6fa974ce2d366652e23a334251.1570609788.git.baolin.wang@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-12 19:20:54 +01:00
Radhey Shyam Pandey
6040f96d51 dmaengine: xilinx_dma: Fix control reg update in vdma_channel_set_config
[ Upstream commit 6c6de1ddb1 ]

In vdma_channel_set_config clear the delay, frame count and master mask
before updating their new values. It avoids programming incorrect state
when input parameters are different from default.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Acked-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1569495060-18117-3-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-12 19:20:53 +01:00
Tony Lindgren
3e285a5c14 dmaengine: cppi41: Fix cppi41_dma_prep_slave_sg() when idle
commit bacdcb6675 upstream.

Yegor Yefremov <yegorslists@googlemail.com> reported that musb and ftdi
uart can fail for the first open of the uart unless connected using
a hub.

This is because the first dma call done by musb_ep_program() must wait
if cppi41 is PM runtime suspended. Otherwise musb_ep_program() continues
with other non-dma packets before the DMA transfer is started causing at
least ftdi uarts to fail to receive data.

Let's fix the issue by waking up cppi41 with PM runtime calls added to
cppi41_dma_prep_slave_sg() and return NULL if still idled. This way we
have musb_ep_program() continue with PIO until cppi41 is awake.

Fixes: fdea2d09b9 ("dmaengine: cppi41: Add basic PM runtime support")
Reported-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Cc: stable@vger.kernel.org # v4.9+
Link: https://lore.kernel.org/r/20191023153138.23442-1-tony@atomide.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-06 13:06:21 +01:00
Jeffrey Hugo
a0e406be17 dmaengine: qcom: bam_dma: Fix resource leak
commit 7667819385 upstream.

bam_dma_terminate_all() will leak resources if any of the transactions are
committed to the hardware (present in the desc fifo), and not complete.
Since bam_dma_terminate_all() does not cause the hardware to be updated,
the hardware will still operate on any previously committed transactions.
This can cause memory corruption if the memory for the transaction has been
reassigned, and will cause a sync issue between the BAM and its client(s).

Fix this by properly updating the hardware in bam_dma_terminate_all().

Fixes: e7c0fe2a5c ("dmaengine: add Qualcomm BAM dma driver")
Signed-off-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191017152606.34120-1-jeffrey.l.hugo@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-06 13:06:21 +01:00
Peter Ujfalusi
213077da3e dmaengine: ti: edma: Do not reset reserved paRAM slots
[ Upstream commit c5dbe60664 ]

Skip resetting paRAM slots marked as reserved as they might be used by
other cores.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20190823125618.8133-2-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05 13:09:54 +02:00
Arnd Bergmann
482c1d0a7c dmaengine: iop-adma: use correct printk format strings
[ Upstream commit 00c9755524 ]

When compile-testing on other architectures, we get lots of warnings
about incorrect format strings, like:

   drivers/dma/iop-adma.c: In function 'iop_adma_alloc_slots':
   drivers/dma/iop-adma.c:307:6: warning: format '%x' expects argument of type 'unsigned int', but argument 6 has type 'dma_addr_t {aka long long unsigned int}' [-Wformat=]

   drivers/dma/iop-adma.c: In function 'iop_adma_prep_dma_memcpy':
>> drivers/dma/iop-adma.c:518:40: warning: format '%u' expects argument of type 'unsigned int', but argument 5 has type 'size_t {aka long unsigned int}' [-Wformat=]

Use %zu for printing size_t as required, and cast the dma_addr_t
arguments to 'u64' for printing with %llx. Ideally this should use
the %pad format string, but that requires an lvalue argument that
doesn't work here.

Link: https://lore.kernel.org/r/20190809163334.489360-3-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05 13:09:42 +02:00
Stefan Wahren
fdcf06a35b dmaengine: bcm2835: Print error in case setting DMA mask fails
[ Upstream commit 72503b25ee ]

During enabling of the RPi 4, we found out that the driver doesn't provide
a helpful error message in case setting DMA mask fails. So add one.

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Link: https://lore.kernel.org/r/1563297318-4900-1-git-send-email-wahrenst@gmx.net
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05 13:09:34 +02:00
Wenwen Wang
72c762b01e dmaengine: ti: omap-dma: Add cleanup in omap_dma_probe()
[ Upstream commit 962411b05a ]

If devm_request_irq() fails to disable all interrupts, no cleanup is
performed before retuning the error. To fix this issue, invoke
omap_dma_free() to do the cleanup.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/1565938570-7528-1-git-send-email-wenwen@cs.uga.edu
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-21 07:17:11 +02:00
Wenwen Wang
d04b522a65 dmaengine: ti: dma-crossbar: Fix a memory leak bug
[ Upstream commit 2c231c0c1d ]

In ti_dra7_xbar_probe(), 'rsv_events' is allocated through kcalloc(). Then
of_property_read_u32_array() is invoked to search for the property.
However, if this process fails, 'rsv_events' is not deallocated, leading to
a memory leak bug. To fix this issue, free 'rsv_events' before returning
the error.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/1565938136-7249-1-git-send-email-wenwen@cs.uga.edu
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-21 07:17:11 +02:00
Hans Verkuil
7f4b81365e omap-dma/omap_vout_vrfb: fix off-by-one fi value
[ Upstream commit d555c34338 ]

The OMAP 4 TRM specifies that when using double-index addressing
the address increases by the ES plus the EI value minus 1 within
a frame. When a full frame is transferred, the address increases
by the ES plus the frame index (FI) value minus 1.

The omap-dma code didn't account for the 'minus 1' in the FI register.
To get correct addressing, add 1 to the src_icg value.

This was found when testing a hacked version of the media m2m-deinterlace.c
driver on a Pandaboard.

The only other source that uses this feature is omap_vout_vrfb.c,
and that adds a + 1 when setting the dst_icg. This is a workaround
for the broken omap-dma.c behavior. So remove the workaround at the
same time that we fix omap-dma.c.

I tested the omap_vout driver with a Beagle XM board to check that
the '+ 1' in omap_vout_vrfb.c was indeed a workaround for the omap-dma
bug.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Link: https://lore.kernel.org/r/952e7f51-f208-9333-6f58-b7ed20d2ea0b@xs4all.nl
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-06 10:21:56 +02:00
Jia-Ju Bai
71d24f45f9 dmaengine: stm32-mdma: Fix a possible null-pointer dereference in stm32_mdma_irq_handler()
[ Upstream commit 39c71a5b82 ]

In stm32_mdma_irq_handler(), chan is checked on line 1368.
When chan is NULL, it is still used on line 1369:
    dev_err(chan2dev(chan), "MDMA channel not initialized\n");

Thus, a possible null-pointer dereference may occur.

To fix this bug, "dev_dbg(mdma2dev(dmadev), ...)" is used instead.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Fixes: a4ffb13c89 ("dmaengine: Add STM32 MDMA driver")
Link: https://lore.kernel.org/r/20190729020849.17971-1-baijiaju1990@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-06 10:21:56 +02:00
Arnd Bergmann
2013d6ec0b dmaengine: ste_dma40: fix unneeded variable warning
[ Upstream commit 5d6fb56072 ]

clang-9 points out that there are two variables that depending on the
configuration may only be used in an ARRAY_SIZE() expression but not
referenced:

drivers/dma/ste_dma40.c:145:12: error: variable 'd40_backup_regs' is not needed and will not be emitted [-Werror,-Wunneeded-internal-declaration]
static u32 d40_backup_regs[] = {
           ^
drivers/dma/ste_dma40.c:214:12: error: variable 'd40_backup_regs_chan' is not needed and will not be emitted [-Werror,-Wunneeded-internal-declaration]
static u32 d40_backup_regs_chan[] = {

Mark these __maybe_unused to shut up the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20190712091357.744515-1-arnd@arndb.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-06 10:21:54 +02:00
Geert Uytterhoeven
cf0fcc7fe2 dmaengine: rcar-dmac: Reject zero-length slave DMA requests
[ Upstream commit 78efb76ab4 ]

While the .device_prep_slave_sg() callback rejects empty scatterlists,
it still accepts single-entry scatterlists with a zero-length segment.
These may happen if a driver calls dmaengine_prep_slave_single() with a
zero len parameter.  The corresponding DMA request will never complete,
leading to messages like:

    rcar-dmac e7300000.dma-controller: Channel Address Error happen

and DMA timeouts.

Although requesting a zero-length DMA request is a driver bug, rejecting
it early eases debugging.  Note that the .device_prep_dma_memcpy()
callback already rejects requests to copy zero bytes.

Reported-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Analyzed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-06 19:06:48 +02:00
Dmitry Osipenko
d8388cbd43 dmaengine: tegra-apb: Error out if DMA_PREP_INTERRUPT flag is unset
[ Upstream commit dc161064be ]

Apparently driver was never tested with DMA_PREP_INTERRUPT flag being
unset since it completely disables interrupt handling instead of skipping
the callbacks invocations, hence putting channel into unusable state.

The flag is always set by all of kernel drivers that use APB DMA, so let's
error out in otherwise case for consistency. It won't be difficult to
support that case properly if ever will be needed.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-06 19:06:47 +02:00
Sven Van Asbroeck
09593c25b9 dmaengine: imx-sdma: fix use-after-free on probe error path
[ Upstream commit 2b8066c3de ]

If probe() fails anywhere beyond the point where
sdma_get_firmware() is called, then a kernel oops may occur.

Problematic sequence of events:
1. probe() calls sdma_get_firmware(), which schedules the
   firmware callback to run when firmware becomes available,
   using the sdma instance structure as the context
2. probe() encounters an error, which deallocates the
   sdma instance structure
3. firmware becomes available, firmware callback is
   called with deallocated sdma instance structure
4. use after free - kernel oops !

Solution: only attempt to load firmware when we're certain
that probe() will succeed. This guarantees that the firmware
callback's context will remain valid.

Note that the remove() path is unaffected by this issue: the
firmware loader will increment the driver module's use count,
ensuring that the module cannot be unloaded while the
firmware callback is pending or running.

Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
Reviewed-by: Robin Gong <yibin.gong@nxp.com>
[vkoul: fixed braces for if condition]
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-26 09:13:56 +02:00
Robin Gong
f37de75cb8 dmaengine: imx-sdma: remove BD_INTR for channel0
commit 3f93a4f297 upstream.

It is possible for an irq triggered by channel0 to be received later
after clks are disabled once firmware loaded during sdma probe. If
that happens then clearing them by writing to SDMA_H_INTR won't work
and the kernel will hang processing infinite interrupts. Actually,
don't need interrupt triggered on channel0 since it's pollling
SDMA_H_STATSTOP to know channel0 done rather than interrupt in
current code, just clear BD_INTR to disable channel0 interrupt to
avoid the above case.
This issue was brought by commit 1d069bfa3c ("dmaengine: imx-sdma:
ack channel 0 IRQ in the interrupt handler") which didn't take care
the above case.

Fixes: 1d069bfa3c ("dmaengine: imx-sdma: ack channel 0 IRQ in the interrupt handler")
Cc: stable@vger.kernel.org #5.0+
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Reported-by: Sven Van Asbroeck <thesven73@gmail.com>
Tested-by: Sven Van Asbroeck <thesven73@gmail.com>
Reviewed-by: Michael Olbrich <m.olbrich@pengutronix.de>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-10 09:53:48 +02:00
Sricharan R
018c968de7 dmaengine: qcom: bam_dma: Fix completed descriptors count
commit f603422544 upstream.

One space is left unused in circular FIFO to differentiate
'full' and 'empty' cases. So take that in to account while
counting for the descriptors completed.

Fixes the issue reported here,
	https://lkml.org/lkml/2019/6/18/669

Cc: stable@vger.kernel.org
Reported-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-10 09:53:48 +02:00
Eric Long
8f3793bfa3 dmaengine: sprd: Fix block length overflow
[ Upstream commit 89d03b3c12 ]

The maximum value of block length is 0xffff, so if the configured transfer length
is more than 0xffff, that will cause block length overflow to lead a configuration
error.

Thus we can set block length as the maximum burst length to avoid this issue, since
the maximum burst length will not be a big value which is more than 0xffff.

Signed-off-by: Eric Long <eric.long@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-25 11:35:55 +08:00
Colin Ian King
e478abd4eb dmaengine: dw-axi-dmac: fix null dereference when pointer first is null
[ Upstream commit 0788611c9a ]

In the unlikely event that axi_desc_get returns a null desc in the
very first iteration of the while-loop the error exit path ends
up calling axi_desc_put on a null pointer 'first' and this causes
a null pointer dereference.  Fix this by adding a null check on
pointer 'first' before calling axi_desc_put.

Addresses-Coverity: ("Explicit null dereference")
Fixes: 1fe20f1b84 ("dmaengine: Introduce DW AXI DMAC driver")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-25 11:35:55 +08:00
Andy Shevchenko
9fdcb04e80 dmaengine: idma64: Use actual device for DMA transfers
[ Upstream commit 5ba846b1ee ]

Intel IOMMU, when enabled, tries to find the domain of the device,
assuming it's a PCI one, during DMA operations, such as mapping or
unmapping. Since we are splitting the actual PCI device to couple of
children via MFD framework (see drivers/mfd/intel-lpss.c for details),
the DMA device appears to be a platform one, and thus not an actual one
that performs DMA. In a such situation IOMMU can't find or allocate
a proper domain for its operations. As a result, all DMA operations are
failed.

In order to fix this, supply parent of the platform device
to the DMA engine framework and fix filter functions accordingly.

We may rely on the fact that parent is a real PCI device, because no
other configuration is present in the wild.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [for tty parts]
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-15 11:54:10 +02:00
Sameer Pujar
6b2d1934d1 dmaengine: tegra210-adma: use devm_clk_*() helpers
[ Upstream commit f6ed6491d5 ]

adma driver is using pm_clk_*() interface for managing clock resources.
With this it is observed that clocks remain ON always. This happens on
Tegra devices which use BPMP co-processor to manage clock resources,
where clocks are enabled during prepare phase. This is necessary because
clocks to BPMP are always blocking. When pm_clk_*() interface is used on
such Tegra devices, clock prepare count is not balanced till remove call
happens for the driver and hence clocks are seen ON always. Thus this
patch replaces pm_clk_*() with devm_clk_*() framework.

Suggested-by: Mohan Kumar D <mkumard@nvidia.com>
Reviewed-by: Jonathan Hunter <jonathanh@nvidia.com>
Signed-off-by: Sameer Pujar <spujar@nvidia.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:46:31 -07:00
Nicolas Ferre
83544b04a4 dmaengine: at_xdmac: remove BUG_ON macro in tasklet
[ Upstream commit e2c114c06d ]

Even if this case shouldn't happen when controller is properly programmed,
it's still better to avoid dumping a kernel Oops for this.
As the sequence may happen only for debugging purposes, log the error and
just finish the tasklet call.

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:46:17 -07:00
Sugar Zhang
1d057fefa0 dmaengine: pl330: _stop: clear interrupt status
[ Upstream commit 2da254cc79 ]

This patch kill instructs the DMAC to immediately terminate
execution of a thread. and then clear the interrupt status,
at last, stop generating interrupts for DMA_SEV. to guarantee
the next dma start is clean. otherwise, one interrupt maybe leave
to next start and make some mistake.

we can reporduce the problem as follows:

DMASEV: modify the event-interrupt resource, and if the INTEN sets
function as interrupt, the DMAC will set irq<event_num> HIGH to
generate interrupt. write INTCLR to clear interrupt.

	DMA EXECUTING INSTRUCTS		DMA TERMINATE
		|				|
		|				|
	       ...			      _stop
		|				|
		|			spin_lock_irqsave
	     DMASEV				|
		|				|
		|			    mask INTEN
		|				|
		|			     DMAKILL
		|				|
		|			spin_unlock_irqrestore

in above case, a interrupt was left, and if we unmask INTEN, the DMAC
will set irq<event_num> HIGH to generate interrupt.

to fix this, do as follows:

	DMA EXECUTING INSTRUCTS		DMA TERMINATE
		|				|
		|				|
	       ...			      _stop
		|				|
		|			spin_lock_irqsave
	     DMASEV				|
		|				|
		|			     DMAKILL
		|				|
		|			   clear INTCLR
		|			    mask INTEN
		|				|
		|			spin_unlock_irqrestore

Signed-off-by: Sugar Zhang <sugar.zhang@rock-chips.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:46:14 -07:00
Sameer Pujar
19c2dd5025 dmaengine: tegra210-dma: free dma controller in remove()
[ Upstream commit f030e41950 ]

Following kernel panic is seen during DMA driver unload->load sequence
==========================================================================
Unable to handle kernel paging request at virtual address ffffff8001198880
Internal error: Oops: 86000007 [#1] PREEMPT SMP
CPU: 0 PID: 5907 Comm: HwBinder:4123_1 Tainted: G C 4.9.128-tegra-g065839f
Hardware name: galen (DT)
task: ffffffc3590d1a80 task.stack: ffffffc3d0678000
PC is at 0xffffff8001198880
LR is at of_dma_request_slave_channel+0xd8/0x1f8
pc : [<ffffff8001198880>] lr : [<ffffff8008746f30>] pstate: 60400045
sp : ffffffc3d067b710
x29: ffffffc3d067b710 x28: 000000000000002f
x27: ffffff800949e000 x26: ffffff800949e750
x25: ffffff800949e000 x24: ffffffbefe817d84
x23: ffffff8009f77cb0 x22: 0000000000000028
x21: ffffffc3ffda49c8 x20: 0000000000000029
x19: 0000000000000001 x18: ffffffffffffffff
x17: 0000000000000000 x16: ffffff80082b66a0
x15: ffffff8009e78250 x14: 000000000000000a
x13: 0000000000000038 x12: 0101010101010101
x11: 0000000000000030 x10: 0101010101010101
x9 : fffffffffffffffc x8 : 7f7f7f7f7f7f7f7f
x7 : 62ff726b6b64622c x6 : 0000000000008064
x5 : 6400000000000000 x4 : ffffffbefe817c44
x3 : ffffffc3ffda3e08 x2 : ffffff8001198880
x1 : ffffffc3d48323c0 x0 : ffffffc3d067b788

Process HwBinder:4123_1 (pid: 5907, stack limit = 0xffffffc3d0678028)
Call trace:
[<ffffff8001198880>] 0xffffff8001198880
[<ffffff80087459f8>] dma_request_chan+0x50/0x1f0
[<ffffff8008745bc0>] dma_request_slave_channel+0x28/0x40
[<ffffff8001552c44>] tegra_alt_pcm_open+0x114/0x170
[<ffffff8008d65fa4>] soc_pcm_open+0x10c/0x878
[<ffffff8008d18618>] snd_pcm_open_substream+0xc0/0x170
[<ffffff8008d1878c>] snd_pcm_open+0xc4/0x240
[<ffffff8008d189e0>] snd_pcm_playback_open+0x58/0x80
[<ffffff8008cfc6d4>] snd_open+0xb4/0x178
[<ffffff8008250628>] chrdev_open+0xb8/0x1d0
[<ffffff8008246fdc>] do_dentry_open+0x214/0x318
[<ffffff80082485d0>] vfs_open+0x58/0x88
[<ffffff800825bce0>] do_last+0x450/0xde0
[<ffffff800825c718>] path_openat+0xa8/0x368
[<ffffff800825dd84>] do_filp_open+0x8c/0x110
[<ffffff8008248a74>] do_sys_open+0x164/0x220
[<ffffff80082b66dc>] compat_SyS_openat+0x3c/0x50
[<ffffff8008083040>] el0_svc_naked+0x34/0x38
---[ end trace 67e6d544e65b5145 ]---
Kernel panic - not syncing: Fatal exception
==========================================================================

In device probe(), of_dma_controller_register() registers DMA controller.
But when driver is removed, this is not freed. During driver reload this
results in data abort and kernel panic. Add of_dma_controller_free() in
driver remove path to fix the issue.

Fixes: f46b195799 ("dmaengine: tegra-adma: Add support for Tegra210 ADMA")
Signed-off-by: Sameer Pujar <spujar@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:46:08 -07:00
Achim Dahlhoff
129c337c66 dmaengine: sh: rcar-dmac: Fix glitch in dmaengine_tx_status
commit 6e7da74775 upstream.

The tx_status poll in the rcar_dmac driver reads the status register
which indicates which chunk is busy (DMACHCRB). Afterwards the point
inside the chunk is read from DMATCRB. It is possible that the chunk
has changed between the two reads. The result is a non-monotonous
increase of the residue. Fix this by introducing a 'safe read' logic.

Fixes: 73a47bd0da ("dmaengine: rcar-dmac: use TCRB instead of TCR for residue")
Signed-off-by: Achim Dahlhoff <Achim.Dahlhoff@de.bosch.com>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: <stable@vger.kernel.org> # v4.16+
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-02 09:58:55 +02:00
Dirk Behme
0f00e1c599 dmaengine: sh: rcar-dmac: With cyclic DMA residue 0 is valid
commit 907bd68a2e upstream.

Having a cyclic DMA, a residue 0 is not an indication of a completed
DMA. In case of cyclic DMA make sure that dma_set_residue() is called
and with this a residue of 0 is forwarded correctly to the caller.

Fixes: 3544d28788 ("dmaengine: rcar-dmac: use result of updated get_residue in tx_status")
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Achim Dahlhoff <Achim.Dahlhoff@de.bosch.com>
Signed-off-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@renesas.com>
Signed-off-by: Yao Lihua <ylhuajnu@outlook.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: <stable@vger.kernel.org> # v4.8+
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-02 09:58:55 +02:00
Ben Dooks
6d2817e2ab dmaengine: tegra: avoid overflow of byte tracking
[ Upstream commit e486df3930 ]

The dma_desc->bytes_transferred counter tracks the number of bytes
moved by the DMA channel. This is then used to calculate the information
passed back in the in the tegra_dma_tx_status callback, which is usually
fine.

When the DMA channel is configured as continous, then the bytes_transferred
counter will increase over time and eventually overflow to become negative
so the residue count will become invalid and the ALSA sound-dma code will
report invalid hardware pointer values to the application. This results in
some users becoming confused about the playout position and putting audio
data in the wrong place.

To fix this issue, always ensure the bytes_transferred field is modulo the
size of the request. We only do this for the case of the cyclic transfer
done ISR as anyone attempting to move 2GiB of DMA data in one transfer
is unlikely.

Note, we don't fix the issue that we should /never/ transfer a negative
number of bytes so we could make those fields unsigned.

Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:33:16 +02:00
Shunyong Yang
24296fbc54 dmaengine: qcom_hidma: initialize tx flags in hidma_prep_dma_*
[ Upstream commit 875aac8a46 ]

In async_tx_test_ack(), it uses flags in struct dma_async_tx_descriptor
to check the ACK status. As hidma reuses the descriptor in a free list
when hidma_prep_dma_*(memcpy/memset) is called, the flag will keep ACKed
if the descriptor has been used before. This will cause a BUG_ON in
async_tx_quiesce().

  kernel BUG at crypto/async_tx/async_tx.c:282!
  Internal error: Oops - BUG: 0 1 SMP
  ...
  task: ffff8017dd3ec000 task.stack: ffff8017dd3e8000
  PC is at async_tx_quiesce+0x54/0x78 [async_tx]
  LR is at async_trigger_callback+0x98/0x110 [async_tx]

This patch initializes flags in dma_async_tx_descriptor by the flags
passed from the caller when hidma_prep_dma_*(memcpy/memset) is called.

Cc: Joey Zheng <yu.zheng@hxt-semitech.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Signed-off-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:33:15 +02:00
Shunyong Yang
c55f4a6e79 dmaengine: qcom_hidma: assign channel cookie correctly
[ Upstream commit 546c054755 ]

When dma_cookie_complete() is called in hidma_process_completed(),
dma_cookie_status() will return DMA_COMPLETE in hidma_tx_status(). Then,
hidma_txn_is_success() will be called to use channel cookie
mchan->last_success to do additional DMA status check. Current code
assigns mchan->last_success after dma_cookie_complete(). This causes
a race condition of dma_cookie_status() returns DMA_COMPLETE before
mchan->last_success is assigned correctly. The race will cause
hidma_tx_status() return DMA_ERROR but the transaction is actually a
success. Moreover, in async_tx case, it will cause a timeout panic
in async_tx_quiesce().

 Kernel panic - not syncing: async_tx_quiesce: DMA error waiting for
 transaction
 ...
 Call trace:
 [<ffff000008089994>] dump_backtrace+0x0/0x1f4
 [<ffff000008089bac>] show_stack+0x24/0x2c
 [<ffff00000891e198>] dump_stack+0x84/0xa8
 [<ffff0000080da544>] panic+0x12c/0x29c
 [<ffff0000045d0334>] async_tx_quiesce+0xa4/0xc8 [async_tx]
 [<ffff0000045d03c8>] async_trigger_callback+0x70/0x1c0 [async_tx]
 [<ffff0000048b7d74>] raid_run_ops+0x86c/0x1540 [raid456]
 [<ffff0000048bd084>] handle_stripe+0x5e8/0x1c7c [raid456]
 [<ffff0000048be9ec>] handle_active_stripes.isra.45+0x2d4/0x550 [raid456]
 [<ffff0000048beff4>] raid5d+0x38c/0x5d0 [raid456]
 [<ffff000008736538>] md_thread+0x108/0x168
 [<ffff0000080fb1cc>] kthread+0x10c/0x138
 [<ffff000008084d34>] ret_from_fork+0x10/0x18

Cc: Joey Zheng <yu.zheng@hxt-semitech.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Signed-off-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:33:15 +02:00
Anders Roxell
afacaf8554 dmaengine: imx-dma: fix warning comparison of distinct pointer types
[ Upstream commit 9227ab5643 ]

The warning got introduced by commit 930507c183 ("arm64: add basic
Kconfig symbols for i.MX8"). Since it got enabled for arm64. The warning
haven't been seen before since size_t was 'unsigned int' when built on
arm32.

../drivers/dma/imx-dma.c: In function ‘imxdma_sg_next’:
../include/linux/kernel.h:846:29: warning: comparison of distinct pointer types lacks a cast
   (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
                             ^~
../include/linux/kernel.h:860:4: note: in expansion of macro ‘__typecheck’
   (__typecheck(x, y) && __no_side_effects(x, y))
    ^~~~~~~~~~~
../include/linux/kernel.h:870:24: note: in expansion of macro ‘__safe_cmp’
  __builtin_choose_expr(__safe_cmp(x, y), \
                        ^~~~~~~~~~
../include/linux/kernel.h:879:19: note: in expansion of macro ‘__careful_cmp’
 #define min(x, y) __careful_cmp(x, y, <)
                   ^~~~~~~~~~~~~
../drivers/dma/imx-dma.c:288:8: note: in expansion of macro ‘min’
  now = min(d->len, sg_dma_len(sg));
        ^~~

Rework so that we use min_t and pass in the size_t that returns the
minimum of two values, using the specified type.

Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:33:15 +02:00
Phuong Nguyen
c7fd1a968c dmaengine: usb-dmac: Make DMAC system sleep callbacks explicit
commit d9140a0da4 upstream.

This commit fixes the issue that USB-DMAC hangs silently after system
resumes on R-Car Gen3 hence renesas_usbhs will not work correctly
when using USB-DMAC for bulk transfer e.g. ethernet or serial
gadgets.

The issue can be reproduced by these steps:
 1. modprobe g_serial
 2. Suspend and resume system.
 3. connect a usb cable to host side
 4. Transfer data from Host to Target
 5. cat /dev/ttyGS0 (Target side)
 6. echo "test" > /dev/ttyACM0 (Host side)

The 'cat' will not result anything. However, system still can work
normally.

Currently, USB-DMAC driver does not have system sleep callbacks hence
this driver relies on the PM core to force runtime suspend/resume to
suspend and reinitialize USB-DMAC during system resume. After
the commit 17218e0092 ("PM / genpd: Stop/start devices without
pm_runtime_force_suspend/resume()"), PM core will not force
runtime suspend/resume anymore so this issue happens.

To solve this, make system suspend resume explicit by using
pm_runtime_force_{suspend,resume}() as the system sleep callbacks.
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS() is used to make sure USB-DMAC
suspended after and initialized before renesas_usbhs."

Signed-off-by: Phuong Nguyen <phuong.nguyen.xw@renesas.com>
Signed-off-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@renesas.com>
Cc: <stable@vger.kernel.org> # v4.16+
[shimoda: revise the commit log and add Cc tag]
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 20:10:04 +01:00
Andy Shevchenko
0203f0c963 dmaengine: dmatest: Abort test in case of mapping error
[ Upstream commit 6454368a80 ]

In case of mapping error the DMA addresses are invalid and continuing
will screw system memory or potentially something else.

[  222.480310] dmatest: dma0chan7-copy0: summary 1 tests, 3 failures 6 iops 349 KB/s (0)
...
[  240.912725] check: Corrupted low memory at 00000000c7c75ac9 (2940 phys) = 5656000000000000
[  240.921998] check: Corrupted low memory at 000000005715a1cd (2948 phys) = 279f2aca5595ab2b
[  240.931280] check: Corrupted low memory at 000000002f4024c0 (2950 phys) = 5e5624f349e793cf
...

Abort any test if mapping failed.

Fixes: 4076e755db ("dmatest: convert to dmaengine_unmap_data")
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:02:36 -07:00
Codrin Ciubotariu
f3ffd4559d dmaengine: at_xdmac: Fix wrongfull report of a channel as in use
[ Upstream commit dc3f595b66 ]

atchan->status variable is used to store two different information:
 - pass channel interrupts status from interrupt handler to tasklet;
 - channel information like whether it is cyclic or paused;

This causes a bug when device_terminate_all() is called,
(AT_XDMAC_CHAN_IS_CYCLIC cleared on atchan->status) and then a late End
of Block interrupt arrives (AT_XDMAC_CIS_BIS), which sets bit 0 of
atchan->status. Bit 0 is also used for AT_XDMAC_CHAN_IS_CYCLIC, so when
a new descriptor for a cyclic transfer is created, the driver reports
the channel as in use:

if (test_and_set_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status)) {
	dev_err(chan2dev(chan), "channel currently used\n");
	return NULL;
}

This patch fixes the bug by adding a different struct member to keep
the interrupts status separated from the channel status bits.

Fixes: e1f7c9eee7 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver")
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:02:36 -07:00
Leonid Iziumtsev
4a9e4bcda7 dmaengine: imx-dma: fix wrong callback invoke
commit 341198eda7 upstream.

Once the "ld_queue" list is not empty, next descriptor will migrate
into "ld_active" list. The "desc" variable will be overwritten
during that transition. And later the dmaengine_desc_get_callback_invoke()
will use it as an argument. As result we invoke wrong callback.

That behaviour was in place since:
commit fcaaba6c71 ("dmaengine: imx-dma: fix callback path in tasklet").
But after commit 4cd13c21b2 ("softirq: Let ksoftirqd do its job")
things got worse, since possible delay between tasklet_schedule()
from DMA irq handler and actual tasklet function execution got bigger.
And that gave more time for new DMA request to be submitted and
to be put into "ld_queue" list.

It has been noticed that DMA issue is causing problems for "mxc-mmc"
driver. While stressing the system with heavy network traffic and
writing/reading to/from sd card simultaneously the timeout may happen:

10013000.sdhci: mxcmci_watchdog: read time out (status = 0x30004900)

That often lead to file system corruption.

Signed-off-by: Leonid Iziumtsev <leonid.iziumtsev@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12 19:47:24 +01:00
Lukas Wunner
84c1d56275 dmaengine: bcm2835: Fix abort of transactions
commit 9e528c799d upstream.

There are multiple issues with bcm2835_dma_abort() (which is called on
termination of a transaction):

* The algorithm to abort the transaction first pauses the channel by
  clearing the ACTIVE flag in the CS register, then waits for the PAUSED
  flag to clear.  Page 49 of the spec documents the latter as follows:

  "Indicates if the DMA is currently paused and not transferring data.
   This will occur if the active bit has been cleared [...]"
   https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf

  So the function is entering an infinite loop because it is waiting for
  PAUSED to clear which is always set due to the function having cleared
  the ACTIVE flag.  The only thing that's saving it from itself is the
  upper bound of 10000 loop iterations.

  The code comment says that the intention is to "wait for any current
  AXI transfer to complete", so the author probably wanted to check the
  WAITING_FOR_OUTSTANDING_WRITES flag instead.  Amend the function
  accordingly.

* The CS register is only read at the beginning of the function.  It
  needs to be read again after pausing the channel and before checking
  for outstanding writes, otherwise writes which were issued between
  the register read at the beginning of the function and pausing the
  channel may not be waited for.

* The function seeks to abort the transfer by writing 0 to the NEXTCONBK
  register and setting the ABORT and ACTIVE flags.  Thereby, the 0 in
  NEXTCONBK is sought to be loaded into the CONBLK_AD register.  However
  experimentation has shown this approach to not work:  The CONBLK_AD
  register remains the same as before and the CS register contains
  0x00000030 (PAUSED | DREQ_STOPS_DMA).  In other words, the control
  block is not aborted but merely paused and it will be resumed once the
  next DMA transaction is started.  That is absolutely not the desired
  behavior.

  A simpler approach is to set the channel's RESET flag instead.  This
  reliably zeroes the NEXTCONBK as well as the CS register.  It requires
  less code and only a single MMIO write.  This is also what popular
  user space DMA drivers do, e.g.:
  https://github.com/metachris/RPIO/blob/master/source/c_pwm/pwm.c

  Note that the spec is contradictory whether the NEXTCONBK register
  is writeable at all.  On the one hand, page 41 claims:

  "The value loaded into the NEXTCONBK register can be overwritten so
  that the linked list of Control Block data structures can be
  dynamically altered. However it is only safe to do this when the DMA
  is paused."

  On the other hand, page 40 specifies:

  "Only three registers in each channel's register set are directly
  writeable (CS, CONBLK_AD and DEBUG). The other registers (TI,
  SOURCE_AD, DEST_AD, TXFR_LEN, STRIDE & NEXTCONBK), are automatically
  loaded from a Control Block data structure held in external memory."

Fixes: 96286b5766 ("dmaengine: Add support for BCM2835")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v3.14+
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Florian Meier <florian.meier@koalo.de>
Cc: Clive Messer <clive.m.messer@gmail.com>
Cc: Matthias Reichl <hias@horus.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Florian Kauer <florian.kauer@koalo.de>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12 19:47:24 +01:00
Lukas Wunner
916eb6bd8d dmaengine: bcm2835: Fix interrupt race on RT
commit f7da7782ab upstream.

If IRQ handlers are threaded (either because CONFIG_PREEMPT_RT_BASE is
enabled or "threadirqs" was passed on the command line) and if system
load is sufficiently high that wakeup latency of IRQ threads degrades,
SPI DMA transactions on the BCM2835 occasionally break like this:

ks8851 spi0.0: SPI transfer timed out
bcm2835-dma 3f007000.dma: DMA transfer could not be terminated
ks8851 spi0.0 eth2: ks8851_rdfifo: spi_sync() failed

The root cause is an assumption made by the DMA driver which is
documented in a code comment in bcm2835_dma_terminate_all():

/*
 * Stop DMA activity: we assume the callback will not be called
 * after bcm_dma_abort() returns (even if it does, it will see
 * c->desc is NULL and exit.)
 */

That assumption falls apart if the IRQ handler bcm2835_dma_callback() is
threaded: A client may terminate a descriptor and issue a new one
before the IRQ handler had a chance to run. In fact the IRQ handler may
miss an *arbitrary* number of descriptors. The result is the following
race condition:

1. A descriptor finishes, its interrupt is deferred to the IRQ thread.
2. A client calls dma_terminate_async() which sets channel->desc = NULL.
3. The client issues a new descriptor. Because channel->desc is NULL,
   bcm2835_dma_issue_pending() immediately starts the descriptor.
4. Finally the IRQ thread runs and writes BCM2835_DMA_INT to the CS
   register to acknowledge the interrupt. This clears the ACTIVE flag,
   so the newly issued descriptor is paused in the middle of the
   transaction. Because channel->desc is not NULL, the IRQ thread
   finalizes the descriptor and tries to start the next one.

I see two possible solutions: The first is to call synchronize_irq()
in bcm2835_dma_issue_pending() to wait until the IRQ thread has
finished before issuing a new descriptor. The downside of this approach
is unnecessary latency if clients desire rapidly terminating and
re-issuing descriptors and don't have any use for an IRQ callback.
(The SPI TX DMA channel is a case in point.)

A better alternative is to make the IRQ thread recognize that it has
missed descriptors and avoid finalizing the newly issued descriptor.
So first of all, set the ACTIVE flag when acknowledging the interrupt.
This keeps a newly issued descriptor running.

If the descriptor was finished, the channel remains idle despite the
ACTIVE flag being set. However the ACTIVE flag can then no longer be
used to check whether the channel is idle, so instead check whether
the register containing the current control block address is zero
and finalize the current descriptor only if so.

That way, there is no impact on latency and throughput if the client
doesn't care for the interrupt: Only minimal additional overhead is
introduced for non-cyclic descriptors as one further MMIO read is
necessary per interrupt to check for idleness of the channel. Cyclic
descriptors are sped up slightly by removing one MMIO write per
interrupt.

Fixes: 96286b5766 ("dmaengine: Add support for BCM2835")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v3.14+
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Florian Meier <florian.meier@koalo.de>
Cc: Clive Messer <clive.m.messer@gmail.com>
Cc: Matthias Reichl <hias@horus.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Florian Kauer <florian.kauer@koalo.de>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12 19:47:24 +01:00
Nathan Chancellor
cefe8d2c08 dmaengine: xilinx_dma: Remove __aligned attribute on zynqmp_dma_desc_ll
[ Upstream commit aeaebcc17c ]

Clang warns:

drivers/dma/xilinx/zynqmp_dma.c:166:4: warning: attribute 'aligned' is
ignored, place it after "struct" to apply attribute to type declaration
[-Wignored-attributes]
}; __aligned(64)
   ^
./include/linux/compiler_types.h:200:38: note: expanded from macro
'__aligned'
                                               ^
1 warning generated.

As Nick pointed out in the previous version of this patch, the author
likely intended for this struct to be 8-byte (64-bit) aligned, not
64-byte, which is the default. Remove the hanging __aligned attribute.

Fixes: b0cc417c16 ("dmaengine: Add Xilinx zynqmp dma engine driver support")
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:02 +01:00