Commit graph

23 commits

Author SHA1 Message Date
Shravan Chippa
58eea79a1c dmaengine: sf-pdma: add mpfs-pdma compatible name
Sifive platform dma (sf-pdma) has both in-order and out-of-order
configurations but sf-pdam driver configured to do in-order DMA
transfers, with out-of-order configuration got better throughput
in the PolarFire SoC platform.

Add a PolarFire SoC specific compatible and code to support
for out-of-order dma transfers

Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Shravan Chippa <shravan.chippa@microchip.com>
Link: https://lore.kernel.org/r/20231208103856.3732998-4-shravan.chippa@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2023-12-11 16:33:22 +05:30
Shravan Chippa
8e578b47e6 dmaengine: sf-pdma: Support of_dma_controller_register()
Update sf-pdma driver to adopt generic DMA device tree bindings.
It calls of_dma_controller_register() with of_dma_xlate_by_chan_id
to get the generic DMA device tree helper support and the DMA
clients can look up the sf-pdma controller using standard APIs.

Signed-off-by: Shravan Chippa <shravan.chippa@microchip.com>
Link: https://lore.kernel.org/r/20231208103856.3732998-2-shravan.chippa@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2023-12-11 16:33:22 +05:30
Kees Cook
1539a22e14 dmaengine: sf-pdma: Annotate struct sf_pdma with __counted_by
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct sf_pdma.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Vinod Koul <vkoul@kernel.org>
Cc: Green Wan <green.wan@sifive.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230817235859.49846-9-keescook@chromium.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2023-09-28 16:42:14 +05:30
Uwe Kleine-König
3d97deeb3b dmaengine: sf-pdma: sf-pdma: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() is renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230919133207.1400430-39-u.kleine-koenig@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2023-09-28 13:10:54 +05:30
Shravan Chippa
b02e07015a dmaengine: sf-pdma: pdma_desc memory leak fix
Commit b2cc5c465c ("dmaengine: sf-pdma: Add multithread support for a
DMA channel") changed sf_pdma_prep_dma_memcpy() to unconditionally
allocate a new sf_pdma_desc each time it is called.

The driver previously recycled descs, by checking the in_use flag, only
allocating additional descs if the existing one was in use. This logic
was removed in commit b2cc5c465c ("dmaengine: sf-pdma: Add multithread
support for a DMA channel"), but sf_pdma_free_desc() was not changed to
handle the new behaviour.

As a result, each time sf_pdma_prep_dma_memcpy() is called, the previous
descriptor is leaked, over time leading to memory starvation:

  unreferenced object 0xffffffe008447300 (size 192):
  comm "irq/39-mchp_dsc", pid 343, jiffies 4294906910 (age 981.200s)
  hex dump (first 32 bytes):
    00 00 00 ff 00 00 00 00 b8 c1 00 00 00 00 00 00  ................
    00 00 70 08 10 00 00 00 00 00 00 c0 00 00 00 00  ..p.............
  backtrace:
    [<00000000064a04f4>] kmemleak_alloc+0x1e/0x28
    [<00000000018927a7>] kmem_cache_alloc+0x11e/0x178
    [<000000002aea8d16>] sf_pdma_prep_dma_memcpy+0x40/0x112

Add the missing kfree() to sf_pdma_free_desc(), and remove the redundant
in_use flag.

Fixes: b2cc5c465c ("dmaengine: sf-pdma: Add multithread support for a DMA channel")
Signed-off-by: Shravan Chippa <shravan.chippa@microchip.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230120100623.3530634-1-shravan.chippa@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2023-02-16 18:45:48 +05:30
Tudor Ambarus
4b23603a25 dmaengine: drivers: Use devm_platform_ioremap_resource()
platform_get_resource() and devm_ioremap_resource() are wrapped up in the
devm_platform_ioremap_resource() helper. Use the helper and get rid of the
local variable for struct resource *. We now have a function call less.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20221110152528.7821-1-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2023-01-18 22:16:47 +05:30
ye xingchen
7d81afd269 dmaengine: sf-pdma:Remove the print function dev_err()
>From the coccinelle check:

./drivers/dma/sf-pdma/sf-pdma.c
Error:line 409 is redundant because platform_get_irq() already prints an
error

./drivers/dma/sf-pdma/sf-pdma.c
Error:line 424 is redundant because platform_get_irq() already prints an
error

So,remove the unnecessary print function dev_err()

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Link: https://lore.kernel.org/r/20220810062532.13425-1-ye.xingchen@zte.com.cn
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-05 11:50:38 +05:30
Viacheslav Mitrofanov
b2cc5c465c dmaengine: sf-pdma: Add multithread support for a DMA channel
When we get a DMA channel and try to use it in multiple threads it
will cause oops and hanging the system.

% echo 64 > /sys/module/dmatest/parameters/threads_per_chan
% echo 10000 > /sys/module/dmatest/parameters/iterations
% echo 1 > /sys/module/dmatest/parameters/run
[   89.480664] Unable to handle kernel NULL pointer dereference at virtual
               address 00000000000000a0
[   89.488725] Oops [#1]
[   89.494708] CPU: 2 PID: 1008 Comm: dma0chan0-copy0 Not tainted
               5.17.0-rc5
[   89.509385] epc : vchan_find_desc+0x32/0x46
[   89.513553]  ra : sf_pdma_tx_status+0xca/0xd6

This happens because of data race. Each thread rewrite channels's
descriptor as soon as device_prep_dma_memcpy() is called. It leads to the
situation when the driver thinks that it uses right descriptor that
actually is freed or substituted for other one.

With current fixes a descriptor changes its value only when it has
been used. A new descriptor is acquired from vc->desc_issued queue that
is already filled with descriptors that are ready to be sent. Threads
have no direct access to DMA channel descriptor. Now it is just possible
to queue a descriptor for further processing.

Fixes: 6973886ad5 ("dmaengine: sf-pdma: add platform DMA support for HiFive Unleashed A00")
Signed-off-by: Viacheslav Mitrofanov <v.v.mitrofanov@yadro.com>
Link: https://lore.kernel.org/r/20220701082942.12835-1-v.v.mitrofanov@yadro.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-07-06 18:10:34 +05:30
Zong Li
e2dfce24f4 dmaengine: sf-pdma: Get number of channel by device tree
It currently assumes that there are always four channels, it would
cause the error if there is actually less than four channels. Change
that by getting number of channel from device tree.

For backwards-compatibility, it uses the default value (i.e. 4) when
there is no 'dma-channels' information in dts.

Signed-off-by: Zong Li <zong.li@sifive.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Link: https://lore.kernel.org/r/f08a95b6582a51712c5b2c3cb859136d07bfa8b9.1648461096.git.zong.li@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-04-08 18:43:29 +05:30
Linus Torvalds
18ef082713 dmaengine updates for v5.14-rc1
New drivers/devices
  - Support for QCOM SM8250 GPI DMA
  - removal of shdma-of driver and binding
 
 Updates:
  - arm-pl08x yaml binding move
  - altera-msgdma gained DT support
  - removal of imx-sdma platform data support
  - idxd and xilinx driver updates
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Merge tag 'dmaengine-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine

Pull dmaengine updates from Vinod Koul:
 "This time around we have a smaller pull request than usual and this
  includes code removal, so should be good!

  New drivers/devices
   - Support for QCOM SM8250 GPI DMA
   - removal of shdma-of driver and binding

  Updates:
   - arm-pl08x yaml binding move
   - altera-msgdma gained DT support
   - removal of imx-sdma platform data support
   - idxd and xilinx driver updates"

* tag 'dmaengine-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (22 commits)
  dmaengine: imx-sdma: Remove platform data header
  dmaengine: xilinx: dpdma: Fix spacing around addr[i-1]
  dmaengine: xilinx: dpdma: Use kernel type u32 over uint32_t
  dmaengine: altera-msgdma: add OF support
  MAINTAINERS: add entry for Altera mSGDMA
  dt-bindings: dma: add schema for altera-msgdma
  dmaengine: xilinx: dpdma: fix kernel-doc
  dmaengine: sf-pdma: apply proper spinlock flags in sf_pdma_prep_dma_memcpy()
  dmaengine: sh: Remove unused shdma-of driver
  dt-bindings: dmaengine: Remove SHDMA Device Tree bindings
  dmaengine: qcom: gpi: Add SM8250 compatible
  dt-bindings: dmaengine: qcom: gpi: add compatible for sm8250
  dmaengine: sun4i: Use list_move_tail instead of list_del/list_add_tail
  dmaengine: ti: omap-dma: Skip pointless cpu_pm context restore on errors
  dmaengine: hsu: Account transferred bytes
  dmaengine: Move kdoc description of struct dma_chan_percpu closer to it
  dmaengine: xilinx: dpdma: Print debug message when losing vsync race
  dmaengine: xilinx: dpdma: Print channel number in kernel log messages
  dt-bindings: dma: convert arm-pl08x to yaml
  dmaengine: idxd: remove devm allocation for idxd->int_handles
  ...
2021-07-05 12:05:13 -07:00
Austin Kim
94b4cd7c5f dmaengine: sf-pdma: apply proper spinlock flags in sf_pdma_prep_dma_memcpy()
The second parameter of spinlock_irq[save/restore] function is flags,
which is the last input parameter of sf_pdma_prep_dma_memcpy().

So declare local variable 'iflags' to be used as the second parameter of
spinlock_irq[save/restore] function.

Signed-off-by: Austin Kim <austin.kim@lge.com>
Link: https://lore.kernel.org/r/20210611065336.GA1121@raspberrypi
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-06-16 16:10:00 +05:30
Randy Dunlap
8e2e4f3c58 dmaengine: SF_PDMA depends on HAS_IOMEM
When CONFIG_HAS_IOMEM is not set/enabled, certain iomap() family
functions [including ioremap(), devm_ioremap(), etc.] are not
available.
Drivers that use these functions should depend on HAS_IOMEM so that
they do not cause build errors.

Mends this build error:
s390-linux-ld: drivers/dma/sf-pdma/sf-pdma.o: in function `sf_pdma_probe':
sf-pdma.c:(.text+0x1668): undefined reference to `devm_ioremap_resource'

Fixes: 6973886ad5 ("dmaengine: sf-pdma: add platform DMA support for HiFive Unleashed A00")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Green Wan <green.wan@sifive.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: dmaengine@vger.kernel.org
Link: https://lore.kernel.org/r/20210522021313.16405-4-rdunlap@infradead.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-05-31 09:44:14 +05:30
Krzysztof Kozlowski
75fa2d4218 dmaengine: sf: drop of_match_ptr from of_device_id table
The driver can match only via the DT table so the table should be always
used and the of_match_ptr does not have any sense (this also allows ACPI
matching via PRP0001, even though it is not relevant here).  This fixes
compile warning (!CONFIG_OF on x86_64):

    drivers/dma/sf-pdma/sf-pdma.c:576:34: warning:
        ‘sf_pdma_dt_ids’ defined but not used [-Wunused-const-variable=]

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201120162303.482126-4-krzk@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-11-24 23:02:20 +05:30
Barry Song
302b3b3823 dmaengine: sf-pdma: remove redundant irqsave and irqrestore in hardIRQ
Running in hardIRQ, disabling IRQ is redundant since hardIRQ has disabled
IRQ. This patch removes the irqsave and irqstore to save some instruction
cycles.

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Cc: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20201027215252.25820-4-song.bao.hua@hisilicon.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-11-09 17:25:54 +05:30
Allen Pais
1311f7c7d9 dmaengine: sf-pdma: convert tasklets to use new tasklet_setup() API
In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.

Signed-off-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Allen Pais <apais@linux.microsoft.com>
Link: https://lore.kernel.org/r/20201006050458.221329-1-allen.lkml@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-10-07 15:22:09 +05:30
Vinod Koul
d8344fa93e dmaengine: sf-pdma: remove unused 'desc'
'desc' variable is now defined but not used in sf_pdma_donebh_tasklet(),
causing this warning:

drivers/dma/sf-pdma/sf-pdma.c: In function 'sf_pdma_donebh_tasklet':
drivers/dma/sf-pdma/sf-pdma.c:287:23: warning: unused variable 'desc' [-Wunused-variable]

Remove this unused variable

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20200914055302.22962-1-vkoul@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-09-18 12:30:53 +05:30
Brad Kim
8f6b6d0606 dmaengine: sf-pdma: Fix an error that calls callback twice
Because a callback is called twice when DMA transfer complete
the second callback may be possible to access a freed memory
if the first callback routines perform the dma_release_channel function.
So this patch serialized the callback functions

Signed-off-by: Brad Kim <brad.kim@semifive.com>
Tested-and-reviewed-by: Green Wan <green.wan@sifive.com>
Signed-off-by: Brad Kim <brad.kim@sifive.com>
Link: https://lore.kernel.org/r/20200903111726.3413-1-brad.kim@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-09-11 17:39:53 +05:30
Herbert Xu
7999096fa9 iov_iter: Move unnecessary inclusion of crypto/hash.h
The header file linux/uio.h includes crypto/hash.h which pulls in
most of the Crypto API.  Since linux/uio.h is used throughout the
kernel this means that every tiny bit of change to the Crypto API
causes the entire kernel to get rebuilt.

This patch fixes this by moving it into lib/iov_iter.c instead
where it is actually used.

This patch also fixes the ifdef to use CRYPTO_HASH instead of just
CRYPTO which does not guarantee the existence of ahash.

Unfortunately a number of drivers were relying on linux/uio.h to
provide access to linux/slab.h.  This patch adds inclusions of
linux/slab.h as detected by build failures.

Also skbuff.h was relying on this to provide a declaration for
ahash_request.  This patch adds a forward declaration instead.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-06-30 09:34:23 -04:00
Christophe JAILLET
f2b5d503c0 dmaengine: sf-pdma: Simplify the error handling path in 'sf_pdma_probe()'
There is no need to explicitly free memory that have been 'devm_kzalloc'ed.
Simplify the probe function accordingly.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Tested-by: Green Wan <green.wan@sifive.com>
Reviewed-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20200501100824.126534-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-05-13 17:07:50 +05:30
Sascha Hauer
51fe9cd2bd dmaengine: virt-dma: Add missing locking
Originally freeing descriptors was split into a locked and an unlocked
part. The locked part in vchan_get_all_descriptors() collected all
descriptors on a separate list_head. This was done to allow iterating
over that new list in vchan_dma_desc_free_list() without a lock held.

This became broken in 13bb26ae88 ("dmaengine: virt-dma: don't always
free descriptor upon completion"). With this commit
vchan_dma_desc_free_list() no longer exclusively operates on the
separate list, but starts to put descriptors which can be reused back on
&vc->desc_allocated. This list operation should have been locked, but
wasn't.
In the mean time drivers started to call vchan_dma_desc_free_list() with
their lock held so that we now have the situation that
vchan_dma_desc_free_list() is called locked from some drivers and
unlocked from others.
To clean this up we have to do two things:

1. Add missing locking in vchan_dma_desc_free_list()
2. Make sure drivers call vchan_dma_desc_free_list() unlocked

This needs to be done atomically, so in this patch the locking is added
and all drivers are fixed.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Green Wan <green.wan@sifive.com>
Tested-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191216105328.15198-3-s.hauer@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-26 10:04:18 +05:30
Green Wan
7d268a28ee dmaengine: sf-pdma: move macro to header file
The place where the macro, SF_PDMA_REG_BASE(), is cause kernel-doc
using wrong function declaration. Move it to header file.

Signed-off-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191118143554.16129-2-green.wan@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-11-22 11:15:28 +05:30
Green Wan
dd9c324a5e dmaengine: sf-pdma: replace /** with /* for non-function comment
There are several comments starting from "/**" but not for function
comment purpose. It causes kernel-doc parsing wrong string. Replace
"/**" with "/*" to fix them.

Signed-off-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191118143554.16129-1-green.wan@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-11-22 11:15:28 +05:30
Green Wan
6973886ad5 dmaengine: sf-pdma: add platform DMA support for HiFive Unleashed A00
Add PDMA driver, sf-pdma, to enable DMA engine on HiFive Unleashed
Rev A00 board.

 - Implement dmaengine APIs, support MEM_TO_MEM async copy.
 - Tested by DMA Test client
 - Supports 4 channels DMA, each channel has 1 done and 1 err
   interrupt connected to platform-level interrupt controller (PLIC).
 - Depends on DMA_ENGINE and DMA_VIRTUAL_CHANNELS

The datasheet is here:

  https://static.dev.sifive.com/FU540-C000-v1.0.pdf

Follow the DMAengine controller doc,
"./Documentation/driver-api/dmaengine/provider.rst" to implement DMA
engine. And use the dma test client in doc,
"./Documentation/driver-api/dmaengine/dmatest.rst", to test.

Each DMA channel has separate HW regs and support done and error ISRs.
4 channels share 1 done and 1 err ISRs. There's no expander/arbitrator
in DMA HW.

   ------               ------
   |    |--< done 23 >--|ch 0|
   |    |--< err  24 >--|    |     (dma0chan0)
   |    |               ------
   |    |               ------
   |    |--< done 25 >--|ch 1|
   |    |--< err  26 >--|    |     (dma0chan1)
   |PLIC|               ------
   |    |               ------
   |    |--< done 27 >--|ch 2|
   |    |--< err  28 >--|    |     (dma0chan2)
   |    |               ------
   |    |               ------
   |    |--< done 29 >--|ch 3|
   |    |--< err  30 >--|    |     (dma0chan3)
   ------               ------

Signed-off-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191107084955.7580-4-green.wan@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-11-14 12:40:46 +05:30