Commit graph

23 commits

Author SHA1 Message Date
Guillaume Ranquet
9041575348 dmaengine: mediatek: use GFP_NOWAIT instead of GFP_ATOMIC in prep_dma
As recommended by the doc in:
Documentation/drivers-api/dmaengine/provider.rst

Use GFP_NOWAIT to not deplete the emergency pool.

Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>

Link: https://lore.kernel.org/r/20210513192642.29446-4-granquet@baylibre.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-06-07 12:23:47 +05:30
Guillaume Ranquet
2537b40b0a dmaengine: mediatek: do not issue a new desc if one is still current
Avoid issuing a new desc if one is still being processed as this can
lead to some desc never being marked as completed.

Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>

Link: https://lore.kernel.org/r/20210513192642.29446-3-granquet@baylibre.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-06-07 12:23:47 +05:30
Guillaume Ranquet
0a2ff58f9f dmaengine: mediatek: free the proper desc in desc_free handler
The desc_free handler assumed that the desc we want to free was always
 the current one associated with the channel.

This is seldom the case and this is causing use after free crashes in
 multiple places (tx/rx/terminate...).

  BUG: KASAN: use-after-free in mtk_uart_apdma_rx_handler+0x120/0x304

  Call trace:
   dump_backtrace+0x0/0x1b0
   show_stack+0x24/0x34
   dump_stack+0xe0/0x150
   print_address_description+0x8c/0x55c
   __kasan_report+0x1b8/0x218
   kasan_report+0x14/0x20
   __asan_load4+0x98/0x9c
   mtk_uart_apdma_rx_handler+0x120/0x304
   mtk_uart_apdma_irq_handler+0x50/0x80
   __handle_irq_event_percpu+0xe0/0x210
   handle_irq_event+0x8c/0x184
   handle_fasteoi_irq+0x1d8/0x3ac
   __handle_domain_irq+0xb0/0x110
   gic_handle_irq+0x50/0xb8
   el0_irq_naked+0x60/0x6c

  Allocated by task 3541:
   __kasan_kmalloc+0xf0/0x1b0
   kasan_kmalloc+0x10/0x1c
   kmem_cache_alloc_trace+0x90/0x2dc
   mtk_uart_apdma_prep_slave_sg+0x6c/0x1a0
   mtk8250_dma_rx_complete+0x220/0x2e4
   vchan_complete+0x290/0x340
   tasklet_action_common+0x220/0x298
   tasklet_action+0x28/0x34
   __do_softirq+0x158/0x35c

  Freed by task 3541:
   __kasan_slab_free+0x154/0x224
   kasan_slab_free+0x14/0x24
   slab_free_freelist_hook+0xf8/0x15c
   kfree+0xb4/0x278
   mtk_uart_apdma_desc_free+0x34/0x44
   vchan_complete+0x1bc/0x340
   tasklet_action_common+0x220/0x298
   tasklet_action+0x28/0x34
   __do_softirq+0x158/0x35c

  The buggy address belongs to the object at ffff000063606800
   which belongs to the cache kmalloc-256 of size 256
  The buggy address is located 176 bytes inside of
   256-byte region [ffff000063606800, ffff000063606900)
  The buggy address belongs to the page:
  page:fffffe00016d8180 refcount:1 mapcount:0 mapping:ffff00000302f600 index:0x0 compound_mapcount: 0
  flags: 0xffff00000010200(slab|head)
  raw: 0ffff00000010200 dead000000000100 dead000000000122 ffff00000302f600
  raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
  page dumped because: kasan: bad access detected

Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>

Link: https://lore.kernel.org/r/20210513192642.29446-2-granquet@baylibre.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-06-07 12:23:47 +05:30
Christophe JAILLET
33cbd54dc5 dmaengine: mediatek: mtk-hsdma: Fix a resource leak in the error handling path of the probe function
'mtk_hsdma_hw_deinit()' should be called in the error handling path of the
probe function to undo a previous 'mtk_hsdma_hw_init()' call, as already
done in the remove function.

Fixes: 548c4597e9 ("dmaengine: mediatek: Add MediaTek High-Speed DMA controller for MT7622 and MT7623 SoC")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20201219124718.182664-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-12-29 10:07:59 +05:30
Vinod Koul
a841592fb3 Merge branch 'topic/tasklet' into next 2020-10-01 10:18:59 +05:30
Liu Shixin
ceae069803 dmaengine: mediatek: simplify the return expression of mtk_uart_apdma_runtime_resume()
Simplify the return expression.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Link: https://lore.kernel.org/r/20200915032622.1772309-1-liushixin2@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-09-18 12:32:37 +05:30
Allen Pais
80ef88693e dmaengine: mediatek: 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 <allen.lkml@gmail.com>
Link: https://lore.kernel.org/r/20200831103542.305571-14-allen.lkml@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-09-18 12:19:06 +05:30
Lee Jones
f4c20f084d dmaengine: mediatek: mtk-hsdma: Fix formatting in 'struct mtk_hsdma_pdesc' doc block
Struct attribute names must be an exact match or the kerneldoc checker
gets confused.

Fixes the following W=1 kernel build warning(s):

 drivers/dma/mediatek/mtk-hsdma.c:120: warning: Function parameter or member 'desc1' not described in 'mtk_hsdma_pdesc'
 drivers/dma/mediatek/mtk-hsdma.c:120: warning: Function parameter or member 'desc2' not described in 'mtk_hsdma_pdesc'
 drivers/dma/mediatek/mtk-hsdma.c:120: warning: Function parameter or member 'desc3' not described in 'mtk_hsdma_pdesc'
 drivers/dma/mediatek/mtk-hsdma.c:120: warning: Function parameter or member 'desc4' not described in 'mtk_hsdma_pdesc'

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Cc: Sean Wang <sean.wang@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: linux-mediatek@lists.infradead.org
Link: https://lore.kernel.org/r/20200714111546.1755231-2-lee.jones@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-07-15 17:50:46 +05:30
Masahiro Yamada
a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
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
Satendra Singh Thakur
1ff9524325 dmaengine: mediatek: hsdma_probe: fixed a memory leak when devm_request_irq fails
When devm_request_irq fails, currently, the function
dma_async_device_unregister gets called. This doesn't free
the resources allocated by of_dma_controller_register.
Therefore, we have called of_dma_controller_free for this purpose.

Signed-off-by: Satendra Singh Thakur <sst2005@gmail.com>
Link: https://lore.kernel.org/r/20191109113523.6067-1-sst2005@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-11-14 12:16:53 +05:30
Markus Elfring
a7dc0e6c1e dmaengine: mediatek: Use devm_platform_ioremap_resource() in mtk_uart_apdma_probe()
Simplify this function implementation by using a known wrapper function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Link: https://lore.kernel.org/r/366e776c-8760-eeb7-c248-7380c9f4fd34@web.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-14 13:21:20 +05:30
Markus Elfring
9d68427d0f dmaengine: mediatek: Use devm_platform_ioremap_resource() in mtk_cqdma_probe()
Simplify this function implementation a bit by using
a known wrapper function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Link: https://lore.kernel.org/r/c7e3bbae-44fa-9019-18ee-c6cdfd7c2a14@web.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-10-14 13:21:20 +05:30
Stephen Boyd
e17be6e1b7 dmaengine: Remove dev_err() usage after platform_get_irq()
We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: Vinod Koul <vkoul@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: dmaengine@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20190730181557.90391-11-swboyd@chromium.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-07-31 20:50:53 +05:30
Linus Torvalds
47ebe00b68 dmaengine updates for v5.3-rc1
- Add support in dmaengine core to do device node checks for DT devices and
    update bunch of drivers to use that and remove open coding from drivers
  - New driver/driver support for new hardware, namely:
    - MediaTek UART APDMA
    - Freescale i.mx7ulp edma2
    - Synopsys eDMA IP core version 0
    - Allwinner H6 DMA
  - Updates to axi-dma and support for interleaved cyclic transfers
  - Greg's debugfs return value check removals on drivers
  - Updates to stm32-dma, hsu, dw, pl330, tegra drivers
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Merge tag 'dmaengine-5.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine updates from Vinod Koul:

 - Add support in dmaengine core to do device node checks for DT devices
   and update bunch of drivers to use that and remove open coding from
   drivers

 - New driver/driver support for new hardware, namely:
     - MediaTek UART APDMA
     - Freescale i.mx7ulp edma2
     - Synopsys eDMA IP core version 0
     - Allwinner H6 DMA

 - Updates to axi-dma and support for interleaved cyclic transfers

 - Greg's debugfs return value check removals on drivers

 - Updates to stm32-dma, hsu, dw, pl330, tegra drivers

* tag 'dmaengine-5.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (68 commits)
  dmaengine: Revert "dmaengine: fsl-edma: add i.mx7ulp edma2 version support"
  dmaengine: at_xdmac: check for non-empty xfers_list before invoking callback
  Documentation: dmaengine: clean up description of dmatest usage
  dmaengine: tegra210-adma: remove PM_CLK dependency
  dmaengine: fsl-edma: add i.mx7ulp edma2 version support
  dt-bindings: dma: fsl-edma: add new i.mx7ulp-edma
  dmaengine: fsl-edma-common: version check for v2 instead
  dmaengine: fsl-edma-common: move dmamux register to another single function
  dmaengine: fsl-edma: add drvdata for fsl-edma
  dmaengine: Revert "dmaengine: fsl-edma: support little endian for edma driver"
  dmaengine: rcar-dmac: Reject zero-length slave DMA requests
  dmaengine: dw: Enable iDMA 32-bit on Intel Elkhart Lake
  dmaengine: dw-edma: fix semicolon.cocci warnings
  dmaengine: sh: usb-dmac: Use [] to denote a flexible array member
  dmaengine: dmatest: timeout value of -1 should specify infinite wait
  dmaengine: dw: Distinguish ->remove() between DW and iDMA 32-bit
  dmaengine: fsl-edma: support little endian for edma driver
  dmaengine: hsu: Revert "set HSU_CH_MTSR to memory width"
  dmagengine: pl330: add code to get reset property
  dt-bindings: pl330: document the optional resets property
  ...
2019-07-17 09:55:43 -07:00
Linus Torvalds
66b59f2b5e dmaengine fixes for v5.2-rc4
The fixes for this round are in drivers:
  - jz4780 transfer fix for acking descriptors early
  - fsl-qdma: clean registers on error
  - dw-axi-dmac: null pointer dereference fix
  - mediatek-cqdma: fix sleeping in atomic context
  - tegra210-adma: fix bunch os issues like crashing in driver
    probe, channel FIFO configuration etc.
  - sprd: Fixes for possible crash on descriptor status, block
    length overflow. For 2-stage transfer fix incorrect start,
    configuration and interrupt handling.
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Merge tag 'dmaengine-fix-5.2-rc4' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine fixes from Vinod Koul:

 - jz4780 transfer fix for acking descriptors early

 - fsl-qdma: clean registers on error

 - dw-axi-dmac: null pointer dereference fix

 - mediatek-cqdma: fix sleeping in atomic context

 - tegra210-adma: fix bunch os issues like crashing in driver probe,
   channel FIFO configuration etc.

 - sprd: Fixes for possible crash on descriptor status, block length
   overflow. For 2-stage transfer fix incorrect start, configuration and
   interrupt handling.

* tag 'dmaengine-fix-5.2-rc4' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: sprd: Add interrupt support for 2-stage transfer
  dmaengine: sprd: Fix the right place to configure 2-stage transfer
  dmaengine: sprd: Fix block length overflow
  dmaengine: sprd: Fix the incorrect start for 2-stage destination channels
  dmaengine: sprd: Add validation of current descriptor in irq handler
  dmaengine: sprd: Fix the possible crash when getting descriptor status
  dmaengine: tegra210-adma: Fix spelling
  dmaengine: tegra210-adma: Fix channel FIFO configuration
  dmaengine: tegra210-adma: Fix crash during probe
  dmaengine: mediatek-cqdma: sleeping in atomic context
  dmaengine: dw-axi-dmac: fix null dereference when pointer first is null
  dmaengine: fsl-qdma: Add improvement
  dmaengine: jz4780: Fix transfers being ACKed too soon
2019-06-08 12:46:31 -07:00
Long Cheng
9135408c3a dmaengine: mediatek: Add MediaTek UART APDMA support
Add 8250 UART APDMA to support MediaTek UART. If MediaTek UART is
enabled by SERIAL_8250_MT6577, and we can enable this driver to offload
the UART device moving bytes.

Signed-off-by: Long Cheng <long.cheng@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-06-07 15:36:45 +05:30
Dan Carpenter
069b3c4214 dmaengine: mediatek-cqdma: sleeping in atomic context
The mtk_cqdma_poll_engine_done() function takes a true/false parameter
where true means it's called from atomic context.  There are a couple
places where it was set to false but it's actually in atomic context
so it should be true.

All the callers for mtk_cqdma_hard_reset() are holding a spin_lock and
in mtk_cqdma_free_chan_resources() we take a spin_lock before calling
the mtk_cqdma_poll_engine_done() function.

Fixes: b1f01e48df ("dmaengine: mediatek: Add MediaTek Command-Queue DMA controller for MT6765 SoC")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-05-21 14:25:59 +05:30
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Shun-Chih Yu
5bb5c3a3ac dmaengine: mediatek-cqdma: fix wrong register usage in mtk_cqdma_start
This patch fixes wrong register usage in the mtk_cqdma_start. The
destination register should be MTK_CQDMA_DST2 instead.

Fixes: b1f01e48df ("dmaengine: mediatek: Add MediaTek Command-Queue DMA controller for MT6765 SoC")
Signed-off-by: Shun-Chih Yu <shun-chih.yu@mediatek.com>
Cc: stable@vger.kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-04-26 17:26:38 +05:30
Luis Chamberlain
750afb08ca cross-tree: phase out dma_zalloc_coherent()
We already need to zero out memory for dma_alloc_coherent(), as such
using dma_zalloc_coherent() is superflous. Phase it out.

This change was generated with the following Coccinelle SmPL patch:

@ replace_dma_zalloc_coherent @
expression dev, size, data, handle, flags;
@@

-dma_zalloc_coherent(dev, size, handle, flags)
+dma_alloc_coherent(dev, size, handle, flags)

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
[hch: re-ran the script on the latest tree]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-01-08 07:58:37 -05:00
Shun-Chih Yu
b1f01e48df dmaengine: mediatek: Add MediaTek Command-Queue DMA controller for MT6765 SoC
MediaTek Command-Queue DMA controller (CQDMA) on MT6765 SoC is dedicated
to memory-to-memory transfer through queue based descriptor management.

There are only 3 physical channels inside CQDMA, while the driver is
extended to support 32 virtual channels for multiple dma users to issue
dma requests onto the CQDMA simultaneously.

Signed-off-by: Shun-Chih Yu <shun-chih.yu@mediatek.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-11-11 15:15:18 +05:30
Sean Wang
548c4597e9 dmaengine: mediatek: Add MediaTek High-Speed DMA controller for MT7622 and MT7623 SoC
MediaTek High-Speed DMA controller (HSDMA) on MT7622 and MT7623 SoC has
a single ring is dedicated to memory-to-memory transfer through ring based
descriptor management.

Even though there is only one physical ring available inside HSDMA, the
driver can be easily extended to the support of multiple virtual channels
processing simultaneously by means of DMA_VIRTUAL_CHANNELS effort.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2018-03-27 15:18:15 +05:30