linux-toradex.git/drivers/dma/fsldma.c, branch v4.0.2

dmaengine: fsldma: remove the unused variable

2015-01-13T18:28:08+00:00

Fix the following build warning:
  drivers/dma/fsldma.c: In function 'fsl_dma_device_terminate_all':
  drivers/dma/fsldma.c:947:6: warning: unused variable 'size' [-Wunused-variable]

Signed-off-by: Kevin Hao 
Signed-off-by: Vinod Koul

dmaengine: fsldma: declare slave capabilities for the generic code

2015-01-13T18:28:08+00:00

Since commit ecc19d17868b ("dmaengine: Add a warning for drivers not
using the generic slave caps retrieval"), the dma drivers are required
to fill the caps infos in order to support generic slaves caps
retrieval. Otherwise we will get a warning like this:
  WARNING: at drivers/dma/dmaengine.c:830
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W       3.19.0-rc2-next-20150106-dirty #271
  task: c0000001f70a0000 ti: c0000001f7044000 task.ti: c0000001f7044000
  NIP: c00000000032b238 LR: c00000000032b234 CTR: c00000000001d258
  REGS: c0000001f7047330 TRAP: 0700   Tainted: G        W        (3.19.0-rc2-next-20150106-dirty)
  MSR: 0000000080029000   CR: 24adbe22  XER: 20000000
  SOFTE: 1
  GPR00: c00000000032b234 c0000001f70475b0 c0000000009b4848 0000000000000040
  GPR04: 0000000000000001 0000000000000001 0000000000000000 000000000000000f
  GPR08: 0000000000000000 c000000000902988 c000000000902988 00000000000052c8
  GPR12: 0000000024adbe22 c00000000fff4000 c000000000002038 0000000000000000
  GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR24: 0000000000000000 0000000000000000 c000000000972dc8 c0000000007e6fd0
  GPR28: c0000001f76d1d30 c0000001f76d1c10 c0000001f76d1c00 0000000000000000
  NIP [c00000000032b238] .dma_async_device_register+0x3f8/0x5b8
  LR [c00000000032b234] .dma_async_device_register+0x3f4/0x5b8
  Call Trace:
  [c0000001f70475b0] [c00000000032b234] .dma_async_device_register+0x3f4/0x5b8 (unreliable)
  [c0000001f70476a0] [c00000000032ca78] .fsldma_of_probe+0x298/0x438
  [c0000001f7047750] [c00000000037080c] .platform_drv_probe+0x50/0x9c
  [c0000001f70477d0] [c00000000036e74c] .really_probe+0xa4/0x29c
  [c0000001f7047870] [c00000000036eae4] .__driver_attach+0x100/0x104
  [c0000001f7047900] [c00000000036c1f0] .bus_for_each_dev+0x84/0xe4
  [c0000001f70479a0] [c00000000036e164] .driver_attach+0x24/0x38
  [c0000001f7047a10] [c00000000036dcc8] .bus_add_driver+0x1c8/0x2ac
  [c0000001f7047ab0] [c00000000036f14c] .driver_register+0x8c/0x158
  [c0000001f7047b30] [c0000000003707a8] .__platform_driver_register+0x6c/0x80
  [c0000001f7047ba0] [c000000000898a3c] .fsldma_init+0x2c/0x40
  [c0000001f7047c10] [c000000000001818] .do_one_initcall+0xb8/0x234
  [c0000001f7047d00] [c000000000878e2c] .kernel_init_freeable+0x188/0x268
  [c0000001f7047db0] [c000000000002054] .kernel_init+0x1c/0xfc8
  [c0000001f7047e30] [c000000000000884] .ret_from_kernel_thread+0x58/0xd4
  Instruction dump:
  7fb9f840 3bffffe0 409effac 7f54d378 48000060 813d0050 2f890000 40befdd0
  3c62ffe3 38632450 482f0aa9 60000000 <0fe00000> 4bfffdb8 7f03c378 482ed465

Signed-off-by: Kevin Hao 
Signed-off-by: Vinod Koul

dmaengine: fsl-dma: Split device_control

2014-12-22T06:59:03+00:00

Split the device_control callback of the Freescale Elo DMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

While we're at it, remove the useless prep_sg callback.

Signed-off-by: Maxime Ripard 
Signed-off-by: Vinod Koul

Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2014-12-15T00:10:09+00:00

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev__once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...

dmaengine: fsldma: Remove chancnt affectations

2014-11-06T06:02:45+00:00

chanctnt is already filled by dma_async_device_register, which uses the channel
list to know how much channels there is.

Since it's already filled, we can safely remove it from the drivers' probe
function.

Signed-off-by: Maxime Ripard 
Signed-off-by: Vinod Koul

dma: drop owner assignment from platform_drivers

2014-10-20T14:20:28+00:00

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang

dmaengine: freescale: remove FSLDMA_EXTERNAL_START control method

2014-10-15T16:01:28+00:00

since users have been move to fsl_dma_external_start() API, so remove this
now

Signed-off-by: Vinod Koul

dmaengine: freescale: add and export fsl_dma_external_start()

2014-10-15T16:01:27+00:00

The freescale driver uses custom device control FSLDMA_EXTERNAL_START to
put the controller in external start mode.
Since we are planning to deprecate the device control, move this to exported
API. Subsequent patches will remove the FSLDMA_EXTERNAL_START

Signed-off-by: Vinod Koul

dmaengine: Freescale: change descriptor release process for supporting async_tx

2014-07-14T16:02:18+00:00

Fix the potential risk when enable config NET_DMA and ASYNC_TX. Async_tx is
lack of support in current release process of dma descriptor, all descriptors
will be released whatever is acked or no-acked by async_tx, so there is a
potential race condition when dma engine is uesd by others clients (e.g. when
enable NET_DMA to offload TCP).

In our case, a race condition which is raised when use both of talitos and
dmaengine to offload xor is because napi scheduler will sync all pending
requests in dma channels, it affects the process of raid operations due to
ack_tx is not checked in fsl dma. The no-acked descriptor is freed which is
submitted just now, as a dependent tx, this freed descriptor trigger
BUG_ON(async_tx_test_ack(depend_tx)) in async_tx_submit().

TASK = ee1a94a0[1390] 'md0_raid5' THREAD: ecf40000 CPU: 0
GPR00: 00000001 ecf41ca0 ee44/921a94a0 0000003f 00000001 c00593e4 00000000 00000001
GPR08: 00000000 a7a7a7a7 00000001 045/920000002 42028042 100a38d4 ed576d98 00000000
GPR16: ed5a11b0 00000000 2b162000 00000200 046/920000000 2d555000 ed3015e8 c15a7aa0
GPR24: 00000000 c155fc40 00000000 ecb63220 ecf41d28 e47/92f640bb0 ef640c30 ecf41ca0
NIP [c02b048c] async_tx_submit+0x6c/0x2b4
LR [c02b068c] async_tx_submit+0x26c/0x2b4
Call Trace:
[ecf41ca0] [c02b068c] async_tx_submit+0x26c/0x2b448/92 (unreliable)
[ecf41cd0] [c02b0a4c] async_memcpy+0x240/0x25c
[ecf41d20] [c0421064] async_copy_data+0xa0/0x17c
[ecf41d70] [c0421cf4] __raid_run_ops+0x874/0xe10
[ecf41df0] [c0426ee4] handle_stripe+0x820/0x25e8
[ecf41e90] [c0429080] raid5d+0x3d4/0x5b4
[ecf41f40] [c04329b8] md_thread+0x138/0x16c
[ecf41f90] [c008277c] kthread+0x8c/0x90
[ecf41ff0] [c0011630] kernel_thread+0x4c/0x68

Another modification in this patch is the change of completed descriptors,
there is a potential risk which caused by exception interrupt, all descriptors
in ld_running list are seemed completed when an interrupt raised, it works fine
under normal condition, but if there is an exception occured, it cannot work as
our excepted. Hardware should not be depend on s/w list, the right way is to
read current descriptor address register to find the last completed descriptor.
If an interrupt is raised by an error, all descriptors in ld_running should not
be seemed finished, or these unfinished descriptors in ld_running will be
released wrongly.

A simple way to reproduce:
Enable dmatest first, then insert some bad descriptors which can trigger
Programming Error interrupts before the good descriptors. Last, the good
descriptors will be freed before they are processsed because of the exception
intrerrupt.

Note: the bad descriptors are only for simulating an exception interrupt.  This
case can illustrate the potential risk in current fsl-dma very well.

Signed-off-by: Hongbo Zhang 
Signed-off-by: Qiang Liu 
Signed-off-by: Ira W. Snyder 
Signed-off-by: Vinod Koul

dmaengine: Freescale: add suspend resume functions for DMA driver

2014-07-14T16:02:18+00:00

This patch adds suspend and resume functions for Freescale DMA driver.

Signed-off-by: Hongbo Zhang 
Signed-off-by: Vinod Koul