Commit Graph

59 Commits

Author SHA1 Message Date
Ira Snyder 968f19ae80 fsldma: improved DMA_SLAVE support
Now that the generic DMAEngine API has support for scatterlist to
scatterlist copying, the device_prep_slave_sg() portion of the
DMA_SLAVE API is no longer necessary and has been removed.

However, the device_control() portion of the DMA_SLAVE API is still
useful to control device specific parameters, such as externally
controlled DMA transfers and maximum burst length.

A special dma_ctrl_cmd has been added to enable externally controlled
DMA transfers. This is currently specific to the Freescale DMA
controller, but can easily be made generic when another user is found.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-10-07 14:41:41 -07:00
Ira Snyder c14330417e fsldma: implement support for scatterlist to scatterlist copy
Now that the DMAEngine API has support for scatterlist to scatterlist
copy, implement support for the Freescale DMA controller.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-10-07 14:41:41 -07:00
Grant Likely 2dc1158137 of/device: Replace struct of_device with struct platform_device
of_device is just an alias for platform_device, so remove it entirely.  Also
replace to_of_device() with to_platform_device() and update comment blocks.

This patch was initially generated from the following semantic patch, and then
edited by hand to pick up the bits that coccinelle didn't catch.

@@
@@
-struct of_device
+struct platform_device

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: David S. Miller <davem@davemloft.net>
2010-08-06 09:25:50 -06:00
Stefan Weil c2e07b3a9c Fix spelling contorller -> controller in comments
Cc: Jiri Kosina <trivial@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-08-04 15:05:43 +02:00
Grant Likely cf9b59e9d3 Merge remote branch 'origin' into secretlab/next-devicetree
Merging in current state of Linus' tree to deal with merge conflicts and
build failures in vio.c after merge.

Conflicts:
	drivers/i2c/busses/i2c-cpm.c
	drivers/i2c/busses/i2c-mpc.c
	drivers/net/gianfar.c

Also fixed up one line in arch/powerpc/kernel/vio.c to use the
correct node pointer.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-05-22 00:36:56 -06:00
Grant Likely 4018294b53 of: Remove duplicate fields from of_platform_driver
.name, .match_table and .owner are duplicated in both of_platform_driver
and device_driver.  This patch is a removes the extra copies from struct
of_platform_driver and converts all users to the device_driver members.

This patch is a pretty mechanical change.  The usage model doesn't change
and if any drivers have been missed, or if anything has been fixed up
incorrectly, then it will fail with a compile time error, and the fixup
will be trivial.  This patch looks big and scary because it touches so
many files, but it should be pretty safe.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Sean MacLennan <smaclennan@pikatech.com>
2010-05-22 00:10:40 -06:00
Grant Likely 61c7a080a5 of: Always use 'struct device.of_node' to get device node pointer.
The following structure elements duplicate the information in
'struct device.of_node' and so are being eliminated.  This patch
makes all readers of these elements use device.of_node instead.

(struct of_device *)->node
(struct dev_archdata *)->prom_node (sparc)
(struct dev_archdata *)->of_node (powerpc & microblaze)

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-05-18 16:10:44 -06:00
Dan Williams 0b28330e39 Merge branch 'ioat' into dmaengine 2010-05-17 16:30:58 -07:00
Linus Walleij 058276303d DMAENGINE: extend the control command to include an arg
This adds an argument to the DMAengine control function, so that
we can later provide control commands that need some external data
passed in through an argument akin to the ioctl() operation
prototype.

[dan.j.williams@intel.com: fix up some missed conversions]
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-05-17 16:30:42 -07:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Dan Williams bca3469205 dmaengine: provide helper for setting txstate
Simple conditional struct filler to cut out some duplicated code.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-26 16:52:10 -07:00
Linus Walleij 0793448187 DMAENGINE: generic channel status v2
Convert the device_is_tx_complete() operation on the
DMA engine to a generic device_tx_status()operation which
can return three states, DMA_TX_RUNNING, DMA_TX_COMPLETE,
DMA_TX_PAUSED.

[dan.j.williams@intel.com: update for timberdale]
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Maciej Sosnowski <maciej.sosnowski@intel.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Li Yang <leoli@freescale.com>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Magnus Damm <damm@opensource.se>
Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Joe Perches <joe@perches.com>
Cc: Roland Dreier <rdreier@cisco.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-26 16:50:49 -07:00
Linus Walleij c3635c78e5 DMAENGINE: generic slave control v2
Convert the device_terminate_all() operation on the
DMA engine to a generic device_control() operation
which can now optionally support also pausing and
resuming DMA on a certain channel. Implemented for the
COH 901 318 DMAC as an example.

[dan.j.williams@intel.com: update for timberdale]
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Maciej Sosnowski <maciej.sosnowski@intel.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Li Yang <leoli@freescale.com>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Magnus Damm <damm@opensource.se>
Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Joe Perches <joe@perches.com>
Cc: Roland Dreier <rdreier@cisco.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-03-26 16:44:01 -07:00
Steven J. Magnani 76bd061f5c fsldma: Fix cookie issues
fsl_dma_update_completed_cookie() appears to calculate the last completed
cookie incorrectly in the corner case where DMA on cookie 1 is in progress
just following a cookie wrap.

Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Acked-by: Ira W. Snyder <iws@ovro.caltech.edu>
[dan.j.williams@intel.com: fix an integer overflow warning with INT_MAX]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-28 22:18:16 -07:00
Steven J. Magnani 6ca3a7a96e fsldma: Fix cookie issues
fsl_dma_tx_submit() only sets the cookie on the first descriptor of a
transaction. It should set the cookie on all.

Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Acked-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-28 20:27:42 -07:00
Márton Németh 4b1cf1facc dma: make Open Firmware device id constant
The match_table field of the struct of_device_id is constant in <linux/of_platform.h>
so it is worth to make the initialization data also constant.

The semantic match that finds this kind of pattern is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
disable decl_init,const_decl_init;
identifier I1, I2, x;
@@
	struct I1 {
	  ...
	  const struct I2 *x;
	  ...
	};
@s@
identifier r.I1, y;
identifier r.x, E;
@@
	struct I1 y = {
	  .x = E,
	};
@c@
identifier r.I2;
identifier s.E;
@@
	const struct I2 E[] = ... ;
@depends on !c@
identifier r.I2;
identifier s.E;
@@
+	const
	struct I2 E[] = ...;
// </smpl>

Signed-off-by: Márton Németh <nm127@freemail.hu>
Cc: Julia Lawall <julia@diku.dk>
Cc: cocci@diku.dk
[dan.j.williams@intel.com: resolved conflict with recent fsldma updates]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-02 23:41:06 -07:00
Ira Snyder 9c3a50b7d7 fsldma: major cleanups and fixes
Fix locking. Use two queues in the driver, one for pending transacions, and
one for transactions which are actually running on the hardware. Call
dma_run_dependencies() on descriptor cleanup so that the async_tx API works
correctly.

There are a number of places throughout the code where lists of descriptors
are freed in a loop. Create functions to handle this, and use them instead
of open-coding the loop each time.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-02 14:51:42 -07:00
Ira Snyder a1c0331901 fsldma: rename fsl_chan to chan
The name fsl_chan seems too long, so it has been shortened to chan. There
are only a few places where the higher level "struct dma_chan *chan" name
conflicts. These have been changed to "struct dma_chan *dchan" instead.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-02 14:51:41 -07:00
Ira Snyder d3f620b2c4 fsldma: simplify IRQ probing and handling
The IRQ probing is needlessly complex. All off the 83xx device trees in
arch/powerpc/boot/dts/ specify 5 interrupts per DMA controller: one for the
controller, and one for each channel. These interrupts are all attached to
the same IRQ line.

This causes an interesting situation if two channels interrupt at the same
time. The per-controller handler will handle the first channel, and the
per-channel handler will handle the remaining channels.

Instead of this mess, we fix the bug in the per-controller handler, and
make it handle all channels that generated an interrupt. When a
per-controller handler is specified in the device tree, we prefer to use
the shared handler instead of the per-channel handler.

The 85xx/86xx controllers do not have a per-controller interrupt, and
instead use a per-channel interrupt. This behavior has not been changed.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-02 14:51:41 -07:00
Ira Snyder e7a29151de fsldma: clean up the OF subsystem routines
This fixes some errors in the cleanup paths of the OF subsystem, including
missing checks for ioremap failing. Also, some variables were renamed for
brevity.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-02 14:51:41 -07:00
Ira Snyder 738f5f7e1a fsldma: rename dest to dst for uniformity
Most functions in the standard library use "dst" as a parameter, rather
than "dest". This renames all use of "dest" to "dst" to match the usual
convention.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-02 14:51:41 -07:00
Ira Snyder a4f56d4b10 fsldma: rename struct fsl_dma_chan to struct fsldma_chan
This is the beginning of a cleanup which will change all instances of
"fsl_dma" to "fsldma" to match the name of the driver itself.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-02 14:51:41 -07:00
Ira Snyder 4ce0e953f6 fsldma: remove unused structure members
Remove some unused members from the fsldma data structures. A few trivial
uses of struct resource were converted to use the stack rather than keeping
the memory allocated for the lifetime of the driver.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-02 14:51:40 -07:00
Ira Snyder 272ca65509 fsldma: reduce kernel text size
Some of the functions are written in a way where they use multiple reads
and writes where a single read/write pair could suffice. This shrinks the
kernel text size measurably, while making the functions easier to
understand.

add/remove: 0/0 grow/shrink: 1/4 up/down: 4/-196 (-192)
function                                     old     new   delta
fsl_chan_set_request_count                   120     124      +4
dma_halt                                     300     272     -28
fsl_chan_set_src_loop_size                   208     156     -52
fsl_chan_set_dest_loop_size                  208     156     -52
fsl_chan_xfer_ld_queue                       500     436     -64

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-02 14:51:40 -07:00
Ira Snyder bbea0b6e0d fsldma: Add DMA_SLAVE support
Use the DMA_SLAVE capability of the DMAEngine API to copy/from a
scatterlist into an arbitrary list of hardware address/length pairs.

This allows a single DMA transaction to copy data from several different
devices into a scatterlist at the same time.

This also adds support to enable some controller-specific features such as
external start and external pause for a DMA transaction.

[dan.j.williams@intel.com: rebased on tx_list movement]
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Acked-by: Li Yang <leoli@freescale.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08 17:53:04 -07:00
Ira Snyder e6c7ecb64e fsldma: split apart external pause and request count features
When using the Freescale DMA controller in external control mode, both the
request count and external pause bits need to be setup correctly. This was
being done with the same function.

The 83xx controller lacks the external pause feature, but has a similar
feature called external start. This feature requires that the request count
bits be setup correctly.

Split the function into two parts, to make it possible to use the external
start feature on the 83xx controller.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08 17:53:04 -07:00
Dan Williams eda3423457 fsldma: implement a private tx_list
Drop fsldma's use of tx_list from struct dma_async_tx_descriptor in
preparation for removal of this field.

Cc: Li Yang <leoli@freescale.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08 17:53:02 -07:00
Joe Perches e3d433040e drivers/dma/fsldma.c: Remove unnecessary semicolons
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-07-22 21:29:16 -07:00
Ira Snyder 43a1a3ed6b fsldma: do not clear bandwidth control bits on the 83xx controller
The 83xx controller does not support the external pause feature. The bit
in the mode register that controls external pause on the 85xx controller
happens to be part of the bandwidth control settings for the 83xx
controller.

This patch fixes the driver so that it only clears the external pause bit
if the hardware is the 85xx controller. When driving the 83xx controller,
the bit is left untouched. This follows the existing convention that mode
registers settings are not touched unless necessary.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-06-16 11:43:40 -07:00
Ira Snyder be30b226f2 fsldma: enable external start for the 83xx controller
The 83xx controller has external start capability, but lacks external pause
capability. Hook up the external start function pointer for the 83xx
controller.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-06-16 11:43:00 -07:00
Ira W. Snyder a7aea373b4 fsldma: use PCI Read Multiple command
By default, the Freescale 83xx DMA controller uses the PCI Read Line
command when reading data over the PCI bus. Setting the controller to use
the PCI Read Multiple command instead allows the controller to read much
larger bursts of data, which provides a drastic speed increase.

The slowdown due to using PCI Read Line was only observed when a PCI-to-PCI
bridge was between the devices trying to communicate.

A simple test driver showed an increase from 4MB/sec to 116MB/sec when
performing DMA over the PCI bus. Using DMA to transfer between blocks of
local SDRAM showed no change in performance with this patch. The dmatest
driver was also used to verify the correctness of the transfers, and showed
no errors.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Acked-by: Timur Tabi <timur@freescale.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-06-16 11:29:17 -07:00
Kumar Gala b787f2e2a3 fsldma: Fix compile warnings
We we build with dma_addr_t as a 64-bit quantity we get:

drivers/dma/fsldma.c: In function 'fsl_chan_xfer_ld_queue':
drivers/dma/fsldma.c:625: warning: cast to pointer from integer of different size
drivers/dma/fsldma.c: In function 'fsl_dma_chan_do_interrupt':
drivers/dma/fsldma.c:737: warning: cast to pointer from integer of different size
drivers/dma/fsldma.c:737: warning: cast to pointer from integer of different size
drivers/dma/fsldma.c: In function 'of_fsl_dma_probe':
drivers/dma/fsldma.c:927: warning: cast to pointer from integer of different

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-05-27 13:40:00 -07:00
Ira Snyder 2e077f8e83 fsldma: fix memory leak on error path in fsl_dma_prep_memcpy()
When preparing a memcpy operation, if the kernel fails to allocate memory
for a link descriptor after the first link descriptor has already been
allocated, then some memory will never be released. Fix the problem by
walking the list of allocated descriptors backwards, and freeing the
allocated descriptors back into the DMA pool.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Li Yang <leoli@freescale.com>
2009-05-22 16:54:42 +08:00
Ira Snyder 776c8943f2 fsldma: snooping is not enabled for last entry in descriptor chain
On the 83xx controller, snooping is necessary for the DMA controller to
ensure cache coherence with the CPU when transferring to/from RAM.

The last descriptor in a chain will always have the End-of-Chain interrupt
bit set, so we can set the snoop bit while adding the End-of-Chain
interrupt bit.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Li Yang <leoli@freescale.com>
2009-05-22 16:53:56 +08:00
Ira Snyder bcfb7465c0 fsldma: fix infinite loop on multi-descriptor DMA chain completion
When creating a DMA transaction with multiple descriptors, the async_tx
cookie is set to 0 for each descriptor in the chain, excluding the last
descriptor, whose cookie is set to -EBUSY.

When fsl_dma_tx_submit() is run, it only assigns a cookie to the first
descriptor. All of the remaining descriptors keep their original value,
including the last descriptor, which is set to -EBUSY.

After the DMA completes, the driver will update the last completed cookie
to be -EBUSY, which is an error code instead of a valid cookie. This causes
dma_async_is_complete() to always return DMA_IN_PROGRESS.

This causes the fsldma driver to never cleanup the queue of link
descriptors, and the driver will re-run the DMA transaction on the hardware
each time it receives the End-of-Chain interrupt. This causes an infinite
loop.

With this patch, fsl_dma_tx_submit() is changed to assign a cookie to every
descriptor in the chain. The rest of the code then works without problems.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Li Yang <leoli@freescale.com>
2009-05-22 16:51:28 +08:00
Ira Snyder 138ef01851 fsldma: fix "DMA halt timeout!" errors
When using the DMA controller from multiple threads at the same time, it is
possible to get lots of "DMA halt timeout!" errors printed to the kernel
log.

This occurs due to a race between fsl_dma_memcpy_issue_pending() and the
interrupt handler, fsl_dma_chan_do_interrupt(). Both call the
fsl_chan_xfer_ld_queue() function, which does not protect against
concurrent accesses to dma_halt() and dma_start().

The existing spinlock is moved to cover the dma_halt() and dma_start()
functions. Testing shows that the "DMA halt timeout!" errors disappear.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Li Yang <leoli@freescale.com>
2009-05-22 16:49:17 +08:00
Roel Kluin f47edc6dab fsldma: fix check on potential fdev->chan[] overflow
Fix the check of potential array overflow when using corrupted channel
device tree nodes.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Li Yang <leoli@freescale.com>
2009-05-22 16:46:52 +08:00
Dan Williams ccccce229c dmaengine: initialize tx_list in dma_async_tx_descriptor_init
Centralize this common initialization (and one case where ipu_idmac is
duplicating ->chan initialization).

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-25 09:13:24 -07:00
Dan Williams 900325a6ce fsldma: fix off by one in dma_halt
Prevent dev_err from firing even if we successfully detected 'dma-idle'
before the full 1ms timeout has elapsed.

Acked-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04 16:04:40 -07:00
Peter Korsgaard 169d5f6637 fsldma: print correct IRQ on mpc83xx
The mpc83xx variant uses a shared IRQ for all channels, so the individual
channel nodes don't have an interrupt property. Fix the code to print the
controller IRQ instead if there isn't any for the channel.

Acked-by: Timur Tabi <timur@freescale.com>
Acked-by: Li Yang <leoli@freescale.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-15 23:50:22 -07:00
Peter Korsgaard 6782dfe44a fsldma: check for NO_IRQ in fsl_dma_chan_remove()
There's no per-channel IRQ on mpc83xx, so only call free_irq if we have one.

Acked-by: Timur Tabi <timur@freescale.com>
Acked-by: Li Yang <leoli@freescale.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-14 22:32:58 -07:00
Dan Williams 6527de6d6d fsldma: use a valid 'device' for dma_pool_create
The dmaengine sysfs implementation was fixed to support proper
lifetime rules which means that the current:

new_fsl_chan->dev = &new_fsl_chan->common.dev->device;

...retrieves a NULL pointer because new_fsl_chan->common.dev has not
been allocated at this point.  So, set new_fsl_chan->dev to a valid
device.

Cc: Li Yang <leoli@freescale.com>
Cc: Zhang Wei <zw@zh-kernel.org>
Reported-by: Ira Snyder <iws@ovro.caltech.edu>
Tested-by: Ira Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-12 15:20:42 -07:00
Dan Williams 41d5e59c12 dmaengine: add a release for dma class devices and dependent infrastructure
Resolves:
WARNING: at drivers/base/core.c:122 device_release+0x4d/0x52()
Device 'dma0chan0' does not have a release() function, it is broken and must be fixed.

The dma_chan_dev object is introduced to gear-match sysfs kobject and
dmaengine channel lifetimes.  When a channel is removed access to the
sysfs entries return -ENODEV until the kobject can be released.

The bulk of the change is updates to existing code to handle the extra
layer of indirection between a dma_chan and its struct device.

Reported-by: Alexander Beregalov <a.beregalov@gmail.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06 11:38:21 -07:00
Dan Williams aa1e6f1a38 dmaengine: kill struct dma_client and supporting infrastructure
All users have been converted to either the general-purpose allocator,
dma_find_channel, or dma_request_channel.

Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06 11:38:17 -07:00
Timur Tabi 77cd62e808 fsldma: allow Freescale Elo DMA driver to be compiled as a module
Modify the Freescale Elo / Elo Plus DMA driver so that it can be compiled as
a module.

The primary change is to stop treating the DMA controller as a bus, and the
DMA channels as devices on the bus.  This is because the Open Firmware (OF)
kernel code does not allow busses to be removed, so although we can call
of_platform_bus_probe() to probe the DMA channels, there is no
of_platform_bus_remove().  Instead, the DMA channels are manually probed,
similar to what fsl_elbc_nand.c does.

Cc: Scott Wood <scottwood@freescale.com>
Acked-by: Li Yang <leoli@freescale.com>
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-09-26 17:00:11 -07:00
Timur Tabi 59f647c25a fsldma: remove internal self-test from Freescale Elo DMA driver
The Freescale Elo DMA driver runs an internal self-test before registering
the channels with the DMA engine.  This self-test has a fundemental flaw in
that it calls the DMA engine's callback functions directly before the
registration.  However, the registration initializes some variables that the
callback functions uses, namely the device struct.

The code works today because there are two device structs: the one created
by the DMA engine, and one created by the Open Firmware (OF) subsystem.  The
self-test currently uses the device struct created by OF.  However, in the
future, some of the device structs created by OF will be eliminated.
This means that the self-test will only have access to the device struct
created by the DMA engine.  But this device struct isn't initialized when
the self-test runs, and this causes a kernel panic.

Since there is already a DMA test module (dmatest), the internal self-test
code is not useful anyway.  It is extremely unlikely that the test will fail
in normal usage.  It may have been helpful during development, but not any more.

Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Scott Wood <scottwood@freescale.com>
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-09-23 15:55:56 -07:00
Haavard Skinnemoen 848c536a37 dmaengine: Add dma_client parameter to device_alloc_chan_resources
A DMA controller capable of doing slave transfers may need to know a
few things about the slave when preparing the channel. We don't want
to add this information to struct dma_channel since the channel hasn't
yet been bound to a client at this point.

Instead, pass a reference to the client requesting the channel to the
driver's device_alloc_chan_resources hook so that it can pick the
necessary information from the dma_client struct by itself.

[dan.j.williams@intel.com: fixed up fsldma and mv_xor]
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-07-08 11:58:58 -07:00
Li Yang 51ee87f27a fsldma: fix incorrect exit path for initialization
Signed-off-by: Li Yang <leoli@freescale.com>
Acked-by: Zhang Wei <zw@zh-kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-07-08 11:57:45 -07:00
Dan Williams 636bdeaa12 dmaengine: ack to flags: make use of the unused bits in the 'ack' field
'ack' is currently a simple integer that flags whether or not a client is done
touching fields in the given descriptor.  It is effectively just a single bit
of information.  Converting this to a flags parameter allows the other bits to
be put to use to control completion actions, like dma-unmap, and capture
results, like xor-zero-sum == 0.

Changes are one of:
1/ convert all open-coded ->ack manipulations to use async_tx_ack
   and async_tx_test_ack.
2/ set the ack bit at prep time where possible
3/ make drivers store the flags at prep time
4/ add flags to the device_prep_dma_interrupt prototype

Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-04-17 13:25:54 -07:00
Dan Williams ce4d65a5db async_tx: kill ->device_dependency_added
DMA drivers no longer need to be notified of dependency submission
events as async_tx_run_dependencies and async_tx_channel_switch will
handle the scheduling and execution of dependent operations.

[sfr@canb.auug.org.au: extend this for fsldma]
Acked-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-04-17 13:25:54 -07:00