Commit Graph

73 Commits

Author SHA1 Message Date
Ira W. Snyder
8faa7cf828 dt/fsldma: fix build warning caused by of_platform_device changes
Commit 000061245a, "dt/powerpc:
Eliminate users of of_platform_{,un}register_driver" forgot to convert
the type of structure passed into platform_device_register() when it
was converted from of_platform_device_register. Fix it.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-04-10 23:34:38 -07:00
Linus Torvalds
6447f55da9 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (66 commits)
  avr32: at32ap700x: fix typo in DMA master configuration
  dmaengine/dmatest: Pass timeout via module params
  dma: let IMX_DMA depend on IMX_HAVE_DMA_V1 instead of an explicit list of SoCs
  fsldma: make halt behave nicely on all supported controllers
  fsldma: reduce locking during descriptor cleanup
  fsldma: support async_tx dependencies and automatic unmapping
  fsldma: fix controller lockups
  fsldma: minor codingstyle and consistency fixes
  fsldma: improve link descriptor debugging
  fsldma: use channel name in printk output
  fsldma: move related helper functions near each other
  dmatest: fix automatic buffer unmap type
  drivers, pch_dma: Fix warning when CONFIG_PM=n.
  dmaengine/dw_dmac fix: use readl & writel instead of __raw_readl & __raw_writel
  avr32: at32ap700x: Specify DMA Flow Controller, Src and Dst msize
  dw_dmac: Setting Default Burst length for transfers as 16.
  dw_dmac: Allow src/dst msize & flow controller to be configured at runtime
  dw_dmac: Changing type of src_master and dest_master to u8.
  dw_dmac: Pass Channel Priority from platform_data
  dw_dmac: Pass Channel Allocation Order from platform_data
  ...
2011-03-22 17:53:13 -07:00
Ira Snyder
a00ae34ac8 fsldma: make halt behave nicely on all supported controllers
The original dma_halt() function set the CA (channel abort) bit on both
the 83xx and 85xx controllers. This is incorrect on the 83xx, where this
bit means TEM (transfer error mask) instead. The 83xx doesn't support
channel abort, so we only do this operation on 85xx.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-03-11 17:52:37 -08:00
Ira Snyder
dc8d409157 fsldma: reduce locking during descriptor cleanup
This merges the fsl_chan_ld_cleanup() function into the dma_do_tasklet()
function to reduce locking overhead. In the best case, we will be able
to keep the DMA controller busy while we are freeing used descriptors.
In all cases, the spinlock is grabbed two times fewer than before on
each transaction.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-03-11 17:52:37 -08:00
Ira Snyder
9c4d1e7bde fsldma: support async_tx dependencies and automatic unmapping
Previous to this patch, the dma_run_dependencies() function has been
called while holding desc_lock. This function can call tx_submit() for
other descriptors, which may try to re-grab the lock. Avoid this by
moving the descriptors to be cleaned up to a temporary list, and
dropping the lock before cleanup.

At the same time, add support for automatic unmapping of src and dst
buffers, as offered by the DMAEngine API.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-03-11 17:52:37 -08:00
Ira Snyder
f04cd40701 fsldma: fix controller lockups
Enabling poisoning in the dmapool API quickly showed that the DMA
controller was fetching descriptors that should not have been in use.
This has caused intermittent controller lockups during testing.

I have been unable to figure out the exact set of conditions which cause
this to happen. However, I believe it is related to the driver using the
hardware registers to track whether the controller is busy or not. The
code can incorrectly decide that the hardware is idle due to lag between
register writes and the hardware actually becoming busy.

To fix this, the driver has been reworked to explicitly track the state
of the hardware, rather than try to guess what it is doing based on the
register values.

This has passed dmatest with 10 threads per channel, 100000 iterations
per thread several times without error. Previously, this would fail
within a few seconds.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-03-11 17:52:36 -08:00
Ira Snyder
31f4306c83 fsldma: minor codingstyle and consistency fixes
This fixes some minor violations of the coding style. It also changes
the style of the device_prep_dma_*() function definitions so they are
identical.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-03-11 17:52:36 -08:00
Ira Snyder
0ab09c3681 fsldma: improve link descriptor debugging
This adds better tracking to link descriptor allocations, callbacks, and
frees. This makes it much easier to track errors with link descriptors.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-03-11 17:52:36 -08:00
Ira Snyder
b158471ef6 fsldma: use channel name in printk output
This makes debugging the driver much easier when multiple channels are
running concurrently. In addition, you can see how much descriptor
memory each channel has allocated via the dmapool API in sysfs.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-03-11 17:52:36 -08:00
Ira Snyder
e8bd84df27 fsldma: move related helper functions near each other
This is a purely cosmetic cleanup. It is nice to have related functions
right next to each other in the code.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-03-11 17:52:36 -08:00
Grant Likely
000061245a dt/powerpc: Eliminate users of of_platform_{,un}register_driver
Get rid of old users of of_platform_driver in arch/powerpc.  Most
of_platform_driver users can be converted to use the platform_bus
directly.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-02-28 01:36:39 -07:00
Linus Torvalds
e1288cd72f Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (63 commits)
  ARM: PL08x: cleanup comments
  Update CONFIG_MD_RAID6_PQ to CONFIG_RAID6_PQ in drivers/dma/iop-adma.c
  ARM: PL08x: fix a warning
  Fix dmaengine_submit() return type
  dmaengine: at_hdmac: fix race while monitoring channel status
  dmaengine: at_hdmac: flags located in first descriptor
  dmaengine: at_hdmac: use subsys_initcall instead of module_init
  dmaengine: at_hdmac: no need set ACK in new descriptor
  dmaengine: at_hdmac: trivial add precision to unmapping comment
  dmaengine: at_hdmac: use dma_address to program DMA hardware
  pch_dma: support new device ML7213 IOH
  ARM: PL08x: prevent dma_set_runtime_config() reconfiguring memcpy channels
  ARM: PL08x: allow dma_set_runtime_config() to return errors
  ARM: PL08x: fix locking between prepare function and submit function
  ARM: PL08x: introduce 'phychan_hold' to hold on to physical channels
  ARM: PL08x: put txd's on the pending list in pl08x_tx_submit()
  ARM: PL08x: rename 'desc_list' as 'pend_list'
  ARM: PL08x: implement unmapping of memcpy buffers
  ARM: PL08x: store prep_* flags in async_tx structure
  ARM: PL08x: shrink srcbus/dstbus in txd structure
  ...
2011-01-17 10:54:41 -08:00
Forrest Shi
f3c677b997 fsldma: fix issue of slow dma
Fixed fsl dma slow issue by initializing dma mode register with
bandwidth control. It boosts dma performance and should works
with 85xx board.

Signed-off-by: Forrest Shi <b29237@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-12-13 14:05:27 -08:00
Li Yang
e2c8e425ba fsldma: add support to 36-bit physical address
Expand the dma_mask of fsldma device to 36-bit, indicating that the
DMA engine can deal with 36-bit physical address and does not need
the SWIOTLB to create bounce buffer for it when doing dma_map_*().

Signed-off-by: Li Yang <leoli@freescale.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-12-03 14:02:45 -08:00
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