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: NMaxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

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: NMaxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

A platform_driver does not need to set an owner, it will be populated by the
driver core.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

since users have been move to fsl_dma_external_start() API, so remove this
now
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

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: NVinod Koul <vinod.koul@intel.com>

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: NHongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: NQiang Liu <qiang.liu@freescale.com>
Signed-off-by: NIra W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

This patch adds suspend and resume functions for Freescale DMA driver.
Signed-off-by: NHongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The usage of spin_lock_irqsave() is a stronger locking mechanism than is
required throughout the driver. The minimum locking required should be used
instead. Interrupts will be turned off and context will be saved, it is
unnecessary to use irqsave.

This patch changes all instances of spin_lock_irqsave() to spin_lock_bh(). All
manipulation of protected fields is done using tasklet context or weaker, which
makes spin_lock_bh() the correct choice.
Signed-off-by: NHongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: NQiang Liu <qiang.liu@freescale.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

These functions will be modified in the next patch in the series. By moving the
function in a patch separate from the changes, it will make review easier.
Signed-off-by: NHongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: NQiang Liu <qiang.liu@freescale.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

There are several places where descriptors are freed using identical code.
This patch puts this code into a function to reduce code duplication.
Signed-off-by: NHongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: NQiang Liu <qiang.liu@freescale.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Delete attribute DMA_INTERRUPT because fsldma doesn't support this function,
exception will be thrown if talitos is used to offload xor at the same time.
Signed-off-by: NHongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: NQiang Liu <qiang.liu@freescale.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Methods of accessing DMA controller registers are inconsistent, some registers
are accessed by DMA_IN/OUT directly, while others are accessed by functions
get/set_* which are wrappers of DMA_IN/OUT, and even for the BCR register, it
is read by get_bcr but written by DMA_OUT.
This patch unifies the inconsistent methods, all registers are accessed by
get/set_* now.
Signed-off-by: NHongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Some codes are calling chan_dbg with FSL_DMA_LD_DEBUG surrounded, it is really
unnecessary to use such a macro because chan_dbg is a wrapper of dev_dbg, we do
have corresponding DEBUG macro to switch on/off dev_dbg, and most of the other
codes are also calling chan_dbg directly without using FSL_DMA_LD_DEBUG.
Signed-off-by: NHongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

drivers/dma/fsldma.c: In function 'fsldma_cleanup_descriptor':
drivers/dma/fsldma.c:860:6: warning: unused variable 'len' [-Wunused-variable]
drivers/dma/fsldma.c:859:13: warning: unused variable 'dst' [-Wunused-variable]
drivers/dma/fsldma.c:858:13: warning: unused variable 'src' [-Wunused-variable]
drivers/dma/fsldma.c:857:17: warning: unused variable 'dev' [-Wunused-variable]
- due to unmap changes

drivers/dma/fsldma.c: In function 'fsl_dma_tx_submit':
drivers/dma/fsldma.c:428:2: warning: 'cookie' may be used uninitialized in this function [-Wuninitialized]
- long standing warning

Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Li Yang <leoli@freescale.com>
Cc: Zhang Wei <zw@zh-kernel.org>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Remove support for DMA unmapping from drivers as it is no longer
needed (DMA core code is now handling it).

Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
[djbw: fix up chan2parent() unused warning in drivers/dma/dw/core.c]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Add a hook for a common dma unmap implementation to enable removal of
the per driver custom unmap code.  (A reworked version of Bartlomiej
Zolnierkiewicz's patches to remove the custom callbacks and the size
increase of dma_async_tx_descriptor for drivers that don't care about
raid).

Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Dave Jiang <dave.jiang@intel.com>
[bzolnier: prepare pl330 driver for adding missing unmap while at it]
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

This patch adds support to 8-channel DMA engine, thus the driver works for both
the new 8-channel and the legacy 4-channel DMA engines.
Signed-off-by: NHongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Powerpc is a mess of implicit includes by prom.h. Add the necessary
explicit includes to drivers in preparation of prom.h cleanup.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NGrant Likely <grant.likely@linaro.org>

Accordingly to dma_cookie_status() description locking is not required.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Li Yang <leoli@freescale.com>
Cc: Zhang Wei <zw@zh-kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Use the wrapper functions for getting and setting the driver data using
platform_device instead of using dev_{get,set}_drvdata() with &pdev->dev,
so we can directly pass a struct platform_device.

Also, unnecessary dev_set_drvdata() is removed, because the driver core
clears the driver data to NULL after device_release or on probe failure.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Cc: Li Yang <leoli@freescale.com>
Cc: Zhang Wei <zw@zh-kernel.org>
Cc: Barry Song <baohua.song@csr.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Correct spelling typo in drivers/dma.
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Add context parameter to device_prep_slave_sg() and device_prep_dma_cyclic()
interfaces to allow passing client/target specific information associated
with the data transfer.
Modify all affected DMA engine drivers.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

Ensure all DMA engine drivers initialize their cookies in the same way,
so that they all behave in a similar fashion.  This means their first
issued cookie will be 2 rather than 1, and will increment to INT_MAX
before returning 1 and starting over.

In connection with this, Dan Williams said:
> Russell King wrote:
> > Secondly, some DMA engine drivers initialize the dma_chan cookie to 0,
> > others to 1.  Is there a reason for this, or are these all buggy?
>
> I know that ioat and iop-adma expect 0 to mean "I have cleaned up this
> descriptor and it is idle", and would break if zero was an in-flight
> cookie value.  The reserved usage of zero is an driver internal
> concern, but I have no problem formalizing it as a reserved value.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

Now that we have the completed cookie in the dma_chan structure, we
can consolidate the tx_status functions by providing a function to set
the txstate structure and returning the DMA status.  We also provide
a separate helper to set the residue for cookies which are still in
progress.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

Provide a common function to do the cookie mechanics for completing
a DMA descriptor.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

Everyone deals with assigning DMA cookies in the same way (it's part of
the API so they should be), so lets consolidate the common code into a
helper function to avoid this duplication.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

Add a local private header file to contain definitions and declarations
which should only be used by DMA engine drivers.

We also fix linux/dmaengine.h to use LINUX_DMAENGINE_H to guard against
multiple inclusion.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

Every DMA engine implementation declares a last completed dma cookie
in their private dma channel structures.  This is pointless, and
forces driver specific code.  Move this out into the common dma_chan
structure.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

fixup usage of dma direction by introducing dma_transfer_direction,
this patch moves dma/drivers/* to use new enum

Cc: Jassi Brar <jaswinder.singh@linaro.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Viresh Kumar <viresh.kumar@st.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Mika Westerberg <mika.westerberg@iki.fi>
Cc: H Hartley Sweeten <hartleys@visionengravers.com>
Cc: Li Yang <leoli@freescale.com>
Cc: Zhang Wei <zw@zh-kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Yong Wang <yong.y.wang@intel.com>
Cc: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com>
Cc: Boojin Kim <boojin.kim@samsung.com>
Cc: Barry Song <Baohua.Song@csr.com>
Acked-by: NMika Westerberg <mika.westerberg@iki.fi>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NViresh Kumar <viresh.kumar@st.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>

Commit 00006124, "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: NIra W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

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: NIra W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

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: NIra W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

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: NIra W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

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: NIra W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

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: NIra W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

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: NIra W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

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: NIra W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

This is a purely cosmetic cleanup. It is nice to have related functions
right next to each other in the code.
Signed-off-by: NIra W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

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: NGrant Likely <grant.likely@secretlab.ca>