Commit Graph

12 Commits

Author SHA1 Message Date
Joel Fernandes
c5f47990aa dma: edma: Find missed events and issue them
In an effort to move to using Scatter gather lists of any size with
EDMA as discussed at [1] instead of placing limitations on the driver,
we work through the limitations of the EDMAC hardware to find missed
events and issue them.

The sequence of events that require this are:

For the scenario where MAX slots for an EDMA channel is 3:

SG1 -> SG2 -> SG3 -> SG4 -> SG5 -> SG6 -> Null

The above SG list will have to be DMA'd in 2 sets:

(1) SG1 -> SG2 -> SG3 -> Null
(2) SG4 -> SG5 -> SG6 -> Null

After (1) is succesfully transferred, the events from the MMC controller
donot stop coming and are missed by the time we have setup the transfer
for (2). So here, we catch the events missed as an error condition and
issue them manually.

In the second part of the patch, we make handle the NULL slot cases:
For crypto IP, we continue to receive events even continuously in
NULL slot, the setup of the next set of SG elements happens after
the error handler executes. This is results in some recursion problems.
Due to this, we continously receive error interrupts when we manually
trigger an event from the error handler.

We fix this, by first detecting if the Channel is currently transferring
from a NULL slot or not, that's where the edma_read_slot in the error
callback from interrupt handler comes in. With this we can determine if
the set up of the next SG list has completed, and we manually trigger
only in this case. If the setup has _not_ completed, we are still in NULL
so we just set a missed flag and allow the manual triggerring to happen
in edma_execute which will be eventually called. This fixes the above
mentioned race conditions seen with the crypto drivers.

[1] http://marc.info/?l=linux-omap&m=137416733628831&w=2

Signed-off-by: Joel Fernandes <joelf@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-09-04 18:38:46 +05:30
Joel Fernandes
534070622d dma: edma: Write out and handle MAX_NR_SG at a given time
Process SG-elements in batches of MAX_NR_SG if they are greater
than MAX_NR_SG. Due to this, at any given time only those many
slots will be used in the given channel no matter how long the
scatter list is. We keep track of how much has been written
inorder to process the next batch of elements in the scatter-list
and detect completion.

For such intermediate transfer completions (one batch of MAX_NR_SG),
make use of pause and resume functions instead of start and stop
when such intermediate transfer is in progress or completed as we
donot want to clear any pending events.

Signed-off-by: Joel Fernandes <joelf@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-09-04 18:38:46 +05:30
Joel Fernandes
6fbe24da82 dma: edma: Setup parameters to DMA MAX_NR_SG at a time
Changes are made here for configuring existing parameters to support
DMA'ing them out in batches as needed.

Also allocate as many as slots as needed by the SG list, but not more
than MAX_NR_SG. Then these slots will be reused accordingly.
For ex, if MAX_NR_SG=10, and number of SG entries is 40, still only
10 slots will be allocated to DMA the entire SG list of size 40.

Also enable TC interrupts for slots that are a last in a current
iteration, or that fall on a MAX_NR_SG boundary.

Signed-off-by: Joel Fernandes <joelf@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-09-04 18:38:46 +05:30
Andy Shevchenko
43e33e484e edma: no need to assign residue to 0 explicitly
Residue value is assigned to 0 by dma_cookie_status().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-05 09:32:24 +05:30
Matt Porter
3ad7a42d5a ARM: davinci: move private EDMA API to arm/common
Move mach-davinci/dma.c to common/edma.c so it can be used
by OMAP (specifically AM33xx) as well.

Signed-off-by: Matt Porter <mporter@ti.com>
Acked-by: Chris Ball <cjb@laptop.org> # davinci_mmc.c
Acked-by: Mark Brown <broonie@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
[nsekhar@ti.com: dropped davinci sffsdr changes]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
2013-06-18 10:52:03 +05:30
Linus Torvalds
5115f3c19d Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma
Pull slave-dmaengine updates from Vinod Koul:
 "This is fairly big pull by my standards as I had missed last merge
  window.  So we have the support for device tree for slave-dmaengine,
  large updates to dw_dmac driver from Andy for reusing on different
  architectures.  Along with this we have fixes on bunch of the drivers"

Fix up trivial conflicts, usually due to #include line movement next to
each other.

* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (111 commits)
  Revert "ARM: SPEAr13xx: Pass DW DMAC platform data from DT"
  ARM: dts: pl330: Add #dma-cells for generic dma binding support
  DMA: PL330: Register the DMA controller with the generic DMA helpers
  DMA: PL330: Add xlate function
  DMA: PL330: Add new pl330 filter for DT case.
  dma: tegra20-apb-dma: remove unnecessary assignment
  edma: do not waste memory for dma_mask
  dma: coh901318: set residue only if dma is in progress
  dma: coh901318: avoid unbalanced locking
  dmaengine.h: remove redundant else keyword
  dma: of-dma: protect list write operation by spin_lock
  dmaengine: ste_dma40: do not remove descriptors for cyclic transfers
  dma: of-dma.c: fix memory leakage
  dw_dmac: apply default dma_mask if needed
  dmaengine: ioat - fix spare sparse complain
  dmaengine: move drivers/of/dma.c -> drivers/dma/of-dma.c
  ioatdma: fix race between updating ioat->head and IOAT_COMPLETION_PENDING
  dw_dmac: add support for Lynxpoint DMA controllers
  dw_dmac: return proper residue value
  dw_dmac: fill individual length of descriptor
  ...
2013-02-26 09:24:48 -08:00
Andy Shevchenko
373459eee0 edma: do not waste memory for dma_mask
Accordingly to commentary in the platform_device_register_full the memory
allocated for dma_mask will not going to be freed. That's why is better to
assign dma_mask afterwards.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-02-14 20:00:53 +05:30
Matt Porter
661f7cb55c dma: edma: fix slave config dependency on direction
The edma_slave_config() implementation depends on the
direction field such that it will not properly configure
a slave channel when called without direction set.

This fixes the implementation so that the slave config
is copied as is and prep_slave_sg() handles the
direction dependent handling. spi-omap2-mcspi and
omap_hsmmc both expose this bug as they configure the
slave channel config from a common path with an unconfigured
direction field.

Signed-off-by: Matt Porter <mporter@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-01-20 04:04:29 -08:00
Greg Kroah-Hartman
4bf27b8b33 Drivers: dma: remove __dev* attributes.
CONFIG_HOTPLUG is going away as an option.  As a result, the __dev*
markings need to be removed.

This change removes the use of __devinit, __devexit_p, __devinitconst,
and __devexit from these drivers.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Viresh Kumar <viresh.linux@gmail.com>
Cc: Dan Williams <djbw@fb.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Barry Song <baohua.song@csr.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Jassi Brar <jassisinghbrar@gmail.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-03 15:57:15 -08:00
Bill Pemberton
463a1f8b3c dma: remove use of __devinit
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.

Signed-off-by: Bill 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: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:42:36 -08:00
Bill Pemberton
a7d6e3ec28 dma: remove use of __devexit_p
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Barry Song <baohua.song@csr.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:41:36 -08:00
Matt Porter
c2dde5f8f2 dmaengine: add TI EDMA DMA engine driver
Add a DMA engine driver for the TI EDMA controller. This driver
is implemented as a wrapper around the existing DaVinci private
DMA implementation. This approach allows for incremental conversion
of each peripheral driver to the DMA engine API. The EDMA driver
supports slave transfers but does not yet support cyclic transfers.

Signed-off-by: Matt Porter <mporter@ti.com>
Tested-by: Tom Rini <trini@ti.com>
Tested-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-09-01 06:14:02 +05:30