With this series, this check is no longer required and
we shouldn't need to reject drivers DMA'ing more than the
MAX number of slots.
Signed-off-by: Joel Fernandes <joelf@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Dummy slot has been used as a way for missed-events not to be
reported as missing. This has been particularly troublesome for cases
where we might want to temporarily pause all incoming events.
For EDMA DMAC, there is no way to do any such pausing of events as
the occurence of the "next" event is not software controlled.
Using "edma_pause" in IRQ handlers doesn't help as by then the event
in concern from the slave is already missed.
Linking a dummy slot, is seen to absorb these events which we didn't
want to miss. So we don't link to dummy, but instead leave it linked
to NULL set, allow an error condition and detect the channel that
missed it.
Consider the case where we have a scatter-list like:
SG1->SG2->SG3->SG4->SG5->SG6->Null
For ex, for a MAX_NR_SG of 2, earlier we were splitting this as:
SG1->SG2->Null
SG3->SG4->Null
SG5->SG6->Null
Now we split it as
SG1->SG2->Null
SG3->SG4->Null
SG5->SG6->Dummy
This approach results in lesser unwanted interrupts that occur
for the last list split. The Dummy slot has the property of not
raising an error condition if events are missed unlike the Null
slot. We are OK with this as we're done with processing the
whole list once we reach Dummy.
Signed-off-by: Joel Fernandes <joelf@ti.com>
[modifed duplicate s-o-b & patch title]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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>
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>
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>
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>
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>
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
...
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>
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>
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>
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>
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>
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>
Joel Fernandes