Commit Graph

112 Commits

Author SHA1 Message Date
Russell King
409ec8db46 dmaengine: PL08x: move the bus and increment selection to dma prepare function
Move the bus and transfer increment selection to the DMA prepare
function rather than the slave configuration function.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:45 +01:00
Russell King
95442b2234 dmaengine: PL08x: get rid of device_fc in struct pl08x_dma_chan
As we now store the dma_slave_config in pl08x_dma_chan, we don't need
to store this separately.  Use the one in dma_slave_config directly.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:43 +01:00
Russell King
ed91c13d29 dmaengine: PL08x: get src/dst addr direct from dma_slave_config struct
Add a dma_slave_config struct to struct pl08x_dma_chan, and move the
src_addr/dst_addr arguments into this struct.  This is a step away
from using the dma_slave_config's direction member.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:42 +01:00
Russell King
550ec36f50 dmaengine: PL08x: constify channel names and bus_id strings
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:41 +01:00
Russell King
b23f204c8d dmaengine: PL08x: move private data structures into amba-pl08x.c
Move the driver private data structures into the driver itself, rather
than having them exposed to everyone in a header file.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:40 +01:00
Russell King
aeea1808fe dmaengine: PL08x: clean up get_signal/put_signal
Try to avoid dereferencing the DMA engine's channel struct in these
platform helpers; instead, pass a pointer to the channel data into
get_signal(), and the returned signal number to put_signal().

Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:38 +01:00
Russell King
48afb3112e dmaengine: PL08x: remove circular_buffer boolean from channel data
Circular buffers are not handled in this way; we have a separate API
call now to setup circular buffers.  So lets not mislead people with
this bool.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:37 +01:00
Russell King
c15a6ef6ea dmaengine: PL08x: remove redundant spinlock
The pl08x_driver_data spinlock is only ever initialized.  Nothing else
uses it.  Let's get rid of it.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:36 +01:00
Russell King
92d2fd619d dmaengine: PL08x: fix missed dma_transfer_direction fixup
db8196df4 (dmaengine: move drivers to dma_transfer_direction) missed
fixing up the "DMA_NONE" case.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:35 +01:00
Russell King
b843441a4c dmaengine: PL08x: remove runtime PM support
The runtime PM support conflicts with the generic AMBA bus PM, and also
causes a potential deadlock with the PL011 driver as it results in
interrupts being enabled beneath a spinlock.

I don't presently see any solution to this other than by removing the
runtime PM support entirely from the DMA engine driver.  Alternative
suggestions welcome.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-01 14:15:34 +01:00
Lars-Peter Clausen
fdaf9c4b22 dmaengine: Use dma_sg_len(sg) instead of sg->length
sg->length may or may not contain the length of the dma region to transfer,
depending on the architecture - dma_sg_len(sg) always will though. For the
architectures which use the drivers modified by this patch it probably is the
case that sg->length contains the dma transfer length. But to be consistent and
future proof change them to use dma_sg_len.

To quote Russel King:
	sg->length is meaningless to something performing DMA.

	In cases where sg_dma_len(sg) and sg->length are the same storage, then
	there's no problem. But scatterlists _can_ (and one some architectures) do
	split them - especially when you have an IOMMU which can allow you to
	combine a scatterlist into fewer entries.

	So, anything using sg->length for the size of a scatterlist's DMA transfer
	_after_ a call to dma_map_sg() is almost certainly buggy.

The patch has been generated using the following coccinelle patch:
<smpl>
@@
struct scatterlist *sg;
expression X;
@@
-sg[X].length
+sg_dma_len(&sg[X])
@@
struct scatterlist *sg;
@@
-sg->length
+sg_dma_len(sg)
</smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-05-11 12:04:38 +05:30
Lars-Peter Clausen
cbb796ccd8 dmaengine: Use sg_dma_address instead of sg_phys
dmaengine drivers should always use sg_dma_address instead of sg_phys to get the
addresses for the transfer from a sg element.

To quote Russel King:
	sg_phys(sg) of course has nothing to do with DMA addresses. It's the
	physical address _to the CPU_ of the memory associated with the scatterlist
	entry. That may, or may not have the same value for the DMA engine,
	particularly if IOMMUs are involved.

	And if these drivers are used on ARM, they must be fixed, sooner rather
	than later.  There's patches in the works which will mean we will end up
	with IOMMU support in the DMA mapping later, which means everything I've
	said above will become reality.

The patch has been generated using the following coccinelle patch:
<smpl>
@@
struct scatterlist *sg;
@@
-sg_phys(sg)
+sg_dma_address(sg)
</smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-05-11 12:04:38 +05:30
Vinod Koul
56cbb3dd48 Merge branch 'fixes' into next 2012-04-25 15:28:54 +05:30
Linus Walleij
affa115ed3 dma/amba-pl08x: add support for the Nomadik variant
The Nomadik PL080 variant has some extra protection bits that
may be set, so we need to check these bits to see if the
channels are actually available for the DMAengine to use.

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Alim Akhtar <alim.akhtar@gmail.com>
Cc: Alessandro Rubini <rubini@gnudd.com>
Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-04-25 15:21:47 +05:30
Davide Ciminaghi
88c08a3fba dmaengine/amba-pl08x : reset phychan_hold on terminate all
When a client calls pl08x_control with DMA_TERMINATE_ALL, it is correct
to terminate and release the phy channel currently in use (if one is in use),
but the phychan_hold counter must also be reset (otherwise it could get
trapped in an unbalanced state).

Signed-off-by: Davide Ciminaghi <ciminaghi@gnudd.com>
Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-04-25 15:10:57 +05:30
Linus Walleij
d29bf01941 dma/amba-pl08x: check for terminal count status only
For some reason I can't figure out we're reading the PL080_INT_STATUS
register instead of PL080_TC_STATUS when checking for the terminal
count. The PL080_INT_STATUS is a logical OR between the error and
terminal count status register and may not report what we want it
to, especially if there is an error and a terminal count at the same
time and the former is not lowered in time for the check in the TC
register. Make sure we read what we're actually interested in.

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Viresh Kumar <viresh.kumar@st.com>
Cc: Alim Akhtar <alim.akhtar@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-04-23 18:23:55 +05:30
Alexandre Bounine
185ecb5f4f dmaengine: add context parameter to prep_slave_sg and prep_dma_cyclic
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: Alexandre Bounine <alexandre.bounine@idt.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-03-21 19:20:23 +05:30
Russell King - ARM Linux
d3ee98cdcd dmaengine: consolidate initialization of cookies
Provide a common function to initialize a channels cookie values.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-03-13 11:37:22 +05:30
Russell King - ARM Linux
96a2af41c7 dmaengine: consolidate tx_status functions
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: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-03-13 11:37:14 +05:30
Russell King - ARM Linux
f7fbce07c6 dmaengine: provide a common function for completing a dma descriptor
Provide a common function to do the cookie mechanics for completing
a DMA descriptor.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-03-13 11:37:01 +05:30
Russell King - ARM Linux
884485e1f1 dmaengine: consolidate assignment of DMA cookies
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: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-03-13 11:36:52 +05:30
Russell King - ARM Linux
d2ebfb335b dmaengine: add private header file
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: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-03-13 11:36:44 +05:30
Russell King - ARM Linux
4d4e58de32 dmaengine: move last completed cookie into generic dma_chan structure
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: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-03-13 11:36:06 +05:30
Viresh Kumar
8c9f7aa316 dmaengine/amba-pl08x: Take flow controller info from DMA_SLAVE_CONFIG
Flow controller information is passed now from DMA_SLAVE_CONFIG option. This
patch makes changes in pl08x driver to use device_fc from it instead of platform
data.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-02-22 18:15:37 +05:30
Julia Lawall
880db3ff17 drivers/dma/amba-pl08x.c: adjust double test
Rewrite a duplicated test to test the correct value

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

// <smpl>
@@
expression E;
@@

(
* E
  || ... || E
|
* E
  && ... && E
)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-01-31 08:55:08 +05:30
Linus Torvalds
57f2685c16 Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma
* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (53 commits)
  ARM: mach-shmobile: specify CHCLR registers on SH7372
  dma: shdma: fix runtime PM: clear channel buffers on reset
  dma/imx-sdma: save irq flags when use spin_lock in sdma_tx_submit
  dmaengine/ste_dma40: clear LNK on channel startup
  dmaengine: intel_mid_dma: remove legacy pm interface
  ASoC: mxs: correct 'direction' of device_prep_dma_cyclic
  dmaengine: intel_mid_dma: error path fix
  dmaengine: intel_mid_dma: locking and freeing fixes
  mtd: gpmi-nand: move to dma_transfer_direction
  mtd: fix compile error for gpmi-nand
  mmc: mxs-mmc: fix the dma_transfer_direction migration
  dmaengine: add DMA_TRANS_NONE to dma_transfer_direction
  dma: mxs-dma: Don't use CLKGATE bits in CTRL0 to disable DMA channels
  dma: mxs-dma: make mxs_dma_prep_slave_sg() multi user safe
  dma: mxs-dma: Always leave mxs_dma_init() with the clock disabled.
  dma: mxs-dma: fix a typo in comment
  DMA: PL330: Remove pm_runtime_xxx calls from pl330 probe/remove
  video i.MX IPU: Fix display connections
  i.MX IPU DMA: Fix wrong burstsize settings
  dmaengine/ste_dma40: allow fixed physical channel
  ...

Fix up conflicts in drivers/dma/{Kconfig,mxs-dma.c,pl330.c}

The conflicts looked pretty trivial, but I'll ask people to verify them.
2012-01-17 18:40:24 -08:00
Viresh Kumar
8f0d30f9ee dmaengine/amba-pl08x: Config ccfg and increment phychan_hold if phychan is true
Currently, if plchan->phychan is true, we return immediately from
prep_phy_chan(). We must configure txd->ccfg and increment phychan_hold before
returning. Otherwise, request line number wouldn't be configured in this txd.

Reported-by: Rajeev Kumar <rajeev-dlh.kumar@st.com>
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2011-12-05 08:36:01 +05:30
Dave Martin
037566df2a dmaengine: pl08x: Enable module alias autogeneration for AMBA drivers
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
2011-11-22 10:58:30 +00:00
Vinod Koul
db8196df4b dmaengine: move drivers to dma_transfer_direction
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: Mika Westerberg <mika.westerberg@iki.fi>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2011-10-27 20:53:43 +05:30
Viresh Kumar
c12056466d dmaengine/amba-pl08x: Check txd->llis_va before freeing dma_pool
In pl08x_free_txd(), check if pool is allocated successfully before freeing it.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-09-19 15:13:16 +05:30
Viresh Kumar
b7f69d9d42 dmaengine/amba-pl08x: Add support for sg len greater than one for slave transfers
Untill now, sg_len greater than one is not supported. This patch adds support to
do that.

Note: Still, if peripheral is flow controller, sg_len can't be greater that one.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-09-19 15:13:06 +05:30
Russell King - ARM Linux
7703eac96a dmaengine: amba-pl08x: make filter check that the channel is owned by pl08x
Before converting the dma channel to our private data structure, first
check that the channel is indeed one which our driver registered.  We
do this by ensuring that the underlying device is bound to our driver.

This avoids potential oopses if we try to reference 'plchan->name'
against a foreign drivers dma channel.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-09-05 18:57:38 +05:30
Vinod Koul
8516f52fa4 Merge branch 'next' into v3.1-rc4
Fixed trivial conflicts  in  drivers/dma/amba-pl08x.c

Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-09-02 16:43:44 +05:30
Viresh Kumar
57001a606f dmaengine/amba-pl08x: Call pl08x_free_txd() instead of calling kfree() directly
pl08x_prep_channel_resources() is calling kfree() directly for txd(). To
maintain consistency in code call pl08x_free_txd() instead.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:35:07 +05:30
Viresh Kumar
0a2356572b dmaengine/amba-pl08x: Pass flow controller information with slave channel data
At least, on SPEAr platforms there is one peripheral, JPEG, which can be flow
controller for DMA transfer. Currently DMA controller driver didn't support
peripheral flow controller configurations.

This patch adds device_fc field in struct pl08x_channel_data, which will be used
only for slave transfers and is not used in case of mem2mem transfers.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:39 +05:30
Viresh Kumar
036f05fd6d dmaengine/amba-pl08x: Choose peripheral bus as master bus
When we have DMA transfers between peripheral and memory, then we shouldn't
reduce width of peripheral at all, as that may be a strict requirement. But we
can always reduce width of memory access, with some compromise in performance.
Thus, we must select peripheral as master and not memory.

Also this rearranges code to make it shorter.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:39 +05:30
Viresh Kumar
e071916580 dmaengine/amba-pl08x: Align lli_len to max(src.width, dst.width)
Currently lli_len is aligned to min of two widths, which looks to be incorrect.
Instead it should be aligned to max of both widths.

Lets say, total_size = 441 bytes

MIN: lets check if min() suits or not:

CASE 1: srcwidth = 1, dstwidth = 4
min(src, dst) = 1

i.e. We program transfer size in control reg to 441.
Now, till 440 bytes everything is fine, but on the last byte DMAC can't transfer
1 byte to dst, as its width is 4.

CASE 2: srcwidth = 4, dstwidth = 1
min(src, dst) = 1

i.e. we program transfer size in control reg to 110 (data transferred = 110 * srcwidth).
So, here too 1 byte is left, but on the source side.

MAX: Lets check if max() suits or not:

CASE 3: srcwidth = 1, dstwidth = 4
max(src, dst) = 4

Aligned size is 440

i.e. We program transfer size in control reg to 440.
Now, all 440 bytes will be transferred without any issues.

CASE 4: srcwidth = 4, dstwidth = 1
max(src, dst) = 4

Aligned size is 440

i.e. We program transfer size in control reg to 110 (data transferred = 110 * srcwidth).
Now, also all 440 bytes will be transferred without any issues.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:39 +05:30
Viresh Kumar
03af500f74 dmaengine/amba-pl08x: Add prep_single_byte_llis() routine
Code for creating single byte llis is present at several places. Create a
routine to avoid code redundancy.

Also, we don't need one lli per single byte transfer, we can have single lli to
do all single byte transfer.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:39 +05:30
Viresh Kumar
fa6a940bf1 dmaengine/amba-pl08x: max_bytes_per_lli is TRANSFER_SIZE * src_width (not MIN(width))
max_bytes_per_lli = bd.srcbus.buswidth * PL080_CONTROL_TRANSFER_SIZE_MASK;
This is confirmed by ARM support guys.

Below is summary of mail exchange with them:

[Viresh] What is the total data to be transferred in case source and destination
bus widths are different. Suppose, source bus width is 2 bytes and destination
is 4 bytes. Now in order to transfer 80 bytes, what should be value of
TransferSize field in control reg: 40? or 20?.

[David from ARM] The value that is programmed into the TransferSize field should
be the number of <SourceWidth> transfers needed to achieve the required data
transfer.

So, to transfer 80 bytes, with a Source Width of 2, the TransferSize field =
should be programmed with:

        Total transfer size
        ------------------- = 40
          <source width>

[Viresh] Will this change if source is 4 bytes and dest is 2?

[David] Yes - the calculation then becomes:

        Total transfer size
        ------------------- =20
          <source width>

Also, max_bytes_per_lli must be calculated after fixing src and dest widths not
before that. So move this code to the correct place.

This patch also removes max_bytes_per_lli from earlier print message, as till
that point max_bytes_per_lli is unknown.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:39 +05:30
Viresh Kumar
16a2e7d359 dmaengine/amba-pl08x: Get rid of pl08x_pre_boundary()
Pl080 Manual says: "Bursts do not cross the 1KB address boundary"

We can program the controller to cross 1 KB boundary on a burst and controller
can take care of this boundary condition by itself.

Following is the discussion with ARM Technical Support Guys (David):
[Viresh] Manual says: "Bursts do not cross the 1KB address boundary"

What does that actually mean? As, Maximum size transferable with a single LLI is
4095 * 4 =16380 ~ 16KB. So, if we don't have src/dest address aligned to burst
size, we can't use this big of an LLI.

[David] There is a difference between bursts describing the total data
transferred by the DMA controller and AHB bursts. Bursts described by the
programmable parameters in the PL080 have no direct connection with the bursts
that are seen on the AHB bus.

The statement that "Bursts do not cross the 1KB address boundary" in the TRM is
referring to AHB bursts, where this limitation is a requirement of the AHB spec.
You can still issue bursts within the PL080 that are in excess of 1KB. The
PL080 will make sure that its bursts are broken down into legal AHB bursts which
will be formatted to ensure that no AHB burst crosses a 1KB boundary.

Based on above discussion, this patch removes all code related to 1 KB boundary
as we are not required to handle this in driver.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:38 +05:30
Viresh Kumar
28da28365d dmaengine/amba-pl08x: Schedule tasklet in case of error interrupt
Currently, if error interrupt occurs, nothing is done in interrupt handler (just
clearing the interrupts). We must somehow indicate this to the user that DMA is
over, due to ERR interrupt or TC interrupt.

So, this patch just schedules existing tasklet, with a print showing error
interrupt has occurred on which channels.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:38 +05:30
Viresh Kumar
16ca810504 dmaengine/amba-pl08x: No need to check "ch->signal < 0"
We have just executed following in pl08x_get_phy_channel():
	ch->signal = -1;

We don't have to compare "ch->signal < 0", as this will always be true.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:38 +05:30
Viresh Kumar
48a59ef357 dmaengine/amba-pl08x: Simplify pl08x_ensure_on()
Simply writing 1 on bit 0 is sufficient instead of reading and clearing bits.
Also as per manual, for bit 3-31 of DMACConfiguration register:
"read undefined, write as 0"

So, we must not rely on values read from this registers bit 3-31.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:38 +05:30
Viresh Kumar
b7b6018bad dmaengine/amba-pl08x: support runtime PM
Insert notifiers for the runtime PM API. With this the runtime PM layer kicks in
to action where used.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:38 +05:30
Viresh Kumar
175a5e617c dmaengine/amba-pl08x: Changing few prints to dev_dbg from dev_info
For 8 memory and 16 slave channels 35 boot print lines are printed. And that is
too much. Most of this would be more useful for debugging. So moving few of them
to dev_dbg instead of dev_info. Now only 3 prints will be printed.

This also rearrange one of the debug message to fit into two lines.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:38 +05:30
Viresh Kumar
0532e6fced dmaengine/amba-pl08x: Remove redundant comment and rewrite original
Similar comment is present over routine also pl08x_choose_master_bus(). Keeping
one of them. Also rewrite that comment to convey message clearly.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:38 +05:30
Viresh Kumar
b201c111c8 dmaengine/amba-pl08x: pass (*ptr) to sizeof() instead of (struct xyz)
As mentioned in Documentation/CodingStyle,

The preferred form for passing a size of a struct is the following:
   p = kmalloc(sizeof(*p), ...);

The alternative form where struct name is spelled out hurts readability and
introduces an opportunity for a bug when the pointer variable type is changed
but the corresponding sizeof that is passed to a memory allocator is not.

This patch replaces (struct xyz) with *ptr at several occurrences in driver.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:37 +05:30
Viresh Kumar
0c38d70139 dmaengine/amba-pl08x: Rearrange inclusion of header files in ascending order
Header files included in driver are not present in alphabetical order. Rearrange
them in alphabetical order.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:37 +05:30
Viresh Kumar
3e27ee8448 dmaengine/amba-pl08x: Resolve formatting issues
There were few formatting related issues in code. This patch fixes them.
Fixes include:
- Remove extra blank lines
- align code to 80 cols
- combine several lines to one line

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-25 19:33:37 +05:30
Russell King
4d66164e99 dmaengine: PL08x: Fix trivial build error
Something changed during the 3.1 merge window in the include files
which now causes the pl08x DMA engine driver to fail to build.  Fix
this by adding the now necessary dma-mapping.h include:

drivers/dma/amba-pl08x.c: In function ■pl08x_unmap_buffers■:
drivers/dma/amba-pl08x.c:1524: error: implicit declaration of function ■dma_unmap_single■
drivers/dma/amba-pl08x.c:1527: error: implicit declaration of function ■dma_unmap_page■

Acked-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-08-09 08:42:28 +01:00