Move the DMA request muxing into the slave prepare code and txd
release/completion code. This means we only hold the DMA request
mux while there are descriptors waiting to be started or are in
progress.
This leaves txd->direction as a write-only variable; remove 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>
Convert PL08x to use a list of completed descriptors rather than
merely relying upon a single pointer. This makes it possible to
schedule the tasklet for other purposes, and makes our behaviour
similar to virt-dma.
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>
Keep track of the number of descriptors currently using a MUX setting
on a per-channel basis. This allows us to know when we have descriptors
queued somewhere which have been assigned a DMA request signal.
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>
Move the signal handling out of the physical channel structure into
the virtual channel structure, where it should belong as it has more
to do with the virtual channel than the physical one.
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>
Split the DMA request mux signal handling from the physical channel
allocation code. The physical channel has very little to do with the
DMA request input which will be used, so these should be two separate
operations.
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>
Get rid of the unnecessary checks in dma_slave_config utilizing
the DMA direction. This allows us to move the computation of
cctl to the prepare 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>
Ignore the direction argument in dma_slave_config, and configure both
directions independently. We still check that the configuration for
the intended direction is valid; this check will eventually be dropped.
This check is just for debugging at present.
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>
Extract the functionality from dma_slave_config to generate the cctl
values for a given bus width and burst size. This allows us to use
this elsewhere in the driver, namely the prepare functions.
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
