The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Ludovic Desroches<ludovic.desroches@microchip.com>
Link: https://lore.kernel.org/r/20200507190038.GA15272@embeddedor
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Having a list of descriptors allocated for the channel at
device_alloc_chan_resources() time is a sign for bad free usage.
Return err and add a debug message in case the channel is not
free from a previous use.
atchan->descs_allocated becomes useless, get rid of it. More,
drop the error message in atc_desc_get() because now it would
introduce an extra if statement. The callers of atc_desc_get()
already print error messages in case the callee fails, no one
is hurt.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Link: https://lore.kernel.org/r/20200123140237.125799-3-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 3cab1e7112 ("lib/vsprintf: refactor duplicate code
to special_hex_number()") %pad doesn't need 0x prefix so drop that.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
dma_addr_t may be defined as 32 or 64 bit depending on configuration,
so it cannot be printed using the normal format strings, as
gcc correctly warns:
drivers/dma/at_hdmac.c: In function 'atc_prep_dma_interleaved':
drivers/dma/at_hdmac.c:731:28: warning: format '%x' expects argument of type 'unsigned int', but argument 4 has type 'dma_addr_t {aka long long unsigned int}' [-Wformat=]
This changes the format strings to use the special "%pad" format
string that prints a dma_addr_t, and changes the arguments so we
pass the address by reference as required.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The memset and scatter gathered memset are going to use some common logic
to create their descriptors.
Move that logic into a function of its own so that we can share it with the
future memset_sg callback.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This time we have aded a new capability for scatter-gathered memset using
dmaengine APIs. This is supported in xdmac & hdmac drivers
We have added support for reusing descriptors for examples like video
buffers etc. Driver will follow
The behaviour of descriptor ack has been clarified and documented
New devices added are:
- dma controller in sun[457]i SoCs
- lpc18xx dmamux
- ZTE ZX296702 dma controller
- Analog Devices AXI-DMAC DMA controller
- eDMA support for dma-crossbar
- imx6sx support in imx-sdma driver
- imx-sdma device to device support
Others
- jz4780 fixes
- ioatdma large refactor and cleanup for removal of ioat v1 and v2 which is
deprecated and fixes
- ACPI support in X-Gene DMA engine driver
- ipu irq fixes
- mvxor fixes
- minor fixes spread thru drivers
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQIcBAABAgAGBQJV5+nSAAoJEHwUBw8lI4NHiXQQAI/++7PmUGZ6BDZGu0B9Bj7U
JalNijm43p858nka1zVhDea8pi7Cq3zJdE8EAB7FPQGESvCODWr62oZBr+mSaQ1C
oU1RTIRTSiU2HPE4EFeGUvVGrnmTbHR2b1apI1SU41gKn+oQ5RJRRoQwEVwO6uuZ
1VYcUqhurIAZs1FrMIAUa2vg7KTcK9UotfwR2gGBmSvXMf1aJ/dNZC7i/pBJjoyt
v6KrLuYjEBAJvY7l368+NhLY/MS+2xdCMQo84B+HNEG7eA7y2MFOcRPXQA3a7dzr
NwNuAZcTYDU11r2jiAPcnBM5sPo4bokX6Td0oDbYH6Rn2uIWlof7jGIceUaWLQQq
QGZc4QPI4KdjTGNedRN8g9zqv0irFVfDr5v1A+B7N7ehvlubnB4jV8LmLpqN6UQH
B38VnDJ3hqdZ6j9RHQTyUoQskSYMPbOAUYbL0qQLkyx8AnLc8TRv7DgtSvZjnz5W
oF6So2A5SWZ7UmXKupd6TKtdyG3xtFAh+/MGVQ1RS9bCmnyhaIxJRiJwfftCBTBx
IZePOsqlwl2dojM62BDlGS4CLRZve2VgiUEJaPINsdm/On3tQs9+iDbNY3cpvLQS
P9u4po1TQPZnKG732vPAxEqdlq709kta7Fj5KIEvNjuWBBGKfypNP8BHKRvTLFlR
kcbO03NzwSO6PZpmiUsx
=gQZ6
-----END PGP SIGNATURE-----
Merge tag 'dmaengine-4.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine updates from Vinod Koul:
"This time we have aded a new capability for scatter-gathered memset
using dmaengine APIs. This is supported in xdmac & hdmac drivers
We have added support for reusing descriptors for examples like video
buffers etc. Driver will follow
The behaviour of descriptor ack has been clarified and documented
New devices added are:
- dma controller in sun[457]i SoCs
- lpc18xx dmamux
- ZTE ZX296702 dma controller
- Analog Devices AXI-DMAC DMA controller
- eDMA support for dma-crossbar
- imx6sx support in imx-sdma driver
- imx-sdma device to device support
Other:
- jz4780 fixes
- ioatdma large refactor and cleanup for removal of ioat v1 and v2
which is deprecated and fixes
- ACPI support in X-Gene DMA engine driver
- ipu irq fixes
- mvxor fixes
- minor fixes spread thru drivers"
[ The Kconfig and Makefile entries got re-sorted alphabetically, and I
handled the conflict with the new Intel integrated IDMA driver by
slightly mis-sorting it on purpose: "IDMA64" got sorted after "IMX" in
order to keep the Intel entries together. I think it might be a good
idea to just rename the IDMA64 config entry to INTEL_IDMA64 to make
the sorting be a true sort, not this mismash.
Also, this merge disables the COMPILE_TEST for the sun4i DMA
controller, because it does not compile cleanly at all. - Linus ]
* tag 'dmaengine-4.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (89 commits)
dmaengine: ioatdma: add Broadwell EP ioatdma PCI dev IDs
dmaengine :ipu: change ipu_irq_handler() to remove compile warning
dmaengine: ioatdma: Fix variable array length
dmaengine: ioatdma: fix sparse "error" with prep lock
dmaengine: hdmac: Add memset capabilities
dmaengine: sort the sh Makefile
dmaengine: sort the sh Kconfig
dmaengine: sort the dw Kconfig
dmaengine: sort the Kconfig
dmaengine: sort the makefile
drivers/dma: make mv_xor.c driver explicitly non-modular
dmaengine: Add support for the Analog Devices AXI-DMAC DMA controller
devicetree: Add bindings documentation for Analog Devices AXI-DMAC
dmaengine: xgene-dma: Fix the lock to allow client for further submission of requests
dmaengine: ioatdma: fix coccinelle warning
dmaengine: ioatdma: fix zero day warning on incompatible pointer type
dmaengine: tegra-apb: Simplify locking for device using global pause
dmaengine: tegra-apb: Remove unnecessary return statements and variables
dmaengine: tegra-apb: Avoid unnecessary channel base address calculation
dmaengine: tegra-apb: Remove unused variables
...
Just like for the XDMAC, the SoCs that embed the HDMAC don't have any kind
of GPU, and need to accelerate a few framebuffer-related operations through
their DMA controller.
However, unlike the XDMAC, the HDMAC doesn't have the memset capability
built-in. That can be easily emulated though, by doing a transfer with a
fixed address on the variable that holds the value we want to set.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
As claimed by the programmer datasheet and confirmed by the IP designer,
the Block Transfer Size (BTSIZE) bitfield of the Channel x Control A
Register (CTRLAx) always refers to a number of Source Width (SRC_WIDTH)
transfers.
Both the SRC_WIDTH and BTSIZE bitfields can be extacted from the CTRLAx
register to compute the DMA residue. So the 'tx_width' field is useless
and can be removed from the struct at_desc.
Before this patch, atc_prep_slave_sg() was not consistent: BTSIZE was
correctly initialized according to the SRC_WIDTH but 'tx_width' was always
set to reg_width, which was incorrect for MEM_TO_DEV transfers. It led to
bad DMA residue when 'tx_width' != SRC_WIDTH.
Also the 'tx_width' field was mostly set only in the first and last
descriptors. Depending on the kind of DMA transfer, this field remained
uninitialized for intermediate descriptors. The accurate DMA residue was
computed only when the currently processed descriptor was the first or the
last of the chain. This algorithm was a little bit odd. An accurate DMA
residue can always be computed using the SRC_WIDTH and BTSIZE bitfields
in the CTRLAx register.
Finally, the test to check whether the currently processed descriptor is
the last of the chain was wrong: for cyclic transfer, last_desc->lli.dscr
is NOT equal to zero, since set_desc_eol() is never called, but logically
equal to first_desc->txd.phys. This bug has a side effect on the
drivers/tty/serial/atmel_serial.c driver, which uses cyclic DMA transfer
to receive data. Since the DMA residue was wrong each time the DMA
transfer reaches the second (and last) period of the transfer, no more
data were received by the USART driver till the cyclic DMA transfer loops
back to the first period.
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Torsten Fleischer <torfl6749@gmail.com>
Tested-by: Jirí Prchal <jiri.prchal@aksignal.cz>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The AT91 HDMAC controller supports interleaved transfers through what's
called the Picture-in-Picture mode, which allows to transfer a squared
portion of a framebuffer.
This means that this interleaved transfer only supports interleaved
transfers which have a transfer size and ICGs that are fixed across all the
chunks.
While this is a quite drastic restriction of the interleaved transfers
compared to what the dmaengine API allows, this is still useful, and our
driver will only reject transfers that do not conform to this.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This patch fixes the following issues regarding to the calculation of the
residue:
1. The residue is always calculated for the current transfer even if the
cookie is associated to a pending transfer.
2. For scatter/gather DMA the calculation of the residue for the current
transfer doesn't include the bytes of the child descriptors that are already
transferred.
It only calculates the difference between the transfer's total length minus
the number of bytes that are already transferred for the current child
descriptor.
For example: There is a scatter/gather DMA transfer with a total length of
1 MByte. Getting the residue several times while the transfer is running shows
something like that:
1: residue = 975584
2: residue = 1002766
3: residue = 992627
4: residue = 983767
5: residue = 985694
6: residue = 1008094
7: residue = 1009741
8: residue = 1011195
3. The driver stores the residue but never resets it when starting a new
transfer.
For example: If there are two subsequent DMA transfers. The first one with
a total length of 1 MByte and the second one with a total length of 1 kByte.
Getting the residue for both transfers shows something like that:
transfer 1: residue = 975584
transfer 2: residue = 1048380
Changes from V1:
* Fixed coding style of the multi-line comments.
* Improved accuracy of the residue calculation when the transfer for the
first descriptor is active.
Changes from V2:
* Member 'tx_width' of 'struct at_desc' restored, because the transfer width
can't be derived from the source width when using "slave_sg".
The transfer width is needed for the calculation of the residue if either
the transfer of the first or the last descriptor is in progress.
In the case of a "memory_to_memory_sg" transfer (part of this patch
series) the transfer width of both descriptors may differ. Thus it is
required to additionally set 'tx_width' of the last descriptor.
* Added functions for multiply used calculations.
Signed-off-by: Torsten Fleischer <torfl6749@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
commit 54f8d501e8 ('dmaengine: remove DMA unmap from drivers')
refactored some code which resulted in an unused function in the at_hdmac
driver:
drivers/dma/at_hdmac_regs.h:350:23: warning: 'chan2parent' defined but
not used [-Wunused-function]
Fixes: 54f8d501e8 ('dmaengine: remove DMA unmap from drivers')
Signed-off-by: Olof Johansson <olof@lixom.net>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Vinod Koul <vinod.koul@Intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Add support for returning the residue for current transfer cookie by
reading the transfered buffer size(BTSIZE) in CTRLA register.
For a single buffer cookie, the descriptor length minus BTSIZE
can get the residue.
For a lli cookie, remain_desc will record remain descriptor length
when last descriptor finish, the remain_desc minus BTSIZE can get the
current residue.
If the cookie has completed successfully, the residue will be zero.
If the cookie is in progress, it will be the number of bytes yet to be transferred.
If get residue error, the cookie will be turn into error status.
Check dma fifo to see if data remain, let issue pending finish remain work if there is.
Signed-off-by: Elen Song <elen.song@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
In one dma transfer, the data transfer width can be configured and it is limited by source or destination peripheral width,
tx_width will save the transfer width, but for memcpy, either source or destination transfer width is taken as tx_width.
Signed-off-by: Elen Song <elen.song@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Update at_hdmac driver to support generic DMA device tree binding. Devices
can still request channel with dma_request_channel() then it doesn't break
DMA for non DT boards.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
dev_<level> calls take less code than dev_printk(KERN_<LEVEL>
and reducing object size is good.
Coalesce formats for easier grep.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Platform data for device drivers should be defined in
include/linux/platform_data/*.h, not in the architecture
and platform specific directories.
This moves such data out of the at91 include directories
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Vinod Koul <vinod.koul@linux.intel.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Dan Williams <djbw@fb.com>
The maxburst/chunk size was taken from the private slave DMA data structure.
Use the common API provided by DMA_SLAVE_CONFIG to setup src/dst maxburst
values.
The ctrla field is not needed anymore in the slave private structure nor the
header constants that were located in an architecture specific directory.
The at91sam9g45_devices.c file that was using this platform data is also
modified to remove this now useless data.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
This patch introduces DMA_SLAVE_CONFIG to at_hdmac Atmel DMA driver.
It is needed to fix a regression in the use of atmel-mci.c driver on Atmel
AT91 platforms brouth by e2b35f3:
"dmaengine/dw_dmac: Fix dw_dmac user drivers to adapt to slave_config changes"
We remove some parts of the private structure "at_dma_slave" and use the
information provided by "struct dma_slave_config": source/destination
peripheral registers and access width.
AT_DMA_SLAVE_WIDTH_* values used previously are not needed anymore as we
now use the standard ones. Although some conversion functions are needed to
match register expected values.
Some AT91 sub-architecture specific files are slightly touched by this patch
but it cannot be split because it can break compilation.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
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>
commit 463894705e deleted redundant
chan_id and chancnt initialization in dma drivers as this is done
in dma_async_device_register().
However, atc_enable_irq() relied on chan_id set before registering
the device, what left only channel 0 functional for this driver.
This patch introduces atc_enable/disable_chan_irq() as a variant
of atc_enable/disable_irq() with the channel as explicit argument.
Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Using a configuration structure simplify the finding of SoC
dependent parameters. Both platform data and device tree ids are
using these structures.
This will separate data from code and remove the need for an enum.
Idea from Grant Likely.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
We remove the use of platform data from DMA controller driver.
We now use of .id_table to distinguish between compatible
types. The two implementations allow to determine the
number of channels and the capabilities of the controller.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Cyclic property and paused state are encoded as bits in the channel status
bitfield. Tests of those bits are wrapped in convenient helper functions.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Save/restore dma controller state across a suspend-resume sequence.
The prepare() function will wait for the non-cyclic channels to become idle.
It also deals with cyclic operations with the start at next period while
resuming.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Pause and resume controls are useful for audio devices. This also returns
correct status from atc_tx_status() in case chan is paused.
Idea from dw_dmac patch by Linus Walleij.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
DMA controller has two AHB interfaces on the SOC internal
matrix.
It is more efficient to specialize each interface as the
access to memory can introduce latencies that are not compatible
with peripheral accesses requirements.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Now we use Buffer Transfer Completed interrupts. If we
want a chained buffer completed information, we setup the
ATC_IEN bit in CTRLB register in the lli.
This is done by set_desc_eol() function and used by
memcpy/slave_sg functions.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Drop at_hdmac's use of tx_list from struct dma_async_tx_descriptor in
preparation for removal of this field.
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This patch for at_hdmac adds the slave transfers capability to the Atmel DMA
controller available on some AT91 SOCs. This allow peripheral to memory and
memory to peripheral transfers with hardware handshaking.
Slave structure for controller specific information is passed through channel
private data. This at_dma_slave structure is defined in at_hdmac.h header file
and relative hardware definition are moved to this file from at_hdmac_regs.h.
Doing this we allow the channel configuration from platform definition code.
This work is intensively based on dw_dmac and several slave implementations.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This AHB DMA Controller (aka HDMA or DMAC on AT91 systems) is availlable on
at91sam9rl chip. It will be used on other products in the future.
This first release covers only the memory-to-memory tranfer type. This is the
only tranfer type supported by this chip. On other products, it will be used
also for peripheral DMA transfer (slave API support to come).
I used dmatest client without problem in different configurations to test it.
Full documentation for this controller can be found in the SAM9RL datasheet:
http://www.atmel.com/dyn/products/product_card.asp?part_id=4243
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
