I received a report this morning from one of the Novena developers that
the behaviour of the iMX6 ASoC codec driver (using imx-pcm-dma.c) was
sub-optimal under high system load.
While there are issues relating to system load remaining, upon reviewing
the ASoC imx-pcm-dma.c driver, it was noticed that it not using the
residue support, because SDMA doesn't support it. This has the effect
that SDMA has to make multiple calls into the ASoC and ALSA code, one
for each period.
Since ALSA's snd_pcm_elapsed() does not need to be called multiple times
and it is entirely sufficient to call it once to update ALSA with the
current buffer position via the pointer method, we can do better here.
We can also avoid stopping the DMA entirely, just like real cyclic DMA
implementations behave. While this means that we replay some old samples,
this is a nicer behaviour than having audio stop and restart.
The changes to achieve this are relatively minor - imx-sdma.c can track
where the DMA is to the nearest descriptor boundary - it does this
already when deciding how many callbacks to issue. In doing this,
buf_tail always points at the descriptor which will complete next.
The residue is defined by the bytes remaining to the end of the buffer,
when the buffer is viewed as a single block of memory [start...end].
So, when we start out, there's a full buffer worth of residue, and this
counts down as we approach the end of the buffer, eventually becoming
zero at the end, before returning to the full buffer worth when we
wrap back to the start.
Moving the walking of the descriptors into the interrupt handler means
that we can update the BD_DONE flag at interrupt time, thus avoiding
a delayed tasklet stopping the cyclic DMA.
This means that the residue can be calculated from (total descriptors -
buf_tail) * descriptor size. This is what the change below does. We
update imx-pcm-dma.c to remove the NO_RESIDUE flag since we now provide
the residue.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
When a 0-length packet is received on the bus, desc->pd0 yields 1,
which confuses the driver's users. This information is clearly wrong
and not in accordance to the datasheet, but it's been observed on an
AM335x board, very reproducible.
Fix this by looking at bit 19 in PD2 of the completed packet. This bit
will tell us if a zero-length packet was received on a queue. If it's
set, ignore the value in PD0 and report a total length of 0 instead.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
dynamic stack allocation in kernel is considered bad as kernel stack is low and
we get warns on few archs as reported by kbuild test robot
>> drivers/dma/sh/shdma-base.c:671:32: sparse: Variable length array is used.
>> drivers/dma/sh/shdma-base.c:701:1: warning: 'shdma_prep_dma_cyclic' uses
>> dynamic stack allocation [enabled by default]
Fix this by making a static array of 32 which should be sufficient for
shdma_prep_dma_cyclic which only user in kernel is audio and 32 periods for
audio seems quite sufficient atm
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
As documented in Documentation/printk-formats.txt we should use %zu/%zx
specifiers for size_t type variables for the code to compile on different
architectures. This is uncovered as COMPILE_TEST has been enabled recently for
this driver
drivers/dma/sh/shdma-base.c: In function 'shdma_prep_dma_cyclic':
>> drivers/dma/sh/shdma-base.c:683:4: warning: format '%d' expects argument of
>> type 'int', but argument 4 has type 'size_t' [-Wformat=]
__func__, buf_len, period_len, slave_id);
>> drivers/dma/sh/shdma-base.c:683:4: warning: format '%d' expects argument of
>> type 'int', but argument 5 has type 'size_t' [-Wformat=]
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
kbuild test robot reports that shdma_prep_dma_cyclic should be static, since
symbol is not declared, quick check revails that is the case
>> drivers/dma/sh/shdma-base.c:660:32: sparse: symbol 'shdma_prep_dma_cyclic'
>> was not declared. Should it be static?
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
SoC-near driver changes that we're merging through our tree. Mostly
because they depend on other changes we have staged, but in some cases
because the driver maintainers preferred that we did it this way.
This contains a largeish cleanup series of the omap_l3_noc bus driver,
cpuidle rework for Exynos, some reset driver conversions and a long
branch of TI EDMA fixes and cleanups, with more to come next release.
The TI EDMA cleanups is a shared branch with the dmaengine tree, with
a handful of Davinci-specific fixes on top.
After discussion at last year's KS (and some more on the mailing lists),
we are here adding a drivers/soc directory. The purpose of this is
to keep per-vendor shared code that's needed by different drivers but
that doesn't fit into the MFD (nor drivers/platform) model. We expect
to keep merging contents for this hierarchy through arm-soc so we can
keep an eye on what the vendors keep adding here and not making it a
free-for-all to shove in crazy stuff.
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Merge tag 'drivers-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc into next
Pull ARM SoC driver changes from Olof Johansson:
"SoC-near driver changes that we're merging through our tree. Mostly
because they depend on other changes we have staged, but in some cases
because the driver maintainers preferred that we did it this way.
This contains a largeish cleanup series of the omap_l3_noc bus driver,
cpuidle rework for Exynos, some reset driver conversions and a long
branch of TI EDMA fixes and cleanups, with more to come next release.
The TI EDMA cleanups is a shared branch with the dmaengine tree, with
a handful of Davinci-specific fixes on top.
After discussion at last year's KS (and some more on the mailing
lists), we are here adding a drivers/soc directory. The purpose of
this is to keep per-vendor shared code that's needed by different
drivers but that doesn't fit into the MFD (nor drivers/platform)
model. We expect to keep merging contents for this hierarchy through
arm-soc so we can keep an eye on what the vendors keep adding here and
not making it a free-for-all to shove in crazy stuff"
* tag 'drivers-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (101 commits)
cpufreq: exynos: Fix driver compilation with ARCH_MULTIPLATFORM
tty: serial: msm: Remove direct access to GSBI
power: reset: keystone-reset: introduce keystone reset driver
Documentation: dt: add bindings for keystone pll control controller
Documentation: dt: add bindings for keystone reset driver
soc: qcom: fix of_device_id table
ARM: EXYNOS: Fix kernel panic when unplugging CPU1 on exynos
ARM: EXYNOS: Move the driver to drivers/cpuidle directory
ARM: EXYNOS: Cleanup all unneeded headers from cpuidle.c
ARM: EXYNOS: Pass the AFTR callback to the platform_data
ARM: EXYNOS: Move S5P_CHECK_SLEEP into pm.c
ARM: EXYNOS: Move the power sequence call in the cpu_pm notifier
ARM: EXYNOS: Move the AFTR state function into pm.c
ARM: EXYNOS: Encapsulate the AFTR code into a function
ARM: EXYNOS: Disable cpuidle for exynos5440
ARM: EXYNOS: Encapsulate boot vector code into a function for cpuidle
ARM: EXYNOS: Pass wakeup mask parameter to function for cpuidle
ARM: EXYNOS: Remove ifdef for scu_enable in pm
ARM: EXYNOS: Move scu_enable in the cpu_pm notifier
ARM: EXYNOS: Use the cpu_pm notifier for pm
...
The APBX-DMA block is also found on MX6Q/MX6DL chips.
Update the help text accordingly.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
linux/err.h isn't implicitly included by the current headers on all
platforms, resulting in compilation failures due to implicit
declarations of IS_ERR and PTR_ERR. Fix this by including linux/err.h.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
linux/err.h isn't implicitly included by the current headers on all
platforms, resulting in compilation failures due to implicit
declarations of IS_ERR and PTR_ERR. Fix this by including linux/err.h.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
linux/err.h isn't implicitly included by the current headers on all
platforms, resulting in compilation failures due to implicit
declarations of IS_ERR and PTR_ERR. Fix this by including linux/err.h.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Many audio interface drivers require support of cyclic transfers to work
correctly, for example Samsung ASoC DMA driver. This patch adds support
for cyclic transfers to the s3c24xx-dma driver
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Due to redundant 'break' in loop driver processed only first chunk.
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
In cyclic dma tx's handler sdma_handle_channel_loop(),
SDMA channel statue is set to either DMA_ERROR or DMA_IN_PROGRESS
based on each period's status. This has the following issues:
1) If one period's status is BD_RROR, then channel status
will be set to DMA_ERROR, but it will be overwritten to DMA_IN_PROGRESS
if the following periods are OK.
2) DMA client may call sdma_control(DMA_TERMINATE_ALL) to stop the cyclic dma
operation, sdma channel status will be set to DMA_ERROR,
but if after this handler is called, then again the channel status will be overwritten
to DMA_IN_PROGRESS. Then the following dmaengine_prep_dma_cyclic() will always fail,
as channel status is DMA_IN_PROGRESS.
As in cyclic dma tx, channel status will be initially set to DMA_IN_PROGRESS,
driver only needs to change it to DMA_ERROR, when something wrong happens
(one period status is wrong, or stoped by client explicitly).
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Pull slave-dmaengine fixes from Vinod Koul:
"We have three small fixes.
First one from Andy reverts the devm_request irq as we need to ensure
the tasklet is killed after irq is freed, so we need to do free irq in
our code. Other two from Arnd are fixing the compilation issue in
omap and sa11x0 drivers with ARM randconfigs"
* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: sa11x0: remove broken #ifdef
dmaengine: omap: hide filter_fn for built-in drivers
dmaengine: dw: went back to plain {request,free}_irq() calls
commit 4828b493 introduced COMPILE_TEST for this driver and this cause compile
failure on alpha as kzalloc wasnt availble for this arch in included header, so
explictly add slab.h
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
dma_async_device_register() may return non-zero error code. In such case we
have to follow error path.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The commit dbde5c29 "dw_dmac: use devm_* functions to simplify code" turns
probe function to use devm_* helpers and simultaneously brings a regression.
We have to 1) call clk_disable_unprepare() on error path, and 2) check error
code of clk_enable_prepare(). First part was done in the original code, second
one is an update.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
hclk signal is a bus clock. So, it means we have to have it enabled during
access to the DMA controller. This patch makes sure that we enable clock before
access to the device, though it currently works on Intel hardware.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The pch_dma driver is for a companion chip to the Intel Atom E600
series processors. These are 32-bit x86 processors so the driver is
only needed on X86_32. Add COMPILE_TEST as an alternative, so that the
driver can still be build-tested elsewhere.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Introduce support for slave s/g transfer preparation and the associated
device control callback in the MPC512x DMA controller driver, which adds
support for data transfers between memory and peripheral I/O to the
previously supported mem-to-mem transfers.
Signed-off-by: Alexander Popov <a13xp0p0v88@gmail.com>
[fixed subsytem name]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The count which is used to get_unmap_data maybe not the same as the
count computed in dmaengine_unmap which causes to free data in a
wrong pool.
This patch fixes this issue by keeping the map count with unmap_data
structure and use this count to get the pool.
Cc: <stable@vger.kernel.org>
Signed-off-by: Xuelin Shi <xuelin.shi@freescale.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
We need to use writel() instead of writel_relaxed() when starting
a channel, to ensure all the descriptors have been flushed before
the activation.
While at it, remove the unneeded read-modify-write and make the
code simpler.
Cc: <stable@vger.kernel.org>
Signed-off-by: Lior Amsalem <alior@marvell.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The sa11x0_dma_pm_ops unconditionally reference sa11x0_dma_resume
and sa11x0_dma_suspend, which currently breaks if CONFIG_PM_SLEEP
is disabled.
There is probably a better way to remove the reference in this
case, but the safe choice is to have the suspend/resume code always
built in the driver.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: dmaengine@vger.kernel.org
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Don't use DEFINE_PCI_DEVICE_TABLE macro, because this macro
is deprecated.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The commit dbde5c29 "dw_dmac: use devm_* functions to simplify code" turns
probe function to use devm_* helpers and simultaneously brings a regression. We
need to ensure irq is disabled, followed by ensuring that don't schedule any
more tasklets and then its safe to use tasklet_kill().
The free_irq() will ensure that the irq is disabled and also wait till all
scheduled interrupts are executed by invoking synchronize_irq(). So we need to
only do tasklet_kill() after invoking free_irq().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable@vger.kernel.org # v3.11+
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Clients may still be active in the early phase of system PM, thus we
need to move the suspend operations to the late system PM phase.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
A channel can accommodate more than one transaction, each consisting of
multiple descriptors, the last of which has the DCMD_ENDIRQEN bit set.
In order to report the channel's residue, we hence have to walk the
list of running descriptors, look for those which match the cookie,
and then try to find the descriptor which defines upper and lower
boundaries that embrace the current transport pointer. Once it is found,
walk forward until we find the descriptor that tells us about the end of
a transaction via a set DCMD_ENDIRQEN bit.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Make sure to handle register context save/restore when needed from
system PM callbacks.
Previously we solely trusted the device to reside in in-active state
while the system suspend callback were invoked, which is just too
optimistic.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Converting to the PM macros makes us simplify and remove some code.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
While probing, don't rely on CONFIG_PM_RUNTIME to be configured.
Instead, let's power up the device and make it fully operational.
Update the runtime PM status to reflect the active state.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The runtime PM resume callback needs to be executed while holding the
spinlock, make sure to maintain this for the pause operation as well.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The commit 4501fe61 "dma: dw: Add suspend and resume handling for PCI mode
DW_DMAC." introduces system power management callbacks. Regarding to commit
f78c4cff "PM / Sleep: Add macro to define common late/early system PM
callbacks" we have nice macro to setup dev_pm_ops structure. This patch
converts a driver to use the macro.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
There is no need to use *_noirq version of suspend and resume PM callbacks. The
suspend_late / resume_early suit better (it was discussed in [1]) and in future
could be used for runtime PM support.
[1] http://www.spinics.net/lists/kernel/msg1650974.html
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Fix mpc_dma_probe() error path and mpc_dma_remove(): manually free IRQs and
dispose IRQ mappings before devm_* takes care of other resources.
Moreover replace devm_request_irq() with request_irq() since there is no need
to use it because the original code always frees IRQ manually with
devm_free_irq(). Replace devm_free_irq() with free_irq() accordingly.
Signed-off-by: Alexander Popov <a13xp0p0v88@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
MPC512x and MPC8308 have similar DMA controllers, but are independent SoCs.
DMA controller driver should have separate 'compatible' values for these SoCs.
Signed-off-by: Alexander Popov <a13xp0p0v88@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Concentrate the specific code for MPC8308 in the 'if' branch
and handle MPC512x in the 'else' branch.
This modification only reorders instructions but doesn't change behaviour.
Signed-off-by: Alexander Popov <a13xp0p0v88@gmail.com>
Acked-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
These functions will be modified in the next patch in the series. By moving the
function in a patch separate from the changes, it will make review easier.
Signed-off-by: Hongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: Qiang Liu <qiang.liu@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
There are several places where descriptors are freed using identical code.
This patch puts this code into a function to reduce code duplication.
Signed-off-by: Hongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: Qiang Liu <qiang.liu@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Delete attribute DMA_INTERRUPT because fsldma doesn't support this function,
exception will be thrown if talitos is used to offload xor at the same time.
Signed-off-by: Hongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: Qiang Liu <qiang.liu@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Methods of accessing DMA controller registers are inconsistent, some registers
are accessed by DMA_IN/OUT directly, while others are accessed by functions
get/set_* which are wrappers of DMA_IN/OUT, and even for the BCR register, it
is read by get_bcr but written by DMA_OUT.
This patch unifies the inconsistent methods, all registers are accessed by
get/set_* now.
Signed-off-by: Hongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Some codes are calling chan_dbg with FSL_DMA_LD_DEBUG surrounded, it is really
unnecessary to use such a macro because chan_dbg is a wrapper of dev_dbg, we do
have corresponding DEBUG macro to switch on/off dev_dbg, and most of the other
codes are also calling chan_dbg directly without using FSL_DMA_LD_DEBUG.
Signed-off-by: Hongbo Zhang <hongbo.zhang@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This patch add cyclic transfer support and enables dmaengine_prep_dma_cyclic()
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
[reflown changelog for readablity]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Current shdma is using "last" which indicates last desc which needs to have
callback function. But that desc's chunks is always 1, we can use it as finder
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
[reflown changelog for readablity]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Use sizeof(*var) instead of sizeof(type) when calling devm_k*alloc().
This avoids using the wrong type as was done to allocate the physical
channels array.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
