in dma_slave_config, which is incompatible with the way that the
dmaengine API normally works.
I've had a closer look at the existing code now and found that all
slave drivers that pass a slave_id in dma_slave_config for SH do that
right after passing the same ID into shdma_chan_filter, so we can just
rely on that. However, the various shdma drivers currently do not
remember the slave ID that was passed into the filter function when
used in non-DT mode and only check the value to find a matching channel,
unlike all other drivers.
There might still be drivers that are not part of the kernel that rely
on setting the slave_id to some other value, so to be on the safe side,
this adds another 'real_slave_id' field to shdma_chan that remembers
the ID and uses it when a driver passes a zero slave_id in dma_slave_config,
like most drivers do.
Eventually, the real_slave_id and slave_id fields should just get merged
into one field, but that requires other changes.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Split the device_control callback of the Super-H DMA driver to make use of the
newly introduced callbacks, that will eventually be used to retrieve slave
capabilities.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This patch fixes a race condition about a list of shdma-base driver.
If we don't apply this patch, a dma slave driver (especially a usb
peripheral driver) may not be able to start the transfer.
If a dma slave driver has a callback, __ld_cleanup() will call
the callback before this driver removes the list. After the callback,
since the return value of __ld_cleanup() is not zero,
shdma_chan_ld_cleanup() calls __ld_cleanup() again. And, __ld_clean()
will removes the list.
At this time, if a dma slave driver calls dmaengine_submit() before
this driver removes the list, this driver will set schan->pm_state
to SHDMA_PM_PENDING in shdma_tx_submit(). And then, even if a dma
slave driver calls dma_async_issue_pending(), this driver don't
start the transfer because the schan->pm_state is SHDMA_PM_PENDING
in shdma_issue_pending().
So, this patch adds a new condition in __ld_clean() to check if the
schan->pm_state is SHDMA_PM_PENDING or not.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
chanctnt is already filled by dma_async_device_register, which uses the channel
list to know how much channels there is.
Since it's already filled, we can safely remove it from the drivers' probe
function.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The argument is always set to NULL and never used. Remove it.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The sg list used to prepare cyclic DMA descriptors is currently
allocated statically on the stack as an array of 32 elements. This makes
the shdma_prep_dma_cyclic() function consume a lot of stack space, as
reported by the compiler:
drivers/dma/sh/shdma-base.c: In function ‘shdma_prep_dma_cyclic’:
drivers/dma/sh/shdma-base.c:715:1: warning: the frame size of 1056 bytes
is larger than 1024 bytes [-Wframe-larger-than=]
Given the limited Linux kernel stack size, this could lead to stack
overflows. Fix the problem by allocating the sg list dynamically.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The shdma_chan_filter() function relies on the DMA channel being
embedded in an shdma_chan structure. If this assumption isn't true, for
instance when the system contains DMA channels supported by an unrelated
driver, the function will crash.
Avoid this by returning false directly when the channel belongs to an
unrelated device.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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>
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 the %zu and %pad printk specifiers to print size_t and dma_addr_t
variables, and cast pointers to uintptr_t instead of unsigned int where
applicable. This fixes warnings on platforms where pointers and/or
dma_addr_t have a different size than int
Cc: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This facilitates DMAC DT support by eliminating the need in AUXDATA and
avoiding creating complex DT data. This also fits well with DMAC devices,
of which SoCs often have multiple identical copies and it is perfectly
valid to use a single configuration data set for all of them.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Switch shdma to using devm_* managed functions for allocation of memory,
requesting IRQs, mapping IO resources etc.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This patch adds Device Tree support to the shdma driver. No special DT
properties are used, only standard DMA DT bindings are implemented. Since
shdma controllers reside on SoCs, their configuration is SoC-specific and
shall be passed to the driver from the SoC platform data, using the
auxdata procedure.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
the variable chan is dereferenced in line 635, so it is no reason to check
null again in line 641.
Signed-off-by: Cong Ding <dinggnu@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The recent shdma driver split has mistakenly removed support for partial
DMA transfer size calculation on forced termination. This patch restores
it.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Vinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch extends the sh dmaengine driver to support the preferred channel
selection and configuration method, instead of using the "private" field
from struct dma_chan. We add a standard filter function to be used by
slave drivers instead of implementing their own ones, and add support for
the DMA_SLAVE_CONFIG control operation, which must accompany the new
channel selection method. We still support the legacy .private channel
allocation method to cater for a smooth driver migration.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
[applied a trvial checkpath fix]
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Initially struct shdma_slave has been introduced with the only member - an
unsigned slave ID - to describe common properties of DMA slaves in an
extensible way. However, experience shows, that a slave ID is indeed the
only parameter, needed to identify DMA slaves. This is also, what is used
by the core dmaengine API in struct dma_slave_config. We switch to using
the slave_id directly, instead of passing a pointer to struct shdma_slave
to improve compatibility with the core. We also make the slave_id signed
for easier error checking.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Using struct dma_chan::private is deprecated. To update the shdma driver to
stop using it we first have to eliminate internal runtime uses of it. After
that we will also be able to stop using it for channel configuration.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
This patch extracts code from shdma.c, that does not directly deal with
hardware implementation details and can be re-used with diverse DMA
controller variants, found on SH-based SoCs.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Arnd Bergmann