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commit ed8b0d67f33518a16c6b2450fe5ebebf180c2d04 upstream.
This loop on EBCISR register was designed to clear IRQ sources before enabling
a DMA channel. This register is clear-on-read so a race condition can appear if
another channel is already active and has just finished its transfer.
Removing this read on EBCISR is fixing the issue as there is no case where an IRQ
could be pending: we already make sure that this register is drained at probe()
time and during resume.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit ca7fe2db892dcf91b2c72ee352eda4ff867903a7 upstream.
ML7831 is companion chip for Intel Atom E6xx series.
Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 275029353953c2117941ade84f02a2303912fad1 upstream.
Starting with v3.2 Jonathan reports that Xen crashes loading the ioatdma
driver. A debug run shows:
ioatdma 0000:00:16.4: desc[0]: (0x300cc7000->0x300cc7040) cookie: 0 flags: 0x2 ctl: 0x29 (op: 0 int_en: 1 compl: 1)
...
ioatdma 0000:00:16.4: ioat_get_current_completion: phys_complete: 0xcc7000
...which shows that in this environment GFP_KERNEL memory may be backed
by a 64-bit dma address. This breaks the driver's assumption that an
unsigned long should be able to contain the physical address for
descriptor memory. Switch to dma_addr_t which beyond being the right
size, is the true type for the data i.e. an io-virtual address
inidicating the engine's last processed descriptor.
Reported-by: Jonathan Nieder <jrnieder@gmail.com>
Reported-by: William Dauchy <wdauchy@gmail.com>
Tested-by: William Dauchy <wdauchy@gmail.com>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit bda3a47c886664e86ee14eb79e9072b9e341f575 upstream.
commit 463894705e4089d0ff69e7d877312d496ac70e5b 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>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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ARCH_MX3 was removed in commit a89cf59 :
"arm/imx: merge i.MX3 and i.MX6"
thus preventing to select MX3_IPU, thus preventing IPU and display
to work on i.MX3x SOC.
i.MX SDMA support is also affected.
Signed-off-by: Eric Bénard <eric@eukrea.com>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include <linux/module.h>
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include <linux/module.h>
net: sch_generic remove redundant use of <linux/module.h>
net: inet_timewait_sock doesnt need <linux/module.h>
...
Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
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* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (63 commits)
dmaengine: mid_dma: mask_peripheral_interrupt only when dmac is idle
dmaengine/ep93xx_dma: add module.h include
pch_dma: Reduce wasting memory
pch_dma: Fix suspend issue
dma/timberdale: free_irq() on an error path
dma: shdma: transfer based runtime PM
dmaengine: shdma: protect against the IRQ handler
dmaengine i.MX DMA/SDMA: add missing include of linux/module.h
dmaengine: delete redundant chan_id and chancnt initialization in dma drivers
dmaengine/amba-pl08x: Check txd->llis_va before freeing dma_pool
dmaengine/amba-pl08x: Add support for sg len greater than one for slave transfers
serial: sh-sci: don't filter on DMA device, use only channel ID
ARM: SAMSUNG: Remove Samsung specific enum type for dma direction
ASoC: Samsung: Update DMA interface
spi/s3c64xx: Merge dma control code
spi/s3c64xx: Add support DMA engine API
ARM: SAMSUNG: Remove S3C-PL330-DMA driver
ARM: S5P64X0: Use generic DMA PL330 driver
ARM: S5PC100: Use generic DMA PL330 driver
ARM: S5PV210: Use generic DMA PL330 driver
...
Fix up fairly trivial conflicts in
- arch/arm/mach-exynos4/{Kconfig,clock.c}
- arch/arm/mach-s5p64x0/dma.c
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To support multi-size buffers in the mx3_camera V4L2 driver we have to be
able to stop DMA on a channel without releasing descriptors and completely
halting the hardware. Use the DMA_PAUSE control to implement this mode.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Vinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
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Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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Fix files that were implicitly using module.h but not
calling it out for inclusion directly. We'll break those
once we remove the implicit presence otherwise
[With input from Uwe Kleine-König <u.kleine-koenig@pengutronix.de>]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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These files aren't just exporting symbols -- they are also defining
a MODULE_LICENSE etc. so give them the full module.h file.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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The mask_peripheral_interrupt is called when channel wants to mask the
interrupt. Move this to suspend as this masking affects other channels
as well. Not touching unmask here and unmask would still be done of
first channel use
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
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Due to module.h cleanup it is not anymore included implicitly. Drivers who
want to use it need to include it explicitly.
Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
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nr_channels is defined in "struct pch_dma".
and struct pch_dma_chan is defined in "struct pch_dma".
So, "sizeof(struct pch_dma_chan) * nr_channels" is unnecessary.
Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
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Currently, executing suspend/hibernation,
memory access violation occurs.
In pch_dma_save_regs() called by suspend(),
you can see the following code.
static void pch_dma_save_regs(struct pch_dma *pd)
{
snip...
list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
pd_chan = to_pd_chan(chan);
pd->ch_regs[i].dev_addr = channel_readl(pd_chan, DEV_ADDR);
pd->ch_regs[i].mem_addr = channel_readl(pd_chan, MEM_ADDR);
pd->ch_regs[i].size = channel_readl(pd_chan, SIZE);
pd->ch_regs[i].next = channel_readl(pd_chan, NEXT);
i++;
}
}
Max loop count is 12 defined at pci_table.
So, this caused memory access violation.
This patch fixes the issue
- Modify array size (MAX_CHAN_NR)
Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
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There was an error path that skipped the free_irq() step by mistake.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Currently the shdma dmaengine driver uses runtime PM to save power, when
no channel on the specific controller is requested by a user. This patch
switches the driver to count individual DMA transfers. That way the
controller can be powered down between transfers, even if some of its
channels are in use.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
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The IRQ handler of the shdma driver accesses common hardware registers,
that are also accessed from other contexts. Therefore access to them
has to be performed with interrupts disabled, not only with disabled
bottom halves.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
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Add missing include of linux/module.h to fix build error.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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dma_async_device_register will re-init chan_id and chancnt,
so whatever chan_id and chancnt are set in drivers, they will
be re-written by dma_async_device_register.
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Viresh Kumar <viresh.kumar@st.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Piotr Ziecik <kosmo@semihalf.com>
Cc: Yong Wang <yong.y.wang@intel.com>
Cc: Jaswinder Singh <jassi.brar@samsung.com>
Cc: Pelagicore AB <info@pelagicore.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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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>
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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>
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This patch adds DMA_CYCLIC capability that is used for audio driver.
DMA driver activated with it reuses the dma requests that were submitted
through tx_submit().
Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Original code carries out the start operation after flush operation.
But start operation is not required for DMA_TERMINATE_ALL command.
So, this patch removes the unnecessary start operation and only carries out
the flush operation for handling DMA_TERMINATE_ALL command.
Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
[Fixed typos in changelog]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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This patch updates following 3 items.
1. Removes unneccessary code.
2. Add AMBA, PL330 configuration
3. Change the meaning of 'peri_id' variable
from PL330 event number to specific dma id by user.
Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The bank_lock can be taken in atomic context (irq handling)
and therefore cannot be preempted on -rt - annotate it.
In mainline this change documents the low level nature of
the lock - otherwise there's no functional difference. Lockdep
and Sparse checking will work as usual.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: kernel@pengutronix.de
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: http://lkml.kernel.org/r/1311949627-13260-1-git-send-email-u.kleine-koenig@pengutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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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>
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Prepared descriptors that are not submitted will not be freed. Add
prepared descriptor to a list to be able to release them upon
dmaengine_terminate_all().
Signed-off-by: Per Forlin <per.forlin@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The client list may exist in two lists at the same time. This makes free
fail since the same desc is freed multiple times. Remove desc from
client list when adding it to the pending queue. Move free of client owned
descriptors from free_dma() to terminate_all().
Unable to handle kernel paging request at virtual address 00100104
pgd = dea8c000
[00100104] *pgd=1ea62831, *pte=00000000, *ppte=00000000
Internal error: Oops: 817 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 Not tainted (3.1.0-rc3+ #58)
PC is at d40_free_chan_resources+0x64/0x330
Signed-off-by: Per Forlin <per.forlin@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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d40_desc_free() already calls d40_pool_lli_free().
Signed-off-by: Per Forlin <per.forlin@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Signed-off-by: Per Forlin <per.forlin@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Prepared descriptors that are not submitted will not be freed. Add
prepared descriptor to a list to be able to release them upon
dmaengine_terminate_all().
Signed-off-by: Per Forlin <per.forlin@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The client list may exist in two lists at the same time. This makes free
fail since the same desc is freed multiple times. Remove desc from
client list when adding it to the pending queue. Move free of client owned
descriptors from free_dma() to terminate_all().
Unable to handle kernel paging request at virtual address 00100104
pgd = dea8c000
[00100104] *pgd=1ea62831, *pte=00000000, *ppte=00000000
Internal error: Oops: 817 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 Not tainted (3.1.0-rc3+ #58)
PC is at d40_free_chan_resources+0x64/0x330
Signed-off-by: Per Forlin <per.forlin@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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d40_desc_free() already calls d40_pool_lli_free().
Signed-off-by: Per Forlin <per.forlin@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Signed-off-by: Per Forlin <per.forlin@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Fixed trivial conflicts in drivers/dma/amba-pl08x.c
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The firmware blob may not be available when the driver
probes. Instead of blocking the whole kernel use
request_firmware_nowait() and continue without firmware.
The ROM scripts can already be used then if available.
For the devicetree case the ROM scripts are not available,
still the probe function should not block. The driver
will be unusable in this case, but we have no way of
detecting this properly. The configuration of the dma
channels will fail, so nothing bad should happen.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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If we do not have a firmare script for a given transfer,
the setup of this channel must fail. For this the script
addresses have to be < 0 initially, not 0.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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channel0 of the sdma engine is the configuration channel. It
is a shared resource and thus must be protected by a mutex.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Making dmatest threads freezable allows its use for system PM testing.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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