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d2be75a52a
Add support for DMA controller of BCM2708 as used in the Raspberry Pi.
Currently it only supports cyclic DMA.
Signed-off-by: Florian Meier <florian.meier@koalo.de>
dmaengine: expand functionality by supporting scatter/gather transfers sdhci-bcm2708 and dma.c: fix for LITE channels
DMA: fix cyclic LITE length overflow bug
dmaengine: bcm2708: Remove chancnt affectations
Mirror bcm2835-dma.c commit 9eba5536a7:
chancnt 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: Noralf Trønnes <noralf@tronnes.org>
dmaengine: bcm2708: overwrite dreq only if it is not set
dreq is set when the DMA channel is fetched from Device Tree.
slave_id is set using dmaengine_slave_config().
Only overwrite dreq with slave_id if it is not set.
dreq/slave_id in the cyclic DMA case is not touched, because I don't
have hardware to test with.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
dmaengine: bcm2708: do device registration in the board file
Don't register the device in the driver. Do it in the board file.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
dmaengine: bcm2708: don't restrict DT support to ARCH_BCM2835
Both ARCH_BCM2835 and ARCH_BCM270x are built with OF now.
Add Device Tree support to the non ARCH_BCM2835 case.
Use the same driver name regardless of architecture.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
BCM270x_DT: add bcm2835-dma entry
Add Device Tree entry for bcm2835-dma.
The entry doesn't contain any resources since they are handled
by the arch/arm/mach-bcm270x/dma.c driver.
In non-DT mode, don't add the device in the board file.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
bcm2708-dmaengine: Add debug options
BCM270x: Add memory and irq resources to dmaengine device and DT
Prepare for merging of the legacy DMA API arch driver dma.c
with bcm2708-dmaengine by adding memory and irq resources both
to platform file device and Device Tree node.
Don't use BCM_DMAMAN_DRIVER_NAME so we don't have to include mach/dma.h
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
dmaengine: bcm2708: Merge with arch dma.c driver and disable dma.c
Merge the legacy DMA API driver with bcm2708-dmaengine.
This is done so we can use bcm2708_fb on ARCH_BCM2835 (mailbox
driver is also needed).
Changes to the dma.c code:
- Use BIT() macro.
- Cutdown some comments to one line.
- Add mutex to vc_dmaman and use this, since the dev lock is locked
during probing of the engine part.
- Add global g_dmaman variable since drvdata is used by the engine part.
- Restructure for readability:
vc_dmaman_chan_alloc()
vc_dmaman_chan_free()
bcm_dma_chan_free()
- Restructure bcm_dma_chan_alloc() to simplify error handling.
- Use device irq resources instead of hardcoded bcm_dma_irqs table.
- Remove dev_dmaman_register() and code it directly.
- Remove dev_dmaman_deregister() and code it directly.
- Simplify bcm_dmaman_probe() using devm_* functions.
- Get dmachans from DT if available.
- Keep 'dma.dmachans' module argument name for backwards compatibility.
Make it available on ARCH_BCM2835 as well.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
dmaengine: bcm2708: set residue_granularity field
bcm2708-dmaengine supports residue reporting at burst level
but didn't report this via the residue_granularity field.
Without this field set properly we get playback issues with I2S cards.
dmaengine: bcm2708-dmaengine: Fix memory leak when stopping a running transfer
bcm2708-dmaengine: Use more DMA channels (but not 12)
1) Only the bcm2708_fb drivers uses the legacy DMA API, and
it requires a BULK-capable channel, so all other types
(FAST, NORMAL and LITE) can be made available to the regular
DMA API.
2) DMA channels 11-14 share an interrupt. The driver can't
handle this, so don't use channels 12-14 (12 was used, probably
because it appears to have an interrupt, but in reality that
interrupt is for activity on ANY channel). This may explain
a lockup encountered when running out of DMA channels.
The combined effect of this patch is to leave 7 DMA channels
available + channel 0 for bcm2708_fb via the legacy API.
See: https://github.com/raspberrypi/linux/issues/1110
https://github.com/raspberrypi/linux/issues/1108
dmaengine: bcm2708: Make legacy API available for bcm2835-dma
bcm2708_fb uses the legacy DMA API, so in order to start using
bcm2835-dma, bcm2835-dma has to support the legacy API. Make this
possible by exporting bcm_dmaman_probe() and bcm_dmaman_remove().
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
dmaengine: bcm2708: Change DT compatible string
Both bcm2835-dma and bcm2708-dmaengine have the same compatible string.
So change compatible to "brcm,bcm2708-dma".
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
dmaengine: bcm2708: Remove driver but keep legacy API
Dropping non-DT support means we don't need this driver,
but we still need the legacy DMA API.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
bcm2708-dmaengine - Fix arm64 portability/build issues
dma-bcm2708: Fix module compilation of CONFIG_DMA_BCM2708
bcm2708-dmaengine.c defines functions like bcm_dma_start which are
defined as well in dma-bcm2708.h as inline versions when
CONFIG_DMA_BCM2708 is not defined. This works fine when
CONFIG_DMA_BCM2708 is built in, but when it is selected as module build
fails with redefinition errors because in the build system when
CONFIG_DMA_BCM2708 is selected as module, the macro becomes
CONFIG_DMA_BCM2708_MODULE.
This patch makes the header use CONFIG_DMA_BCM2708_MODULE too when
available.
Fixes https://github.com/raspberrypi/linux/issues/2056
Signed-off-by: Andrei Gherzan <andrei@gherzan.com>
bcm2708-dmaengine: Use platform_get_irq
The platform driver framework no longer creates IRQ resources for
platform devices because they are expected to use platform_get_irq.
This causes the bcm2808_fb acceleration to fail.
Fix the problem by calling platform_get_irq as intended.
See: https://github.com/raspberrypi/linux/issues/5131
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
Linux kernel
============
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