linux-toradex.git/drivers/dma/edma.c, branch v4.4.45

Merge branch 'fix/edma' into fixes

2015-12-10T03:13:43+00:00

dmaengine: edma: DT: Change reserved slot array from 16bit to 32bit type

2015-12-10T03:02:42+00:00

This change makes the DT file to be easier to read since the reserved slots
array does not need the '/bits/ 16' to be specified, which might confuse
some people.

Signed-off-by: Peter Ujfalusi 
Acked-by: Arnd Bergmann 
Acked-by: Rob Herring 
Acked-by: Tony Lindgren 
Signed-off-by: Vinod Koul

dmaengine: edma: DT: Change memcpy channel array from 16bit to 32bit type

2015-12-10T03:01:10+00:00

This change makes the DT file to be easier to read since the memcpy
channels array does not need the '/bits/ 16' to be specified, which might
confuse some people.

Signed-off-by: Peter Ujfalusi 
Acked-by: Arnd Bergmann 
Acked-by: Rob Herring 
Acked-by: Tony Lindgren 
Signed-off-by: Vinod Koul

dmaengine: edma: predecence bug in GET_NUM_QDMACH()

2015-11-16T03:37:35+00:00

The current code uses bits 0-2 instead of 4-6 as the comment says.

Fixes: 633e42b8c546 ('dmaengine: edma: Get qDMA channel information from HW also')
Signed-off-by: Dan Carpenter 
Acked-by: Peter Ujfalusi 
Signed-off-by: Vinod Koul

dmaengine: edma: fix build without CONFIG_OF

2015-11-16T03:35:31+00:00

During the edma rework, a build error was introduced for the
case that CONFIG_OF is disabled:

drivers/built-in.o: In function `edma_tc_set_pm_state':
:(.text+0x43bf0): undefined reference to `of_find_device_by_node'

As the edma_tc_set_pm_state() function does nothing in case
we are running without OF, this adds an IS_ENABLED() check
that turns the function into an empty stub then and avoids the
link error.

Signed-off-by: Arnd Bergmann 
Fixes: ca304fa9bb76 ("ARM/dmaengine: edma: Public API to use private struct pointer")
Acked-by: Peter Ujfalusi 
Signed-off-by: Vinod Koul

dmaengine: edma: Add dummy driver skeleton for edma3-tptc

2015-11-04T16:41:42+00:00

The eDMA3 TPTC does not need any software configuration, but it is a
separate IP block in the SoC. In order the omap hwmod core to be able to
handle the TPTC resources correctly in regards of PM we need to have a
driver loaded for it.
This patch will add a dummy driver skeleton without probe or remove
callbacks provided.

Signed-off-by: Peter Ujfalusi 
Reported-by: Olof Johansson 
Tested-by: Felipe Balbi 
Signed-off-by: Vinod Koul

dmaengine: edma: New device tree binding

2015-10-27T01:22:45+00:00

With the old binding and driver architecture we had many issues:
No way to assign eDMA channels to event queues, thus not able to tune the
system by moving specific DMA channels to low/high priority servicing. We
moved the cyclic channels to high priority within the code, but that was
just a workaround to this issue.
Memcopy was fundamentally broken: even if the driver scanned the DT/devices
in the booted system for direct DMA users (which is not effective when the
events are going through a crossbar) and created a map of 'used' channels,
this information was not really usable. Since via dmaengien API the eDMA
driver will be called with _some_ channel number, we would try to request
this channel when any channel is requested for memcpy. By luck we got
channel which is not used by any device most of the time so things worked,
but if a device would have been using the given channel, but not requested
it, the memcpy channel would have been waiting for HW event.
The old code had the am33xx/am43xx DMA event router handling embedded. This
should have been done in a separate driver since it is not part of the
actual eDMA IP.
There were no way to 'lock' PaRAM slots to be used by the DSP for example
when booting with DT.
In DT boot the edma node used more than one hwmod which is not a good
practice and the kernel prints warning because of this.

With the new bindings and the changes in the driver we can:
- No regression with Legacy binding and non DT boot
- DMA channels can be assigned to any TC (to set priority)
- PaRAM slots can be reserved for other cores to use
- Dynamic power management for CC and TCs, if only TC0 is used all other TC
  can be powered down for example

Signed-off-by: Peter Ujfalusi 
Signed-off-by: Vinod Koul

dmaengine: edma: Merge the of parsing functions

2015-10-27T01:22:45+00:00

Instead of nesting functions just merge them since the resulting function
is still small and readable.

Signed-off-by: Peter Ujfalusi 
Signed-off-by: Vinod Koul

dmaengine: edma: Do not allocate memory for edma_rsv_info in case of DT boot

2015-10-27T01:22:45+00:00

The channel/slot reservation is not supported when booted with DT so there
is not need to allocate memory.

Signed-off-by: Peter Ujfalusi 
Signed-off-by: Vinod Koul

dmaengine: edma: Refactor the dma device and channel struct initialization

2015-10-27T01:22:45+00:00

Move all code under one function to do the dma device and eDMA channel
related setup so they are not scattered around the driver.

Signed-off-by: Peter Ujfalusi 
Signed-off-by: Vinod Koul