Hello,
I'm working with DaVinci DM6467, using ARM running linux, and
CodecEngine as the interface between ARM and DSP.
My application is doing audio and video encoding in parallel in two
different threads.
I'm also using CMEM version 2.10 for continuous buffers allocation.
The problem is that, in some situation, the CMEM buffer physical address
viewed by ARM (using CMEM_getPhys()) is different than the physical
address sent to DSP (translated by CodecEngine).
Scenario where ArmPhyAddr != DspPhyAddr:
===================================
In my application, I open CodecEngine and then open two codecs on the
DSP: VIDENC1 and SPHENC1.
In the beginning both codecs are running in two different threads, and
for each of them we keep a CMEM buffers pool in ARM for their IO
buffers.
When the app starts running, for each Codec it take a single buffer from
the relevant Cmem pool, and use only this buffer for all the run.
In the beginning the physical addresses viewed by ARM and DSP are equal.
After a while, we do the following sequence of closing and opening the
codecs:
1. Close and open the video codec
- VIDENC1_delete()
- Return the CMEM buf of VIDENC to the pool.
- Take a new CMEM buffer from the pool to be used for VIDENC.
- VIDENC_create()
- Running video processing of a stream ...
2. Close and open the speech codec:
- SPHENC1_delete()
- Return the CMEM buf of SPHENC to the pool.
- Take a new CMEM buffer from the pool to be used for SPHENC.
- SPHENC_create()
- Running speech processing of a stream ...
After doing this sequence and continue running the video and audio
processing.
Now on the SPHENC codec, the CMEM buffer physical address viewed by ARM
is different than the one viewed by the DSP for the same buffer.
In addition I see that there is a constant offset between them which is
the size of a CMEM buffer used for the speech (in our case 258048).
That means that the same virtual address in the ARM is translated in ARM
to different physical address than the one translated by CodecEngine.
It seems like two different translation tables are used, and they are
not synchronized.
Our CMEM pool for the speech usage is made of 3 buffers of size 258048.
Does anyone know what can cause this problem? To me it seems like CMEM
problem, however, when checking in TI site I see that version 2_10 that
I'm using is currently the official version.
Thanks in advance for any help,
_______________________________________________
Davinci-linux-open-source mailing list
Davinci-linux-open-source@linux.davincidsp.com
http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
