Hi everyone,
I'm new to the forum. We have our own custom DM3725 platform and we are developing a realtime audio application with very low latency requirements (musical instrument). So McBSP is directly driven by DSP that make most of the critical work. But we need also to have some audio work done on Arm. So we'd like to send and receive an audio stream from Arm.
On Arm we are running Linux 2.26.2x, using DSPLink 1.61 with PROC component only just to load DSP executable and then the communication between the two processors is done by shared memory.
To implement an audio stream we'd like to write an ALSA driver that use DSP as an Audio board and to do this we need to send an interrupt from DSP to ARM. We have found two solutions to do this: using mailbox hardware peripheral inside Dm3725 or using GPIO making a shortcircuit between 2 ports, one controlled by Arm (to receive the interrupt) and one by DSP (that control the signal),
Wasting mailbox hardware for such a task seems a pity (even if we don't plan to use it at the moment).
Another solution would be to use DSPLink services, certainly easier, but the ALSA solution make it standard under Linux world.
If DSPLink is compiled with only PROC support can we be sure that it's not using mailbox peripheral?
Which is the best method to send an interrupt from DSP to ARM? Is there another way to do it?
Any help or suggestion welcome.
Marco