DM6467 EDMA channel conflict

Jayakrishnan

Expert 2790 points

I want to use DM6467 EDMA to transfer frame data from PCI memory to DDR2.

I am using the PCI Boot Driver from TI.

My application uses arch/arm/mach-davinci/dma.c driver for allocating EDMA channels.

Since the EDMA channels are controlled by two drivers, there is a chance of conflict.

Is there a way in the arch/arm/mach-davinci/dma.c to exclude some channel/channels from being dynamically allocated?,

So that channel can be safely used by the PCI boot driver. Kindly suggest.

Regards

0 Sekhar Nori over 15 years ago

Hi JK,

You can use this mechanism to keep some DMA channels/PaRAM slots off-limits for Linux DMA driver.

Thanks,

Sekhar

0 Jayakrishnan over 15 years ago in reply to Sekhar Nori

Expert 2790 points

Hi Sekhar

I checked the above link, but could not get much information.

In the DM646x dma driver, the EDMA channels are divided in to two subsets, I believe.

One subset is controlled by the ARM and another controlled by DSP. ARM side allocates EDMA channels dynamically

from its subset. Am I correct? If So, is it possible for a third master , like PCI driver, to control the EDMA resources?

If I block any one channel from the ARM subset, can I make sure that the same channel will not be taken over by the DSP?

Regards

0 lastshad0w over 12 years ago

Expert 1385 points

JK,

I am working on transfering frame data from PCI memory to DDR2.

But I get poor performance(about 25MBtye/s), I will appreciated if you tell me the method which you used.

Thanks!

Jack

Processors forum