Nori, Sekhar wrote:
CPPI4.1 is an evolution over CPPI3.0.
I would call the 3.0-to-4.1 changes rather revolutionary, than evolutionary...
As I see it the following features evolved compared to 3.0
1. List management functions are handled by the DMA engine in 4.1 compared to 3.0
were the SW (driver) managed the same.
True, descriptor queues are handled by the queue manager now.
2. New performance modes (Generic RNDIS) got introduced.
Those new modes don't have anything to do with CPPI 4.1 itself -- they're part of USB XFER DMA. I think TI could well have kept using CPPI 3.0 and just added the new modes...
Beyond that the general processing of the DMA descriptors and functionality are
very similar between CPPI3.0 and 4.1.
There's nothing similar in the descriptor formats, there was no DMA controller, and neither queue nor buffer managers in CPPI 3.0.
DMA scheduler should be a configure once and leave.
Yes. I'm not arguing with that.
You should not need to use buffer manager as well. I am not sure if it is even supported on DA830.
No, it's not supported and the code that I posted doesn't support it either. I was just trying to outline the large difference between 3.0 and 4.1 that warrants a new driver, so I'm not sure why TI people started to argue...
Thanks, Sekhar
WBR, Sergei _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
