Lloyd Sargent wrote: > On Friday 02 November 2007 09:07, Denis Oliver Kropp wrote: >> Do you think the DMA engine would be faster than the DSP? I thought >> memory throughput would be the bottleneck anyhow. For now it would be >> easier to maintain one accelerator only. Syncing and maintaining command >> ordering is not really supported yet for multiple accelerators. > > Yah, memory throughput is a bottleneck (we haven't run into it, but it is > obvious it will be) - doesn't matter how many busses there are. Honestly, I > only SUSPECT DMA is faster, but have no proof. > > It sounds like you did something that is independent of the T.I. DSP > software - how compatible is it? Can I run DFB accelerator and MPEG decoder? > Or is it one or the other? I have had conflicting stories from T.I. in > regards to multiple DSP apps.
It is completely independent of TI's DSP software, no dsplink/bios etc. You cannot run any other DSP code, e.g. TIs video codec, but we're working on our own MPEG decoder and have command queues to manage multiple DSP 'apps', i.e. commands issued by DFB or the video code. >> Does the DMA engine support anything beyond simple 2D block moves in >> memory? > > Yes. It supports 3D block moves. It is actually pretty spiffy. I was talking > to the T.I. engineer about it last year about moving a section of graphics > and he said "oh, use the DMA". I jumped in and said "But DMA is 2D only it > won't work!" Then he smiled and said "We made changes. It supports not only > length, but width" Why 3D? Traditional DMA would be 1D with start and length. 2D would be start, line length, actual width and number of lines. >> Maybe 8/16/32 bit wise compare/skip, i.e. color keying? > > Nooo, I don't recall THAT being in the DMA... or are you talking about > something else? That would make the DSP the superior choice of course. I really meant comparing each word to be copied with a reference value before actually writing it to the destination. Simple rectangular fills and copies would not be enough to fully accelerate a GUI. -- Best regards, Denis Oliver Kropp .------------------------------------------. | DirectFB - Hardware accelerated graphics | | http://www.directfb.org/ | "------------------------------------------" _______________________________________________ directfb-users mailing list [email protected] http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-users
