16 May
2011
16 May
'11
9:15 p.m.
Hi All,
On Fri, May 13, 2011 at 5:26 PM, Ben Gardiner bengardiner@nanometrics.ca wrote:
[...] Does anyone have any clues why ping-pong buffers on da850 to the McASP would work? Or any clues why the patches are broken?
To answer my own question: the reason ping-pong buffering was not working is because the SRAM allocator being used was allocating buffers from the "ARM local RAM" block @0xFFFF0000 which is not addressable by the DMA engine -- according to SPRS586.
Ping-pong buffers work when I substitute the allocator for one that allocates from the 'Shared RAM' block @0x80000000 using Subhasish Ghosh's patch "davinci: changed SRAM allocator to shared ram."
Best Regards, Ben Gardiner
--- Nanometrics Inc. http://www.nanometrics.ca