#12400 NORM 13.1.0: Determine MMP3 audio buffer parameters
Zarro Boogs per Child
bugtracker at laptop.org
Fri Jan 11 12:32:30 EST 2013
#12400: Determine MMP3 audio buffer parameters
--------------------------------+-------------------------------------------
Reporter: dsd | Owner: saadia
Type: defect | Status: new
Priority: normal | Milestone: 13.1.0
Component: kernel | Version: not specified
Resolution: | Keywords:
Next_action: diagnose | Verified: 0
Deployment_affected: | Blockedby:
Blocking: |
--------------------------------+-------------------------------------------
Comment(by wmb at firmworks.com):
You can't use all of the SRAM for buffers because you need some for ADMA
descriptors.
Maybe qseven works with 64k because no SRAM is earmarked for CForth, thus
it still has room for descriptors.
The test version of OFW that I gave saadia reports 31K for each buffer,
leaving a total of 0x1000 bytes for descriptors. I used 31K instead of
62K because I wasn't sure whether Linux was assuming double-buffering and
thus allocating 4 buffers (2 playback, 2 capture). I now suspect that 62K
for each buffer might be better, under the assumption that the total
buffer space is carved into more than two buffers per direction.
--
Ticket URL: <http://dev.laptop.org/ticket/12400#comment:8>
One Laptop Per Child <http://laptop.org/>
OLPC bug tracking system
More information about the Bugs
mailing list