Changeset 3645


Ignore:
Timestamp:
Apr 18, 2013, 5:44:59 AM (19 months ago)
Author:
quozl
Message:

OLPC XO-4 - add device-tree entries in /pcm to describe allocation of audio SRAM, used by kernel only. Open Firmware uses other allocations. #12400

Location:
cpu/arm
Files:
2 edited

Legend:

Unmodified
Added
Removed
  • cpu/arm/mmp3/soc-config.fth

    r3218 r3645  
    99\ No need to map audio-sram separately; it fits in the SRAM area 
    1010 
     11d# 4096  constant /audio-sram-dma  \ space for DMA descriptors 
     12d# 2048  constant /audio-sram-mps  \ maximum period size 
     13/audio-sram /audio-sram-dma -  2 /  constant /audio-sram-pcm  \ buffers 
     14 
    1115h# 0005.0000 constant /sram          \ Size of SRAM 
  • cpu/arm/olpc/sound.fth

    r3623 r3645  
    8282   " marvell,mmp-pcm-audio" +compatible   \ snd_soc_dai_link.cpu_dai_of_node 
    8383 
     84[ifdef] mmp3 
     85   \ Our asram node (below) declares that /audio-sram bytes of SRAM 
     86   \ are assigned to the audio function.  We divide that here, roughly 
     87   \ half to playback and half to recording. 
     88 
     89   \ Even though we choose big buffers, we do leave a little bit of 
     90   \ free space for the DMA engine which also needs to use a bit of 
     91   \ the SRAM area for DMA descriptors. Therefore we choose 62kb for 
     92   \ each buffer, leaving 4kb available for DMA descriptors. 
     93 
     94   \ For the max period size, we don't have any justification other 
     95   \ than 2048 is the value we've been using all along. 
     96 
     97   /audio-sram-pcm encode-int 
     98   /audio-sram-mps encode-int encode+ 
     99   /audio-sram-pcm encode-int encode+ 
     100   /audio-sram-mps encode-int encode+ 
     101   " marvell,buffer-sizes" property 
     102[then] 
    84103finish-device 
    85104 
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