[openfirmware] [commit] r2663 - cpu/arm/olpc/1.75

[repository service]

Author: quozl
Date: Tue Nov  1 09:04:25 2011
New Revision: 2663
URL: http://tracker.coreboot.org/trac/openfirmware/changeset/2663

Log:
OLPC XO-1.75 - use read multiple for acceleration vectors, reducing read time (when data is ready) from 1ms to 600us at 400kHz bus speed.

Modified:
   cpu/arm/olpc/1.75/accelerometer.fth

Modified: cpu/arm/olpc/1.75/accelerometer.fth
==============================================================================
--- cpu/arm/olpc/1.75/accelerometer.fth	Tue Nov  1 09:01:36 2011	(r2662)
+++ cpu/arm/olpc/1.75/accelerometer.fth	Tue Nov  1 09:04:25 2011	(r2663)
@@ -16,9 +16,13 @@
 : wext  ( b -- n )  dup h# 8000 and  if  h# ffff0000 or  then  ;
 : acceleration@  ( -- x y z )
    begin  h# 27 acc-reg@  h# 08 and  until  \ wait for data available
-   h# 28 acc-reg@ h# 29 acc-reg@ bwjoin wext 5 >>a
-   h# 2a acc-reg@ h# 2b acc-reg@ bwjoin wext 5 >>a
-   h# 2c acc-reg@ h# 2d acc-reg@ bwjoin wext 5 >>a
+   h# 0a8 1 6 " smbus-out-in" $call-parent ( xl xh yl yh zl zh )
+   bwjoin wext 5 >>a     ( xl xh yl yh z )
+   >r                    ( xl xh yl yh     r: z )
+   bwjoin wext 5 >>a     ( xl xh y         r: z )
+   >r                    ( xl xh           r: z y )
+   bwjoin wext 5 >>a     ( x               r: z y )
+   r> r> ( x y z )
 ;
 
 : t+  ( x1 y1 z1 x2 y2 z2 -- x3 y3 z3 )