From 7d21e5ab32ef24724c201b5ffc4df3a2637966e7 Mon Sep 17 00:00:00 2001 From: Andree Buschmann Date: Mon, 10 May 2010 20:35:57 +0000 Subject: No need to use alternating registers for dual register read/write sequence. Correct comment. git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25939 a1c6a512-1295-4272-9138-f99709370657 --- firmware/target/arm/ipod/video/lcd-as-video.S | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/firmware/target/arm/ipod/video/lcd-as-video.S b/firmware/target/arm/ipod/video/lcd-as-video.S index 21a04a6529..fa88dbc940 100644 --- a/firmware/target/arm/ipod/video/lcd-as-video.S +++ b/firmware/target/arm/ipod/video/lcd-as-video.S @@ -26,8 +26,7 @@ * int pixelcount); * * Writes pixelcount pixels from src-pointer (lcd_framebuffer) to BCM dataport. - * Use the sequence ld 2, wr 2, ld 2, wr 2 with alternating registers for best - * performance. + * Use the sequence 2:2:2:2 (2 = read/write 2 regs) for best performance. */ .align 2 .global lcd_write_data @@ -41,12 +40,12 @@ lcd_write_data: /* r1 = pixel count, must be even */ .loop16: ldmgeia r0!, {r2-r3} stmgeia lr, {r2-r3} - ldmgeia r0!, {r4, r12} - stmgeia lr, {r4, r12} ldmgeia r0!, {r2-r3} stmgeia lr, {r2-r3} - ldmgeia r0!, {r4, r12} - stmgeia lr, {r4, r12} + ldmgeia r0!, {r2-r3} + stmgeia lr, {r2-r3} + ldmgeia r0!, {r2-r3} + stmgeia lr, {r2-r3} subges r1, r1, #16 bge .loop16 -- cgit v1.2.3