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ARM asm LCD and ATA driver functions: Don't save r12 as it is a scratch reg. Saves a bit of stack and execution time.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21795 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Jens Arnold 2009-07-11 23:43:44 +00:00
parent fa59ed6ae7
commit 47d4c4739b
12 changed files with 256 additions and 261 deletions
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16
firmware/target/arm/as3525/sansa-clip/lcd-as-clip.S
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@ -39,15 +39,15 @@
* r3/r4 - current block of phases
* r5/r6 - current block of values
* r7 - lcd data accumulator
* r8 - phase signs mask
* r12 - phase signs mask
* lr - lcd bridge address
*/
lcd_grey_data:
stmfd sp!, {r4-r8, lr}
mov r8, #0x80
orr r8, r8, r8, lsl #8
orr r8, r8, r8, lsl #16
stmfd sp!, {r4-r7, lr}
mov r12, #0x80
orr r12, r12, r12, lsl #8
orr r12, r12, r12, lsl #16
ldr lr, =GPIOA_BASE
mov r3, #(1<<5)
@ -70,7 +70,7 @@ lcd_grey_data:
orrne r7, r7, #0x2000
tst r3, #0x80000000
orrne r7, r7, #0x1000
bic r3, r3, r8
bic r3, r3, r12
add r3, r3, r5
/* set bits 3..0 */
@ -82,7 +82,7 @@ lcd_grey_data:
orrne r7, r7, #0x02
tst r4, #0x80000000
orrne r7, r7, #0x01
bic r4, r4, r8
bic r4, r4, r12
add r4, r4, r6
stmia r1!, {r3-r4}
@ -102,5 +102,5 @@ lcd_grey_data:
ands r5, r5, #(1<<10) @ wait until push fifo empties
beq 1b
ldmfd sp!, {r4-r8, pc}
ldmfd sp!, {r4-r7, pc}
.size lcd_grey_data,.-lcd_grey_data