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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2007 by Michael Sevakis
*
* ARM code for memory framebuffer LCDs
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "config.h"
#include "cpu.h"
/****************************************************************************
* void lcd_copy_buffer_rect(fb_data *dst, fb_data *src, int width,
* int height);
*/
.section .icode, "ax", %progbits
.align 2
.global lcd_copy_buffer_rect
.type lcd_copy_buffer_rect, %function
@ r0 = dst
@ r1 = src
@ r2 = width
@ r3 = height
lcd_copy_buffer_rect: @
stmfd sp!, { r4-r12, lr } @ save non-scratch regs
mov r5, r2 @ r5 = cached width
rsb r4, r2, #LCD_WIDTH @ r4 = LCD_WIDTH - width
10: @ copy line @
subs r2, r5, #1 @ r2 = width - 1
beq 40f @ finish line @ one halfword? skip to trailing copy
tst r0, #2 @ word aligned?
beq 20f @ rem copy @ yes? skip to word copy
ldrh r6, [r1], #2 @ copy leading halfword
subs r2, r2, #1 @
strh r6, [r0], #2 @
ble 40f @ finish line @ next line if lt or finish
@ trailing halfword if eq
20: @ rem copy @
add r14, r2, #1 @ get remaining width mod 16 after word
@ align (rw)
and r14, r14, #0xe @ r14 = 0 (16), 2, 4, 6, 8, 10, 12, 14
add pc, pc, r14, lsl #3 @ branch to 32-byte align
nop @
b 30f @ rw % 16 = 0 or 1? use octword loop
nop @
nop @
nop @
ldr r6, [r1], #4 @ rw % 16 = 2 or 3
subs r2, r2, #2 @
str r6, [r0], #4 @
b 25f @ copy up done @
ldmia r1!, { r6-r7 } @ rw % 16 = 4 or 5
subs r2, r2, #4 @
stmia r0!, { r6-r7 } @
b 25f @ copy up done @
ldmia r1!, { r6-r8 } @ rw % 16 = 6 or 7
subs r2, r2, #6 @
stmia r0!, { r6-r8 } @
b 25f @ copy up done @
ldmia r1!, { r6-r9 } @ rw % 16 = 8 or 9
subs r2, r2, #8 @
stmia r0!, { r6-r9 } @
b 25f @ copy up done @
ldmia r1!, { r6-r10 } @ rw % 16 = 10 or 11
subs r2, r2, #10 @
stmia r0!, { r6-r10 } @
b 25f @ copy up done @
ldmia r1!, { r6-r11 } @ rw % 16 = 12 or 13
subs r2, r2, #12 @
stmia r0!, { r6-r11 } @
b 25f @ copy up done @
ldmia r1!, { r6-r12 } @ rw % 16 = 14 or 15
subs r2, r2, #14 @
stmia r0!, { r6-r12 } @
25: @ copy up done @
ble 40f @ finish line @ no 32-byte segments remaining?
30: @ octword loop @ copy 16 pixels per loop
ldmia r1!, { r6-r12, r14 } @
subs r2, r2, #16 @
stmia r0!, { r6-r12, r14 } @
bgt 30b @ octword loop @
40: @ finish line @
ldreqh r6, [r1], #2 @ finish last halfword if eq ...
add r1, r1, r4, lsl #1 @
streqh r6, [r0], #2 @ ...
add r0, r0, r4, lsl #1 @
subs r3, r3, #1 @ next line
bgt 10b @ copy line @
ldmfd sp!, { r4-r12, pc } @ restore regs and return
.ltorg @ dump constant pool
.size lcd_copy_buffer_rect, .-lcd_copy_buffer_rect
/****************************************************************************
* void lcd_write_yuv_420_lines(fb_data *dst,
* unsigned char const * const src[3],
* int width,
* int stride);
*
* |R| |1.000000 -0.000001 1.402000| |Y'|
* |G| = |1.000000 -0.334136 -0.714136| |Pb|
* |B| |1.000000 1.772000 0.000000| |Pr|
* Scaled, normalized, rounded and tweaked to yield RGB 565:
* |R| |74 0 101| |Y' - 16| >> 9
* |G| = |74 -24 -51| |Cb - 128| >> 8
* |B| |74 128 0| |Cr - 128| >> 9
*
* Write four RGB565 pixels in the following order on each loop:
* 1 3 + > down
* 2 4 \/ left
*/
.section .icode, "ax", %progbits
.align 2
.global lcd_write_yuv420_lines
.type lcd_write_yuv420_lines, %function
lcd_write_yuv420_lines:
@ r0 = dst
@ r1 = yuv_src
@ r2 = width
@ r3 = stride
stmfd sp!, { r4-r12 } @ save non-scratch
ldmia r1, { r4, r5, r6 } @ r4 = yuv_src[0] = Y'_p
@ r5 = yuv_src[1] = Cb_p
@ r6 = yuv_src[2] = Cr_p
@ r1 = scratch
sub r3, r3, #1 @
10: @ loop line @
ldrb r7, [r4], #1 @ r7 = *Y'_p++;
ldrb r8, [r5], #1 @ r8 = *Cb_p++;
ldrb r9, [r6], #1 @ r9 = *Cr_p++;
@
sub r7, r7, #16 @ r7 = Y = (Y' - 16)*74
add r12, r7, r7, asl #2 @ actually (Y' - 16)*37 and shift right
add r7, r12, r7, asl #5 @ by one less when adding - same for all
@
sub r8, r8, #128 @ Cb -= 128
sub r9, r9, #128 @ Cr -= 128
@
add r10, r9, r9, asl #1 @ r10 = Cr*51 + Cb*24
add r10, r10, r10, asl #4 @
add r10, r10, r8, asl #3 @
add r10, r10, r8, asl #4 @
@
add r11, r9, r9, asl #2 @ r9 = Cr*101
add r11, r11, r9, asl #5 @
add r9, r11, r9, asl #6 @
@
add r8, r8, #2 @ r8 = bu = (Cb*128 + 128) >> 8
mov r8, r8, asr #2 @
add r9, r9, #256 @ r9 = rv = (r9 + 256) >> 9
mov r9, r9, asr #9 @
rsb r10, r10, #128 @ r10 = guv = (-r10 + 128) >> 8
mov r10, r10, asr #8 @
@ compute R, G, and B
add r1, r8, r7, asr #8 @ r1 = b = (Y >> 9) + bu
add r11, r9, r7, asr #8 @ r11 = r = (Y >> 9) + rv
add r7, r10, r7, asr #7 @ r7 = g = (Y >> 8) + guv
@
orr r12, r1, r11 @ check if clamping is needed...
orr r12, r12, r7, asr #1 @ ...at all
cmp r12, #31 @
bls 15f @ no clamp @
cmp r1, #31 @ clamp b
mvnhi r1, r1, asr #31 @
andhi r1, r1, #31 @
cmp r11, #31 @ clamp r
mvnhi r11, r11, asr #31 @
andhi r11, r11, #31 @
cmp r7, #63 @ clamp g
mvnhi r7, r7, asr #31 @
andhi r7, r7, #63 @
15: @ no clamp @
@
ldrb r12, [r4, r3] @ r12 = Y' = *(Y'_p + stride)
@
orr r1, r1, r7, lsl #5 @ r4 |= (g << 5)
orr r1, r1, r11, lsl #11 @ r4 = b | (r << 11)
#if LCD_WIDTH >= LCD_HEIGHT
strh r1, [r0] @
#elif LCD_WIDTH < 256
strh r1, [r0], #LCD_WIDTH @ store pixel
#else
strh r1, [r0] @
#endif
@
sub r7, r12, #16 @ r7 = Y = (Y' - 16)*74
add r12, r7, r7, asl #2 @
add r7, r12, r7, asl #5 @
@ compute R, G, and B
add r1, r8, r7, asr #8 @ r1 = b = (Y >> 9) + bu
add r11, r9, r7, asr #8 @ r11 = r = (Y >> 9) + rv
add r7, r10, r7, asr #7 @ r7 = g = (Y >> 8) + guv
@
orr r12, r1, r11 @ check if clamping is needed...
orr r12, r12, r7, asr #1 @ ...at all
cmp r12, #31 @
bls 15f @ no clamp @
cmp r1, #31 @ clamp b
mvnhi r1, r1, asr #31 @
andhi r1, r1, #31 @
cmp r11, #31 @ clamp r
mvnhi r11, r11, asr #31 @
andhi r11, r11, #31 @
cmp r7, #63 @ clamp g
mvnhi r7, r7, asr #31 @
andhi r7, r7, #63 @
15: @ no clamp @
@
ldrb r12, [r4], #1 @ r12 = Y' = *(Y'_p++)
@
orr r1, r1, r11, lsl #11 @ r1 = b | (r << 11)
orr r1, r1, r7, lsl #5 @ r1 |= (g << 5)
#if LCD_WIDTH >= LCD_HEIGHT
add r0, r0, #2*LCD_WIDTH @
strh r1, [r0] @ store pixel
sub r0, r0, #2*LCD_WIDTH @
#elif LCD_WIDTH < 256
strh r1, [r0, #-LCD_WIDTH-2] @ store pixel
#else
strh r1, [r0, #-2] @
add r0, r0, #LCD_WIDTH @
#endif
@
sub r7, r12, #16 @ r7 = Y = (Y' - 16)*74
add r12, r7, r7, asl #2 @
add r7, r12, r7, asl #5 @
@ compute R, G, and B
add r1, r8, r7, asr #8 @ r1 = b = (Y >> 9) + bu
add r11, r9, r7, asr #8 @ r11 = r = (Y >> 9) + rv
add r7, r10, r7, asr #7 @ r7 = g = (Y >> 8) + guv
@
orr r12, r1, r11 @ check if clamping is needed...
orr r12, r12, r7, asr #1 @ ...at all
cmp r12, #31 @
bls 15f @ no clamp @
cmp r1, #31 @ clamp b
mvnhi r1, r1, asr #31 @
andhi r1, r1, #31 @
cmp r11, #31 @ clamp r
mvnhi r11, r11, asr #31 @
andhi r11, r11, #31 @
cmp r7, #63 @ clamp g
mvnhi r7, r7, asr #31 @
andhi r7, r7, #63 @
15: @ no clamp @
@
ldrb r12, [r4, r3] @ r12 = Y' = *(Y'_p + stride)
@
orr r1, r1, r7, lsl #5 @ r1 = b | (g << 5)
orr r1, r1, r11, lsl #11 @ r1 |= (r << 11)
#if LCD_WIDTH >= LCD_HEIGHT
strh r1, [r0, #2]
#elif LCD_WIDTH < 256
strh r1, [r0, #LCD_WIDTH]! @ store pixel
#else
strh r1, [r0] @
#endif
@
sub r7, r12, #16 @ r7 = Y = (Y' - 16)*74
add r12, r7, r7, asl #2 @
add r7, r12, r7, asl #5 @
@ compute R, G, and B
add r1, r8, r7, asr #8 @ r1 = b = (Y >> 9) + bu
add r11, r9, r7, asr #8 @ r11 = r = (Y >> 9) + rv
add r7, r10, r7, asr #7 @ r7 = g = (Y >> 8) + guv
@
orr r12, r1, r11 @ check if clamping is needed...
orr r12, r12, r7, asr #1 @ ...at all
cmp r12, #31 @
bls 15f @ no clamp @
cmp r1, #31 @ clamp b
mvnhi r1, r1, asr #31 @
andhi r1, r1, #31 @
cmp r11, #31 @ clamp r
mvnhi r11, r11, asr #31 @
andhi r11, r11, #31 @
cmp r7, #63 @ clamp g
mvnhi r7, r7, asr #31 @
andhi r7, r7, #63 @
15: @ no clamp @
@
orr r12, r1, r11, lsl #11 @ r12 = b | (r << 11)
orr r12, r12, r7, lsl #5 @ r12 |= (g << 5)
#if LCD_WIDTH >= LCD_HEIGHT
add r0, r0, #2*LCD_WIDTH
strh r12, [r0, #2]
#if LCD_WIDTH <= 512
sub r0, r0, #(2*LCD_WIDTH)-4
#else
sub r0, r0, #(2*LCD_WIDTH)
add r0, r0, #4
#endif
#else
strh r12, [r0, #-2] @ store pixel
#if LCD_WIDTH < 256
add r0, r0, #2*LCD_WIDTH @
#else
add r0, r0, #LCD_WIDTH @
#endif
#endif
@
subs r2, r2, #2 @ subtract block from width
bgt 10b @ loop line @
@
ldmfd sp!, { r4-r12 } @ restore registers and return
bx lr @
.ltorg @ dump constant pool
.size lcd_write_yuv420_lines, .-lcd_write_yuv420_lines
/****************************************************************************
* void lcd_write_yuv_420_lines_odither(fb_data *dst,
* unsigned char const * const src[3],
* int width,
* int stride,
* int x_screen,
* int y_screen);
*
* |R| |1.000000 -0.000001 1.402000| |Y'|
* |G| = |1.000000 -0.334136 -0.714136| |Pb|
* |B| |1.000000 1.772000 0.000000| |Pr|
* Red scaled at twice g & b but at same precision to place it in correct
* bit position after multiply and leave instruction count lower.
* |R| |258 0 408| |Y' - 16|
* |G| = |149 -49 -104| |Cb - 128|
* |B| |149 258 0| |Cr - 128|
*
* Write four RGB565 pixels in the following order on each loop:
* 1 3 + > down
* 2 4 \/ left
*
* Kernel pattern (raw|rotated|use order):
* 5 3 4 2 2 6 3 7 row0 row2 > down
* 1 7 0 6 | 4 0 5 1 | 2 4 6 0 3 5 7 1 col0 left
* 4 2 5 3 | 3 7 2 6 | 3 5 7 1 2 4 6 0 col2 \/
* 0 6 1 7 5 1 4 0
*/
.section .icode, "ax", %progbits
.align 2
.global lcd_write_yuv420_lines_odither
.type lcd_write_yuv420_lines_odither, %function
lcd_write_yuv420_lines_odither:
@ r0 = dst
@ r1 = yuv_src
@ r2 = width
@ r3 = stride
@ [sp] = x_screen
@ [sp+4] = y_screen
stmfd sp!, { r4-r12, lr } @ save non-scratch
ldmia r1, { r4, r5, r6 } @ r4 = yuv_src[0] = Y'_p
@ r5 = yuv_src[1] = Cb_p
@ r6 = yuv_src[2] = Cr_p
@
sub r3, r3, #1 @
add r1, sp, #40 @ Line up pattern and kernel quadrant
ldmia r1, { r12, r14 } @
eor r14, r14, r12 @
and r14, r14, #0x2 @
mov r14, r14, lsl #6 @ 0x00 or 0x80
10: @ loop line @
@
ldrb r7, [r4], #1 @ r7 = *Y'_p++;
ldrb r8, [r5], #1 @ r8 = *Cb_p++;
ldrb r9, [r6], #1 @ r9 = *Cr_p++;
@
eor r14, r14, #0x80 @ flip pattern quadrant
@
sub r7, r7, #16 @ r7 = Y = (Y' - 16)*149
add r12, r7, r7, asl #2 @
add r12, r12, r12, asl #4 @
add r7, r12, r7, asl #6 @
@
sub r8, r8, #128 @ Cb -= 128
sub r9, r9, #128 @ Cr -= 128
@
add r10, r8, r8, asl #4 @ r10 = guv = Cr*104 + Cb*49
add r10, r10, r8, asl #5 @
add r10, r10, r9, asl #3 @
add r10, r10, r9, asl #5 @
add r10, r10, r9, asl #6 @
@
mov r8, r8, asl #1 @ r8 = bu = Cb*258
add r8, r8, r8, asl #7 @
@
add r9, r9, r9, asl #1 @ r9 = rv = Cr*408
add r9, r9, r9, asl #4 @
mov r9, r9, asl #3 @
@
@ compute R, G, and B
add r1, r8, r7 @ r1 = b' = Y + bu
add r11, r9, r7, asl #1 @ r11 = r' = Y*2 + rv
rsb r7, r10, r7 @ r7 = g' = Y + guv
@
@ r8 = bu, r9 = rv, r10 = guv
@
sub r12, r1, r1, lsr #5 @ r1 = 31/32*b + b/256
add r1, r12, r1, lsr #8 @
@
sub r12, r11, r11, lsr #5 @ r11 = 31/32*r + r/256
add r11, r12, r11, lsr #8 @
@
sub r12, r7, r7, lsr #6 @ r7 = 63/64*g + g/256
add r7, r12, r7, lsr #8 @
@
add r12, r14, #0x100 @
@
add r1, r1, r12 @ b = r1 + delta
add r11, r11, r12, lsl #1 @ r = r11 + delta*2
add r7, r7, r12, lsr #1 @ g = r7 + delta/2
@
orr r12, r1, r11, asr #1 @ check if clamping is needed...
orr r12, r12, r7 @ ...at all
movs r12, r12, asr #15 @
beq 15f @ no clamp @
movs r12, r1, asr #15 @ clamp b
mvnne r1, r12, lsr #15 @
andne r1, r1, #0x7c00 @ mask b only if clamped
movs r12, r11, asr #16 @ clamp r
mvnne r11, r12, lsr #16 @
movs r12, r7, asr #15 @ clamp g
mvnne r7, r12, lsr #15 @
15: @ no clamp @
@
ldrb r12, [r4, r3] @ r12 = Y' = *(Y'_p + stride)
@
and r11, r11, #0xf800 @ pack pixel
and r7, r7, #0x7e00 @ r1 = pixel = (r & 0xf800) |
orr r11, r11, r7, lsr #4 @ ((g & 0x7e00) >> 4) |
orr r1, r11, r1, lsr #10 @ (b >> 10)
@
#if LCD_WIDTH >= LCD_HEIGHT
strh r1, [r0] @
#elif LCD_WIDTH < 256
strh r1, [r0], #LCD_WIDTH @ store pixel
#else
strh r1, [r0] @
#endif
@
sub r7, r12, #16 @ r7 = Y = (Y' - 16)*149
add r12, r7, r7, asl #2 @
add r12, r12, r12, asl #4 @
add r7, r12, r7, asl #6 @
@ compute R, G, and B
add r1, r8, r7 @ r1 = b' = Y + bu
add r11, r9, r7, asl #1 @ r11 = r' = Y*2 + rv
rsb r7, r10, r7 @ r7 = g' = Y + guv
@
sub r12, r1, r1, lsr #5 @ r1 = 31/32*b' + b'/256
add r1, r12, r1, lsr #8 @
@
sub r12, r11, r11, lsr #5 @ r11 = 31/32*r' + r'/256
add r11, r12, r11, lsr #8 @
@
sub r12, r7, r7, lsr #6 @ r7 = 63/64*g' + g'/256
add r7, r12, r7, lsr #8 @
@
add r12, r14, #0x200 @
@
add r1, r1, r12 @ b = r1 + delta
add r11, r11, r12, lsl #1 @ r = r11 + delta*2
add r7, r7, r12, lsr #1 @ g = r7 + delta/2
@
orr r12, r1, r11, asr #1 @ check if clamping is needed...
orr r12, r12, r7 @ ...at all
movs r12, r12, asr #15 @
beq 15f @ no clamp @
movs r12, r1, asr #15 @ clamp b
mvnne r1, r12, lsr #15 @
andne r1, r1, #0x7c00 @ mask b only if clamped
movs r12, r11, asr #16 @ clamp r
mvnne r11, r12, lsr #16 @
movs r12, r7, asr #15 @ clamp g
mvnne r7, r12, lsr #15 @
15: @ no clamp @
@
ldrb r12, [r4], #1 @ r12 = Y' = *(Y'_p++)
@
and r11, r11, #0xf800 @ pack pixel
and r7, r7, #0x7e00 @ r1 = pixel = (r & 0xf800) |
orr r11, r11, r7, lsr #4 @ ((g & 0x7e00) >> 4) |
orr r1, r11, r1, lsr #10 @ (b >> 10)
@
#if LCD_WIDTH >= LCD_HEIGHT
add r0, r0, #2*LCD_WIDTH @
strh r1, [r0] @ store pixel
sub r0, r0, #2*LCD_WIDTH @
#elif LCD_WIDTH < 256
strh r1, [r0, #-LCD_WIDTH-2] @ store pixel
#else
strh r1, [r0, #-2] @ store pixel
add r0, r0, #LCD_WIDTH @
#endif
@
sub r7, r12, #16 @ r7 = Y = (Y' - 16)*149
add r12, r7, r7, asl #2 @
add r12, r12, r12, asl #4 @
add r7, r12, r7, asl #6 @
@ compute R, G, and B
add r1, r8, r7 @ r1 = b' = Y + bu
add r11, r9, r7, asl #1 @ r11 = r' = Y*2 + rv
rsb r7, r10, r7 @ r7 = g' = Y + guv
@
@ r8 = bu, r9 = rv, r10 = guv
@
sub r12, r1, r1, lsr #5 @ r1 = 31/32*b' + b'/256
add r1, r12, r1, lsr #8 @
@
sub r12, r11, r11, lsr #5 @ r11 = 31/32*r' + r'/256
add r11, r12, r11, lsr #8 @
@
sub r12, r7, r7, lsr #6 @ r7 = 63/64*g' + g'/256
add r7, r12, r7, lsr #8 @
@
add r12, r14, #0x300 @
@
add r1, r1, r12 @ b = r1 + delta
add r11, r11, r12, lsl #1 @ r = r11 + delta*2
add r7, r7, r12, lsr #1 @ g = r7 + delta/2
@
orr r12, r1, r11, asr #1 @ check if clamping is needed...
orr r12, r12, r7 @ ...at all
movs r12, r12, asr #15 @
beq 15f @ no clamp @
movs r12, r1, asr #15 @ clamp b
mvnne r1, r12, lsr #15 @
andne r1, r1, #0x7c00 @ mask b only if clamped
movs r12, r11, asr #16 @ clamp r
mvnne r11, r12, lsr #16 @
movs r12, r7, asr #15 @ clamp g
mvnne r7, r12, lsr #15 @
15: @ no clamp @
@
ldrb r12, [r4, r3] @ r12 = Y' = *(Y'_p + stride)
@
and r11, r11, #0xf800 @ pack pixel
and r7, r7, #0x7e00 @ r1 = pixel = (r & 0xf800) |
orr r11, r11, r7, lsr #4 @ ((g & 0x7e00) >> 4) |
orr r1, r11, r1, lsr #10 @ (b >> 10)
@
#if LCD_WIDTH >= LCD_HEIGHT
strh r1, [r0, #2]
#elif LCD_WIDTH < 256
strh r1, [r0, #LCD_WIDTH]! @ store pixel
#else
strh r1, [r0] @
#endif
sub r7, r12, #16 @ r7 = Y = (Y' - 16)*149
add r12, r7, r7, asl #2 @
add r12, r12, r12, asl #4 @
add r7, r12, r7, asl #6 @
@ compute R, G, and B
add r1, r8, r7 @ r1 = b' = Y + bu
add r11, r9, r7, asl #1 @ r11 = r' = Y*2 + rv
rsb r7, r10, r7 @ r7 = g' = Y + guv
@
sub r12, r1, r1, lsr #5 @ r1 = 31/32*b + b/256
add r1, r12, r1, lsr #8 @
@
sub r12, r11, r11, lsr #5 @ r11 = 31/32*r + r/256
add r11, r12, r11, lsr #8 @
@
sub r12, r7, r7, lsr #6 @ r7 = 63/64*g + g/256
add r7, r12, r7, lsr #8 @
@
@ This element is zero - use r14 @
@
add r1, r1, r14 @ b = r1 + delta
add r11, r11, r14, lsl #1 @ r = r11 + delta*2
add r7, r7, r14, lsr #1 @ g = r7 + delta/2
@
orr r12, r1, r11, asr #1 @ check if clamping is needed...
orr r12, r12, r7 @ ...at all
movs r12, r12, asr #15 @
beq 15f @ no clamp @
movs r12, r1, asr #15 @ clamp b
mvnne r1, r12, lsr #15 @
andne r1, r1, #0x7c00 @ mask b only if clamped
movs r12, r11, asr #16 @ clamp r
mvnne r11, r12, lsr #16 @
movs r12, r7, asr #15 @ clamp g
mvnne r7, r12, lsr #15 @
15: @ no clamp @
@
and r11, r11, #0xf800 @ pack pixel
and r7, r7, #0x7e00 @ r1 = pixel = (r & 0xf800) |
orr r11, r11, r7, lsr #4 @ ((g & 0x7e00) >> 4) |
orr r1, r11, r1, lsr #10 @ (b >> 10)
@
#if LCD_WIDTH >= LCD_HEIGHT
add r0, r0, #2*LCD_WIDTH
strh r1, [r0, #2] @ store pixel
#if LCD_WIDTH <= 512
sub r0, r0, #(2*LCD_WIDTH)-4
#else
sub r0, r0, #(2*LCD_WIDTH)
add r0, r0, #4
#endif
#else
strh r1, [r0, #-2] @ store pixel
#if LCD_WIDTH < 256
add r0, r0, #2*LCD_WIDTH @
#else
add r0, r0, #LCD_WIDTH @
#endif
#endif
@
subs r2, r2, #2 @ subtract block from width
bgt 10b @ loop line @
@
ldmfd sp!, { r4-r12, pc } @ restore registers and return
.ltorg @ dump constant pool
.size lcd_write_yuv420_lines_odither, .-lcd_write_yuv420_lines_odither
|
