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|
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2007 by Jens Arnold
* Heavily based on lcd-as-memframe.c by Michael Sevakis
* Adapted for Sansa Fuze/e200v2 by Rafaël Carré
*
* 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"
#define DBOP_BUSY (1<<10)
/****************************************************************************
* void lcd_write_yuv420_lines(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 = yuv_src
@ r1 = width
@ r2 = stride
stmfd sp!, { r4-r11, lr } @ save non-scratch
mov r3, #0xC8000000 @
orr r3, r3, #0x120000 @ r3 = DBOP_BASE
ldmia r0, { r4, r5, r6 } @ r4 = yuv_src[0] = Y'_p
@ r5 = yuv_src[1] = Cb_p
@ r6 = yuv_src[2] = Cr_p
@ r0 = scratch
ldr r12, [r3, #8] @
sub r2, r2, #1 @ stride -= 1
orr r12, r12, #3<<13 @ DBOP_CTRL |= (1<<13|1<<14) (32bit mode)
#ifdef SANSA_FUZEV2
bic r12, r12, #1<<13 @ DBOP_CTRL &= ~(1<<13),still 32bit mode
#endif
str r12, [r3, #8] @
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 lr, r9, r9, asl #2 @ r9 = Cr*101
add lr, lr, r9, asl #5 @
add r9, lr, 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 r0, r8, r7, asr #8 @ r0 = b = (Y >> 9) + bu
add lr, r9, r7, asr #8 @ lr = r = (Y >> 9) + rv
add r7, r10, r7, asr #7 @ r7 = g = (Y >> 8) + guv
@
orr r12, r0, lr @ check if clamping is needed...
orr r12, r12, r7, asr #1 @ ...at all
cmp r12, #31 @
bls 15f @ no clamp @
cmp r0, #31 @ clamp b
mvnhi r0, r0, asr #31 @
andhi r0, r0, #31 @
cmp lr, #31 @ clamp r
mvnhi lr, lr, asr #31 @
andhi lr, lr, #31 @
cmp r7, #63 @ clamp g
mvnhi r7, r7, asr #31 @
andhi r7, r7, #63 @
15: @ no clamp @
@
ldrb r12, [r4, r2] @ r12 = Y' = *(Y'_p + stride)
@
orr r0, r0, lr, lsl #11 @ r0 = (r << 11) | b
orr r11, r0, r7, lsl #5 @ r11 = (r << 11) | (g << 5) | b
orr r11, r0, r7, lsl #5 @ r11 = (r << 11) | (g << 5) | b
#ifdef SANSA_FUZEV2
mov r0, r11, lsr #8 @
bic r11, r11, #0xff00 @
orr r11, r0, r11, lsl #8 @ swap bytes
#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 r0, r8, r7, asr #8 @ r0 = b = (Y >> 9) + bu
add lr, r9, r7, asr #8 @ lr = r = (Y >> 9) + rv
add r7, r10, r7, asr #7 @ r7 = g = (Y >> 8) + guv
@
orr r12, r0, lr @ check if clamping is needed...
orr r12, r12, r7, asr #1 @ ...at all
cmp r12, #31 @
bls 15f @ no clamp @
cmp r0, #31 @ clamp b
mvnhi r0, r0, asr #31 @
andhi r0, r0, #31 @
cmp lr, #31 @ clamp r
mvnhi lr, lr, asr #31 @
andhi lr, lr, #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 r0, r0, lr, lsl #11 @ r0 = (r << 11) | b
orr r0, r0, r7, lsl #5 @ r0 = (r << 11) | (g << 5) | b
#ifdef SANSA_FUZEV2
mov r7, r0, lsr #8 @
bic r7, r7, #0xff00 @
orr r0, r7, r0, lsl #8 @ swap bytes
#endif
orr r0, r11, r0, lsl#16 @ pack with 2nd pixel
str r0, [r3, #0x10] @ write pixel
@
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 r0, r8, r7, asr #8 @ r0 = b = (Y >> 9) + bu
add lr, r9, r7, asr #8 @ lr = r = (Y >> 9) + rv
add r7, r10, r7, asr #7 @ r7 = g = (Y >> 8) + guv
@
orr r12, r0, lr @ check if clamping is needed...
orr r12, r12, r7, asr #1 @ ...at all
cmp r12, #31 @
bls 15f @ no clamp @
cmp r0, #31 @ clamp b
mvnhi r0, r0, asr #31 @
andhi r0, r0, #31 @
cmp lr, #31 @ clamp r
mvnhi lr, lr, asr #31 @
andhi lr, lr, #31 @
cmp r7, #63 @ clamp g
mvnhi r7, r7, asr #31 @
andhi r7, r7, #63 @
15: @ no clamp @
@
ldrb r12, [r4, r2] @ r12 = Y' = *(Y'_p + stride)
@
@
orr r0, r0, lr, lsl #11 @ r0 = (r << 11) | b
orr r11, r0, r7, lsl #5 @ r0 = (r << 11) | (g << 5) | b
#ifdef SANSA_FUZEV2
mov r0, r11, lsr #8 @
bic r11, r11, #0xff00 @
orr r11, r0, r11, lsl #8 @ swap byte
#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 r0, r8, r7, asr #8 @ r0 = b = (Y >> 9) + bu
add lr, r9, r7, asr #8 @ lr = r = (Y >> 9) + rv
add r7, r10, r7, asr #7 @ r7 = g = (Y >> 8) + guv
@
orr r12, r0, lr @ check if clamping is needed...
orr r12, r12, r7, asr #1 @ ...at all
cmp r12, #31 @
bls 15f @ no clamp @
cmp r0, #31 @ clamp b
mvnhi r0, r0, asr #31 @
andhi r0, r0, #31 @
cmp lr, #31 @ clamp r
mvnhi lr, lr, asr #31 @
andhi lr, lr, #31 @
cmp r7, #63 @ clamp g
mvnhi r7, r7, asr #31 @
andhi r7, r7, #63 @
15: @ no clamp @
@
orr r0, r0, lr, lsl #11 @ r0 = (r << 11) | b
orr r0, r0, r7, lsl #5 @ r0 = (r << 11) | (g << 5) | b
#ifdef SANSA_FUZEV2
mov r7, r0, lsr #8 @
bic r7, r7, #0xff00 @
orr r0, r7, r0, lsl #8 @ swap bytes
#endif
orr r0, r11, r0, lsl#16 @ pack with 2nd pixel
str r0, [r3, #0x10] @ write pixel
@
subs r1, r1, #2 @ subtract block from width
bgt 10b @ loop line @
@
1: @ busy
@ writing at max 110*32 (LCD_WIDTH/2), the fifo is bigger
@ so polling fifo empty only after each line is save
ldr r7, [r3,#0xc] @ r7 = DBOP_STATUS
tst r7, #DBOP_BUSY @ fifo not empty?
beq 1b @
ldmpc regs=r4-r11 @ restore registers and return
.ltorg @ dump constant pool
.size lcd_write_yuv420_lines, .-lcd_write_yuv420_lines
/****************************************************************************
* void lcd_write_yuv420_lines_odither(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 = yuv_src
@ r1 = width
@ r2 = stride
@ r3 = x_screen
@ [sp] = y_screen
stmfd sp!, { r4-r11, lr } @ save non-scratch
ldmia r0, { r4, r5, r6 } @ r4 = yuv_src[0] = Y'_p
@ r5 = yuv_src[1] = Cb_p
@ r6 = yuv_src[2] = Cr_p
@
ldr r14, [sp, #36] @ Line up pattern and kernel quadrant
sub r2, r2, #1 @ stride =- 1
eor r14, r14, r3 @
and r14, r14, #0x2 @
mov r14, r14, lsl #6 @ 0x00 or 0x80
mov r3, #0xC8000000 @
orr r3, r3, #0x120000 @ r3 = DBOP_BASE, need to be redone
@ due to lack of registers
ldr r12, [r3, #8] @
orr r12, r12, #3<<13 @ DBOP_CTRL |= (1<<13|1<<14)
#ifdef SANSA_FUZEV2
bic r12, r12, #1<<13 @ DBOP_CTRL &= ~(1<<13), still 32bit mode
#endif
str r12, [r3, #8] @ (32bit mode)
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 r0, r8, r7 @ r0 = 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, r0, r0, lsr #5 @ r0 = 31/32*b + b/256
add r0, r12, r0, 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 r0, r0, r12 @ b = r0 + delta
add r11, r11, r12, lsl #1 @ r = r11 + delta*2
add r7, r7, r12, lsr #1 @ g = r7 + delta/2
@
orr r12, r0, 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, r0, asr #15 @ clamp b
mvnne r0, r12, lsr #15 @
andne r0, r0, #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, r2] @ r12 = Y' = *(Y'_p + stride)
@
and r11, r11, #0xf800 @ pack pixel
and r7, r7, #0x7e00 @ r0 = pixel = (r & 0xf800) |
orr r11, r11, r7, lsr #4 @ ((g & 0x7e00) >> 4) |
orr r3, r11, r0, lsr #10 @ (b >> 10)
#ifdef SANSA_FUZEV2
mov r7, r3, lsr #8 @
bic r3, r3, #0xff00 @
orr r3, r7, r3, lsl #8 @ swap pixel
#endif
@ save pixel
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 r0, r8, r7 @ r0 = b' = Y + bu
add r11, r9, r7, asl #1 @ r11 = r' = Y*2 + rv
rsb r7, r10, r7 @ r7 = g' = Y + guv
@
sub r12, r0, r0, lsr #5 @ r0 = 31/32*b' + b'/256
add r0, r12, r0, 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 r0, r0, r12 @ b = r0 + delta
add r11, r11, r12, lsl #1 @ r = r11 + delta*2
add r7, r7, r12, lsr #1 @ g = r7 + delta/2
@
orr r12, r0, 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, r0, asr #15 @ clamp b
mvnne r0, r12, lsr #15 @
andne r0, r0, #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 @ r0 = pixel = (r & 0xf800) |
orr r11, r11, r7, lsr #4 @ ((g & 0x7e00) >> 4) |
orr r0, r11, r0, lsr #10 @ (b >> 10)
#ifdef SANSA_FUZEV2
mov r7, r0, lsr #8 @
bic r0, r0, #0xff00 @
orr r0, r7, r0, lsl #8 @ swap pixel
#endif
orr r3, r3, r0, lsl#16 @ pack with 2nd pixel
mov r0, #0xC8000000 @
orr r0, r0, #0x120000 @ r3 = DBOP_BASE
str r3, [r0, #0x10] @ write pixel
@
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 r0, r8, r7 @ r0 = 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, r0, r0, lsr #5 @ r0 = 31/32*b' + b'/256
add r0, r12, r0, 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 r0, r0, r12 @ b = r0 + delta
add r11, r11, r12, lsl #1 @ r = r11 + delta*2
add r7, r7, r12, lsr #1 @ g = r7 + delta/2
@
orr r12, r0, 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, r0, asr #15 @ clamp b
mvnne r0, r12, lsr #15 @
andne r0, r0, #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, r2] @ r12 = Y' = *(Y'_p + stride)
@
and r11, r11, #0xf800 @ pack pixel
and r7, r7, #0x7e00 @ r0 = pixel = (r & 0xf800) |
orr r11, r11, r7, lsr #4 @ ((g & 0x7e00) >> 4) |
orr r3, r11, r0, lsr #10 @ (b >> 10)
#ifdef SANSA_FUZEV2
mov r7, r3, lsr #8 @
bic r3, r3, #0xff00 @
orr r3, r7, r3, lsl #8 @ swap pixel
#endif
@ save pixel
@
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 r0, r8, r7 @ r0 = b' = Y + bu
add r11, r9, r7, asl #1 @ r11 = r' = Y*2 + rv
rsb r7, r10, r7 @ r7 = g' = Y + guv
@
sub r12, r0, r0, lsr #5 @ r0 = 31/32*b + b/256
add r0, r12, r0, 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 r0, r0, r14 @ b = r0 + delta
add r11, r11, r14, lsl #1 @ r = r11 + delta*2
add r7, r7, r14, lsr #1 @ g = r7 + delta/2
@
orr r12, r0, 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, r0, asr #15 @ clamp b
mvnne r0, r12, lsr #15 @
andne r0, r0, #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 @ r0 = pixel = (r & 0xf800) |
orr r11, r11, r7, lsr #4 @ ((g & 0x7e00) >> 4) |
orr r0, r11, r0, lsr #10 @ (b >> 10)
#ifdef SANSA_FUZEV2
mov r7, r0, lsr #8 @
bic r0, r0, #0xff00 @
orr r0, r7, r0, lsl #8 @ swap pixel
#endif
orr r3, r3, r0, lsl#16 @ pack with 2nd pixel
mov r0, #0xC8000000 @
orr r0, r0, #0x120000 @ r3 = DBOP_BASE
str r3, [r0, #0x10] @ write pixel
@
subs r1, r1, #2 @ subtract block from width
bgt 10b @ loop line @
@
1: @ busy @
@ writing at max 110*32 (LCD_WIDTH/2), the fifo is bigger (128*32)
@ so polling fifo empty only after each line is save
ldr r7, [r0,#0xc] @ r7 = DBOP_STATUS
tst r7, #DBOP_BUSY @ fifo not empty?
beq 1b @
ldmpc regs=r4-r11 @ restore registers and return
.ltorg @ dump constant pool
.size lcd_write_yuv420_lines_odither, .-lcd_write_yuv420_lines_odither
|
