diff options
Diffstat (limited to 'firmware/target/arm/gigabeat/meg-fx/lcd-as-meg-fx.S')
| -rw-r--r-- | firmware/target/arm/gigabeat/meg-fx/lcd-as-meg-fx.S | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/firmware/target/arm/gigabeat/meg-fx/lcd-as-meg-fx.S b/firmware/target/arm/gigabeat/meg-fx/lcd-as-meg-fx.S new file mode 100644 index 0000000000..414f26d3c5 --- /dev/null +++ b/firmware/target/arm/gigabeat/meg-fx/lcd-as-meg-fx.S @@ -0,0 +1,222 @@ +/*************************************************************************** + * __________ __ ___. + * Open \______ \ ____ ____ | | _\_ |__ _______ ___ + * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / + * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < + * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ + * \/ \/ \/ \/ \/ + * $Id:$ + * + * Copyright (C) 2007 by Michael Sevakis + * + * All files in this archive are subject to the GNU General Public License. + * See the file COPYING in the source tree root for full license agreement. + * + * 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_write_yuv_420_lines(fb_data *dst, + * unsigned char chroma_buf[3][LCD_HEIGHT/2], + 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 + */ + .section .icode, "ax", %progbits + .align 2 + .global lcd_write_yuv420_lines + .type lcd_write_yuv420_lines, %function +lcd_write_yuv420_lines: + @ r0 = dst + @ r1 = chroma_buf + @ r2 = yuv_src + @ r3 = width + @ [sp] = stride + stmdb sp!, { r4-r12, lr } @ save non-scratch + stmdb sp!, { r0, r3 } @ save dst and width + mov r14, #74 @ r14 = Y factor + ldmia r2, { r4, r5, r6 } @ r4 = yuv_src[0] = Y'_p + @ r5 = yuv_src[1] = Cb_p + @ r6 = yuv_src[2] = Cr_p +10: @ loop line 1 @ + ldrb r2, [r4], #1 @ r2 = *Y'_p++; + ldrb r8, [r5], #1 @ r8 = *Cb_p++; + ldrb r11, [r6], #1 @ r11 = *Cr_p++; + @ + @ compute Y + sub r2, r2, #16 @ r7 = Y = (Y' - 16)*74 + mul r7, r2, r14 @ + @ + sub r8, r8, #128 @ Cb -= 128 + sub r11, r11, #128 @ Cr -= 128 + @ + mvn r2, #24 @ compute guv + mul r10, r2, r8 @ r10 = Cb*-24 + mvn r2, #51 @ + mla r10, r2, r11, r10 @ r10 = r10 + Cr*-51 + @ + mov r2, #101 @ compute rv + mul r9, r11, r2 @ r9 = rv = Cr*101 + @ + @ store chromas in line buffer + add r8, r8, #2 @ bu = (Cb + 2) >> 2 + mov r8, r8, asr #2 @ + strb r8, [r1], #1 @ + add r9, r9, #256 @ rv = (Cr + 256) >> 9 + mov r9, r9, asr #9 @ + strb r9, [r1], #1 @ + mov r10, r10, asr #8 @ guv >>= 8 + strb r10, [r1], #1 @ + @ compute R, G, and B + add r2, r8, r7, asr #9 @ r2 = b = (Y >> 9) + bu + add r11, r9, r7, asr #9 @ r11 = r = (Y >> 9) + rv + add r7, r10, r7, asr #8 @ r7 = g = (Y >> 8) + guv + @ + orr r12, r2, r11 @ check if clamping is needed... + orr r12, r12, r7, asr #1 @ ...at all + cmp r12, #31 @ + bls 15f @ no clamp @ + mov r12, #31 @ + cmp r12, r2 @ clamp b + andlo r2, r12, r2, asr #31 @ + eorlo r2, r2, r12 @ + cmp r12, r11 @ clamp r + andlo r11, r12, r11, asr #31 @ + eorlo r11, r11, r12 @ + cmp r12, r7, asr #1 @ clamp g + andlo r7, r12, r7, asr #31 @ + eorlo r7, r7, r12 @ + orrlo r7, r7, r7, asl #1 @ +15: @ no clamp @ + @ + orr r12, r2, r7, lsl #5 @ r4 |= (g << 5) + ldrb r2, [r4], #1 @ r2 = Y' = *Y'_p++ + orr r12, r12, r11, lsl #11 @ r4 = b | (r << 11) + strh r12, [r0], #240 @ store pixel + @ + sub r2, r2, #16 @ r7 = Y = (Y' - 16)*74 + mul r7, r2, r14 @ next Y + @ compute R, G, and B + add r2, r8, r7, asr #9 @ r2 = b = (Y >> 9) + bu + add r11, r9, r7, asr #9 @ r11 = r = (Y >> 9) + rv + add r7, r10, r7, asr #8 @ r7 = g = (Y >> 8) + guv + @ + orr r12, r2, r11 @ check if clamping is needed... + orr r12, r12, r7, asr #1 @ ...at all + cmp r12, #31 @ + bls 15f @ no clamp @ + mov r12, #31 @ + cmp r12, r2 @ clamp b + andlo r2, r12, r2, asr #31 @ + eorlo r2, r2, r12 @ + cmp r12, r11 @ clamp r + andlo r11, r12, r11, asr #31 @ + eorlo r11, r11, r12 @ + cmp r12, r7, asr #1 @ clamp g + andlo r7, r12, r7, asr #31 @ + eorlo r7, r7, r12 @ + orrlo r7, r7, r7, asl #1 @ +15: @ no clamp @ + @ + orr r12, r2, r11, lsl #11 @ r4 = b | (r << 11) + orr r12, r12, r7, lsl #5 @ r4 |= (g << 5) + strh r12, [r0, #240]! @ store pixel + add r0, r0, #2*240 @ + @ + subs r3, r3, #2 @ + bgt 10b @ loop line 1 @ + @ do second line + @ + ldmia sp!, { r0, r3 } @ pop dst and width + sub r0, r0, #2 @ set dst to start of next line @ + sub r1, r1, r3, asl #1 @ rewind chroma pointer... + ldr r2, [sp, #40] @ r2 = stride + add r1, r1, r3, asr #1 @ ... (r1 -= width/2*3) + @ move sources to start of next line + sub r2, r2, r3 @ r2 = skip = stride - width + add r4, r4, r2 @ r4 = Y'_p + skip + @ +20: @ loop line 2 @ + ldrb r2, [r4], #1 @ r7 = Y' = *Y'_p++ + ldrsb r8, [r1], #1 @ reload saved chromas + ldrsb r9, [r1], #1 @ + ldrsb r10, [r1], #1 @ + @ + sub r2, r2, #16 @ r2 = Y = (Y' - 16)*74 + mul r7, r2, r14 @ + @ compute R, G, and B + add r2, r8, r7, asr #9 @ r2 = b = (Y >> 9) + bu + add r11, r9, r7, asr #9 @ r11 = r = (Y >> 9) + rv + add r7, r10, r7, asr #8 @ r7 = g = (Y >> 8) + guv + @ + orr r12, r2, r11 @ check if clamping is needed... + orr r12, r12, r7, asr #1 @ ...at all + cmp r12, #31 @ + bls 25f @ no clamp @ + mov r12, #31 @ + cmp r12, r2 @ clamp b + andlo r2, r12, r2, asr #31 @ + eorlo r2, r2, r12 @ + cmp r12, r11 @ clamp r + andlo r11, r12, r11, asr #31 @ + eorlo r11, r11, r12 @ + cmp r12, r7, asr #1 @ clamp g + andlo r7, r12, r7, asr #31 @ + eorlo r7, r7, r12 @ + orrlo r7, r7, r7, asl #1 @ +25: @ no clamp @ + @ + orr r12, r2, r11, lsl #11 @ r4 = b | (r << 11) + ldrb r2, [r4], #1 @ r2 = Y' = *Y'_p++ + orr r12, r12, r7, lsl #5 @ r4 |= (g << 5) + strh r12, [r0], #240 @ store pixel + @ + @ do second pixel + @ + sub r2, r2, #16 @ r2 = Y = (Y' - 16)*74 + mul r7, r2, r14 @ + @ compute R, G, and B + add r2, r8, r7, asr #9 @ r2 = b = (Y >> 9) + bu + add r11, r9, r7, asr #9 @ r11 = r = (Y >> 9) + rv + add r7, r10, r7, asr #8 @ r7 = g = (Y >> 8) + guv + @ + orr r12, r2, r11 @ check if clamping is needed... + orr r12, r12, r7, asr #1 @ ...at all + cmp r12, #31 @ + bls 25f @ no clamp @ + mov r12, #31 @ + cmp r12, r2 @ clamp b + andlo r2, r12, r2, asr #31 @ + eorlo r2, r2, r12 @ + cmp r12, r11 @ clamp r + andlo r11, r12, r11, asr #31 @ + eorlo r11, r11, r12 @ + cmp r12, r7, asr #1 @ clamp g + andlo r7, r12, r7, asr #31 @ + eorlo r7, r7, r12 @ + orrlo r7, r7, r7, asl #1 @ +25: @ no clamp @ + @ + orr r12, r2, r11, lsl #11 @ r4 = b | (r << 11) + orr r12, r12, r7, lsl #5 @ r4 |= (g << 5) + strh r12, [r0, #240]! @ store pixel + add r0, r0, #2*240 @ + @ + subs r3, r3, #2 @ + bgt 20b @ loop line 2 @ + @ + ldmia sp!, { r4-r12, pc } @ restore registers and return + .size lcd_write_yuv420_lines, .-lcd_write_yuv420_lines |