c200: First implemention of lcd_yuv_blit(). mpegplayer works now, but speed can be optimized more and dithering is not yet implemented.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@15020 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 243 insertions, 0 deletions

diff --git a/firmware/target/arm/sandisk/sansa-c200/lcd-as-c200.S b/firmware/target/arm/sandisk/sansa-c200/lcd-as-c200.S
new file mode 100644
index 0000000000..9b0cd75bae
--- /dev/null
+++ b/firmware/target/arm/sandisk/sansa-c200/lcd-as-c200.S
@@ -0,0 +1,243 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2007 by Jens Arnold
+ * Heavily based on lcd-as-memframe.c 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(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-r12 }         @ 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
+                                        @ r0 = scratch
+    sub         r2, r2, #1              @
+    mov         r3, #0x70000000         @
+    orr         r3, r3, #0x3000         @ r3 = LCD1_BASE
+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         r0, r8, r7, asr #8      @ r0  = 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, r0, r11            @ 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         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, r2]           @ r12 = Y' = *(Y'_p + stride)
+                                        @
+    mov         r11, r11, lsl #3        @
+    orr         r11, r11, r7, lsr #3    @ r11 = (r << 3) | (g >> 3)
+    orr         r0, r0, r7, lsl #5      @ r0 = (g << 5) | b
+1: @ busy                               @
+    ldr         r7, [r3]                @ r7 = LCD1_BASE
+    tst         r7, #LCD1_BUSY_MASK     @ bridge busy?
+    bne         1b                      @
+    str         r11, [r3, #0x10]        @ send MSB
+1: @busy                                @
+    ldr         r7, [r3]                @ r7 = LCD1_BASE
+    tst         r7, #LCD1_BUSY_MASK     @ bridge busy?
+    bne         1b                      @
+    str         r0, [r3, #0x10]         @ send LSB
+                                        @
+    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         r11, r9, r7, asr #8     @ r11 = r = (Y >> 9) + rv
+    add         r7, r10, r7, asr #7     @ r7  = g = (Y >> 8) + guv
+                                        @
+    orr         r12, r0, r11            @ 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         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++)
+                                        @
+    mov         r11, r11, lsl #3        @
+    orr         r11, r11, r7, lsr #3    @ r11 = (r << 3) | (g >> 3)
+    orr         r0, r0, r7, lsl #5      @ r0 = (g << 5) | b
+1: @ busy                               @
+    ldr         r7, [r3]                @ r7 = LCD1_BASE
+    tst         r7, #LCD1_BUSY_MASK     @ bridge busy?
+    bne         1b                      @
+    str         r11, [r3, #0x10]        @ send MSB
+1: @ busy                               @
+    ldr         r7, [r3]                @ r7 = LCD1_BASE
+    tst         r7, #LCD1_BUSY_MASK     @ bridge busy?
+    bne         1b                      @
+    str         r0, [r3, #0x10]         @ send LSB
+                                        @
+    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         r11, r9, r7, asr #8     @ r11 = r = (Y >> 9) + rv
+    add         r7, r10, r7, asr #7     @ r7  = g = (Y >> 8) + guv
+                                        @
+    orr         r12, r0, r11            @ 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         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, r2]           @ r12 = Y' = *(Y'_p + stride)
+                                        @
+                                        @
+    mov         r11, r11, lsl #3        @
+    orr         r11, r11, r7, lsr #3    @ r11 = (r << 3) | (g >> 3)
+    orr         r0, r0, r7, lsl #5      @ r0 = (g << 5) | b
+1: @ busy                               @
+    ldr         r7, [r3]                @ r7 = LCD1_BASE
+    tst         r7, #LCD1_BUSY_MASK     @ bridge busy?
+    bne         1b                      @
+    str         r11, [r3, #0x10]        @ send MSB
+1: @ busy                               @
+    ldr         r7, [r3]                @ r7 = LCD1_BASE
+    tst         r7, #LCD1_BUSY_MASK     @ bridge busy?
+    bne         1b                      @
+    str         r0, [r3, #0x10]         @ send LSB
+                                        @
+    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         r11, r9, r7, asr #8     @ r11 = r = (Y >> 9) + rv
+    add         r7, r10, r7, asr #7     @ r7  = g = (Y >> 8) + guv
+                                        @
+    orr         r12, r0, r11            @ 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         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                          @
+                                        @
+    mov         r11, r11, lsl #3        @
+    orr         r11, r11, r7, lsr #3    @ r11 = (r << 3) | (g >> 3)
+    orr         r0, r0, r7, lsl #5      @ r0 = (g << 5) | b
+1: @ busy                               @
+    ldr         r7, [r3]                @ r7 = LCD1_BASE
+    tst         r7, #LCD1_BUSY_MASK     @ bridge busy?
+    bne         1b                      @
+    str         r11, [r3, #0x10]        @ send MSB
+1: @ busy                               @
+    ldr         r7, [r3]                @ r7 = LCD1_BASE
+    tst         r7, #LCD1_BUSY_MASK     @ bridge busy?
+    bne         1b                      @
+    str         r0, [r3, #0x10]         @ send LSB
+                                        @
+    subs        r1, r1, #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
+