From 37d43f49f4e26b7df912adcb8894e52544533bef Mon Sep 17 00:00:00 2001
From: Jens Arnold <amiconn@rockbox.org>
Date: Wed, 5 Mar 2008 22:14:13 +0000
Subject: [PATCH] Greyscale library: Assembler optimised update function for
 SH1 (Archos recorders, Ondios), giving ~50% speedup.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@16532 a1c6a512-1295-4272-9138-f99709370657
---
 apps/plugins/lib/SOURCES     |   2 +
 apps/plugins/lib/grey_draw.c |   5 +-
 apps/plugins/lib/grey_sh.S   | 135 +++++++++++++++++++++++++++++++++++
 3 files changed, 140 insertions(+), 2 deletions(-)
 create mode 100644 apps/plugins/lib/grey_sh.S

diff --git a/apps/plugins/lib/SOURCES b/apps/plugins/lib/SOURCES
index b638740b0e..6a44c80ffa 100644
--- a/apps/plugins/lib/SOURCES
+++ b/apps/plugins/lib/SOURCES
@@ -10,6 +10,8 @@ grey_parm.c
 grey_scroll.c
 #ifdef CPU_COLDFIRE
 grey_coldfire.S
+#elif CONFIG_CPU == SH7034
+grey_sh.S
 #endif
 #endif
 highscore.c
diff --git a/apps/plugins/lib/grey_draw.c b/apps/plugins/lib/grey_draw.c
index 6df5556ec8..7b24ba4c70 100644
--- a/apps/plugins/lib/grey_draw.c
+++ b/apps/plugins/lib/grey_draw.c
@@ -635,8 +635,9 @@ void grey_ub_gray_bitmap_part(const unsigned char *src, int src_x, int src_y,
                 + (~yc & _GREY_BMASK);
 #endif /* LCD_PIXELFORMAT */
 
-#if (LCD_PIXELFORMAT == VERTICAL_PACKING) && (LCD_DEPTH == 2) \
- && defined(CPU_COLDFIRE)
+#if (LCD_PIXELFORMAT == VERTICAL_PACKING) && \
+     ((LCD_DEPTH == 2) && defined(CPU_COLDFIRE) \
+      || (LCD_DEPTH == 1) && (CONFIG_CPU == SH7034))
         _grey_line1(width, dst + idx, src, _grey_info.gvalue);
 #else
         unsigned char *dst_row = dst + idx;
diff --git a/apps/plugins/lib/grey_sh.S b/apps/plugins/lib/grey_sh.S
new file mode 100644
index 0000000000..c59c09eaf2
--- /dev/null
+++ b/apps/plugins/lib/grey_sh.S
@@ -0,0 +1,135 @@
+/***************************************************************************
+*             __________               __   ___.
+*   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+*   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+*   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+*   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+*                     \/            \/     \/    \/            \/
+* $Id$
+*
+* New greyscale framework
+* SH1 assembler routines
+*
+* This is a generic framework to display 129 shades of grey on low-depth
+* bitmap LCDs (Archos b&w, Iriver & Ipod 4-grey) within plugins.
+*
+* Copyright (C) 2008 Jens Arnold
+*
+* 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"
+/* Plugins should not normally do this, but we need to check a macro, and
+ * plugin.h would confuse the assembler. */
+ 
+    .text
+    .global     __grey_line1
+    .type       __grey_line1, @function
+    
+#if (LCD_PIXELFORMAT == VERTICAL_PACKING) && (LCD_DEPTH == 1)
+    
+/****************************************************************************
+ * void _grey_line1(int width,                        r4
+ *                  unsigned char *dst,               r5
+ *                  const unsigned char *src,         r6
+ *                  const unsigned char *lut);        r7
+ */
+
+__grey_line1:
+    mov     #1, r0
+    tst     r0, r6
+    bt      .p1_h_end
+    
+    mov.b   @r6+, r0
+    extu.b  r0, r0
+    mov.b   @(r0, r7), r0
+    add     #-1, r4
+    mov.b   r0, @r5
+    add     #8, r5
+.p1_h_end:
+
+    mov     #2, r0
+    cmp/hs  r0, r4
+    bf      .p2_t_end
+    tst     r0, r6
+    bt      .p2_h_end
+    
+    mov.w   @r6+, r1
+    extu.b  r1, r0
+    mov.b   @(r0, r7), r0
+    shlr8   r1
+    mov.b   r0, @(8, r5)
+    extu.b  r1, r0
+    mov.b   @(r0, r7), r0
+    add     #-2, r4
+    mov.b   r0, @r5
+    add     #16, r5
+.p2_h_end:
+
+    add     #-4, r4
+    cmp/pz  r4
+    bf      .p4_end
+
+    add     r6, r4
+
+.p4_loop:
+    mov.l   @r6+, r1
+    swap.w  r1, r2
+    extu.b  r2, r0
+    mov.b   @(r0, r7), r0
+    shlr8   r2
+    mov.b   r0, @(8, r5)
+    extu.b  r2, r0
+    mov.b   @(r0, r7), r2
+    extu.b  r1, r0
+    mov.b   r2, @r5
+    add     #16, r5
+    mov.b   @(r0, r7), r0
+    shlr8   r1
+    mov.b   r0, @(8, r5)
+    extu.b  r1, r0
+    mov.b   @(r0, r7), r0
+    cmp/hs  r6, r4
+    mov.b   r0, @r5
+    add     #16, r5
+    bt      .p4_loop
+    
+    sub     r6, r4
+
+.p4_end:
+    mov     #2, r0
+    tst     r0, r4
+    bt      .p2_t_end
+    
+    mov.w   @r6+, r1
+    extu.b  r1, r0
+    mov.b   @(r0, r7), r0
+    shlr8   r1
+    mov.b   r0, @(8, r5)
+    extu.b  r1, r0
+    mov.b   @(r0, r7), r0
+    mov.b   r0, @r5
+    add     #16, r5
+.p2_t_end:
+
+    mov     #1, r0
+    tst     r0, r4
+    bt      .p1_t_end
+
+    mov.b   @r6+, r0
+    extu.b  r0, r0
+    mov.b   @(r0, r7), r0
+    rts
+    mov.b   r0, @r5
+.p1_t_end:
+
+    rts
+    nop
+    .size   _grey_line1, . - _grey_line1
+
+#endif