From d57557c0644f9294e30657f0c7cf673cf2914695 Mon Sep 17 00:00:00 2001
From: notaz <notasas@gmail.com>
Date: Fri, 8 Feb 2013 02:13:03 +0200
Subject: [PATCH] frontend: add armv6 color space converter

---
 Makefile              |  4 +++
 frontend/cspace.c     |  6 +++-
 frontend/cspace_arm.S | 65 +++++++++++++++++++++++++++++++++++++++++++
 jni/Android.mk        |  1 +
 4 files changed, 75 insertions(+), 1 deletion(-)
 create mode 100644 frontend/cspace_arm.S

diff --git a/Makefile b/Makefile
index b6f381cc..9f8b7772 100644
--- a/Makefile
+++ b/Makefile
@@ -129,6 +129,10 @@ OBJS += plugins/dfinput/main.o plugins/dfinput/pad.o plugins/dfinput/guncon.o
 OBJS += frontend/cspace.o
 ifeq "$(HAVE_NEON)" "1"
 OBJS += frontend/cspace_neon.o
+else
+ifeq "$(ARCH)" "arm"
+OBJS += frontend/cspace_arm.o
+endif
 endif
 
 ifeq "$(PLATFORM)" "generic"
diff --git a/frontend/cspace.c b/frontend/cspace.c
index f0c49126..33a981df 100644
--- a/frontend/cspace.c
+++ b/frontend/cspace.c
@@ -15,7 +15,7 @@
  * in favor of NEON version or platform-specific conversion
  */
 
-#ifndef __ARM_NEON__
+#ifndef __arm__
 
 void bgr555_to_rgb565(void *dst_, const void *src_, int bytes)
 {
@@ -32,6 +32,10 @@ void bgr555_to_rgb565(void *dst_, const void *src_, int bytes)
 	}
 }
 
+#endif
+
+#ifndef __ARM_NEON__
+
 void bgr888_to_rgb565(void *dst_, const void *src_, int bytes)
 {
 	const unsigned char *src = src_;
diff --git a/frontend/cspace_arm.S b/frontend/cspace_arm.S
new file mode 100644
index 00000000..e9d15a5b
--- /dev/null
+++ b/frontend/cspace_arm.S
@@ -0,0 +1,65 @@
+/*
+ * (C) Gražvydas "notaz" Ignotas, 2013
+ *
+ * This work is licensed under the terms of GNU GPL version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "arm_features.h"
+
+.text
+.align 2
+
+@ lr=0x001f001f
+@ trashes r11, r12
+.macro bgr555_to_rgb565_one rn
+    and      r11, lr, \rn
+    and      r12, lr, \rn, lsr #5
+    and      \rn, lr, \rn, lsr #10
+    orr      r12, r11, lsl #5
+    orr      \rn, r12, lsl #6
+.endm
+
+.macro pld_ reg offs=#0
+#ifdef HAVE_ARMV6
+    pld      [\reg, \offs]
+#endif
+.endm
+
+.global bgr555_to_rgb565 @ void *dst, const void *src, int bytes
+bgr555_to_rgb565:
+    pld_     r1
+    push     {r4-r11,lr}
+    mov      lr, #0x001f
+    subs     r2, #4*8
+    orr      lr, lr, lsl #16
+    blt      1f
+
+0:
+    ldmia    r1!, {r3-r10}
+    subs     r2, #4*8
+    bgr555_to_rgb565_one r3
+
+    pld_     r1, #32*2
+    bgr555_to_rgb565_one r4
+    bgr555_to_rgb565_one r5
+    bgr555_to_rgb565_one r6
+    bgr555_to_rgb565_one r7
+    bgr555_to_rgb565_one r8
+    bgr555_to_rgb565_one r9
+    bgr555_to_rgb565_one r10
+    stmia    r0!, {r3-r10}
+    bge      0b
+
+1:
+    adds     r2, #4*8
+    popeq    {r4-r11,pc}
+
+2:
+    ldr      r3, [r1], #4
+    subs     r2, #4
+    bgr555_to_rgb565_one r3
+    str      r3, [r0], #4
+    bgt      2b
+
+    pop      {r4-r11,pc}
diff --git a/jni/Android.mk b/jni/Android.mk
index 05a92d46..81962e01 100644
--- a/jni/Android.mk
+++ b/jni/Android.mk
@@ -35,6 +35,7 @@ ifeq ($(TARGET_ARCH),arm)
       # gpu
       LOCAL_CFLAGS += -DREARMED
       LOCAL_SRC_FILES += ../plugins/gpu_unai/gpulib_if.cpp ../plugins/gpu_unai/gpu_arm.s
+      LOCAL_SRC_FILES += ../frontend/cspace_arm.S
    else
       LOCAL_ARM_NEON := true
       LOCAL_CFLAGS += -DNEON_BUILD -DTEXTURE_CACHE_4BPP -DTEXTURE_CACHE_8BPP
-- 
2.39.5