Include divide-by-zero handling within plugins and codecs for ARM processors.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19834 a1c6a512-1295-4272-9138-f99709370657

apps/codecs.c

@@ -169,7 +169,9 @@ struct codec_api ci = {
 
     /* new stuff at the end, sort into place next time
        the API gets incompatible */
-
+#ifdef CPU_ARM
+    __div0,
+#endif
 };
 
 void codec_get_full_path(char *path, const char *codec_root_fn)

apps/codecs.h

@@ -75,7 +75,7 @@
 #define CODEC_ENC_MAGIC 0x52454E43 /* RENC */
 
 /* increase this every time the api struct changes */
-#define CODEC_API_VERSION 30
+#define CODEC_API_VERSION 31
 
 /* update this to latest version if a change to the api struct breaks
    backwards compatibility (and please take the opportunity to sort in any
@@ -233,7 +233,9 @@ struct codec_api {
 
     /* new stuff at the end, sort into place next time
        the API gets incompatible */
-
+#ifdef CPU_ARM
+    void (*__div0)(void);
+#endif
 };
 
 /* codec header */

apps/codecs/codec_crt0.c

@@ -51,3 +51,10 @@ enum codec_status codec_start(void)
 #endif
     return codec_main();
 }
+
+#ifdef CPU_ARM
+void __attribute__((naked)) __div0(void)
+{
+    asm volatile("bx %0" : : "r"(ci->__div0));
+}
+#endif

apps/plugin.c

@@ -627,6 +627,9 @@ static const struct plugin_api rockbox_api = {
     appsversion,
     /* new stuff at the end, sort into place next time
        the API gets incompatible */
+#ifdef CPU_ARM
+    __div0,
+#endif
 };
 
 int plugin_load(const char* plugin, const void* parameter)

apps/plugin.h

@@ -126,7 +126,7 @@ void* plugin_get_buffer(size_t *buffer_size);
 #define PLUGIN_MAGIC 0x526F634B /* RocK */
 
 /* increase this every time the api struct changes */
-#define PLUGIN_API_VERSION 137
+#define PLUGIN_API_VERSION 138
 
 /* update this to latest version if a change to the api struct breaks
    backwards compatibility (and please take the opportunity to sort in any
@@ -782,6 +782,9 @@ struct plugin_api {
 	const char *appsversion;
     /* new stuff at the end, sort into place next time
        the API gets incompatible */
+#ifdef CPU_ARM
+    void (*__div0)(void);
+#endif
 };
 
 /* plugin header */

apps/plugins/lib/SOURCES

@@ -1,3 +1,7 @@
+#ifdef CPU_ARM
+/* For now, only ARM uses this for __div0 */
+gcc-support.c
+#endif
 oldmenuapi.c
 configfile.c
 fixedpoint.c

apps/plugins/lib/gcc-support.c

@@ -0,0 +1,30 @@
+/***************************************************************************
+*             __________               __   ___.
+*   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+*   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+*   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+*   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+*                     \/            \/     \/    \/            \/
+* $Id$
+*
+* Copyright (C) 2009 by Michael Sevakis
+*
+* Miscellaneous compiler support routines.
+*
+* 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 "plugin.h"
+
+#ifdef CPU_ARM
+void __attribute__((naked)) __div0(void)
+{
+    asm volatile("bx %0" : : "r"(rb->__div0));
+}
+#endif

apps/plugins/plugins.make

@@ -17,6 +17,10 @@ ROCKS := $(subst $(ROOTDIR),$(BUILDDIR),$(ROCKS))
 PLUGINLIB := $(BUILDDIR)/apps/plugins/libplugin.a
 PLUGINLIB_SRC = $(call preprocess, $(APPSDIR)/plugins/lib/SOURCES)
 OTHER_SRC += $(PLUGINLIB_SRC)
+# include gcc-support routines for linking first if in SOURCES
+ifneq "$(findstring gcc-support.c,$(PLUGINLIB_SRC))" ""
+GCCSUPPORT_OBJ := $(BUILDDIR)/apps/plugins/lib/gcc-support.o
+endif
 
 PLUGINLIB_OBJ := $(PLUGINLIB_SRC:.c=.o)
 PLUGINLIB_OBJ := $(PLUGINLIB_OBJ:.S=.o)
@@ -70,7 +74,7 @@ else
  PLUGINLDFLAGS = -T$(PLUGINLINK_LDS) -Wl,--gc-sections -Wl,-Map,$*.map
 endif
 
-$(BUILDDIR)/%.rock: $(BUILDDIR)/%.o $(PLUGINLINK_LDS)
+$(BUILDDIR)/%.rock: $(GCCSUPPORT_OBJ) $(BUILDDIR)/%.o $(PLUGINLINK_LDS)
 	$(call PRINTS,LD $(@F))$(CC) $(PLUGINFLAGS) -o $(BUILDDIR)/$*.elf \
 		$(filter %.o, $^) \
 		$(filter %.a, $^) \

apps/plugins/test_codec.c

@@ -494,6 +494,9 @@ static void init_ci(void)
     ci.semaphore_release = rb->semaphore_release;
 #endif
 
+#ifdef CPU_ARM
+    ci.__div0 = rb->__div0;
+#endif
 }
 
 static void codec_thread(void)

firmware/target/arm/system-arm.h

@@ -24,6 +24,7 @@
 #define nop \
   asm volatile ("nop")
 
+void __div0(void);
 
 /* This gets too complicated otherwise with all the ARM variation and would
    have conflicts with another system-target.h elsewhere so include a