Extend lc_open() to also being able to load overlay plugins.

For this it needs to look at the plugin header. Since lc_open() doesn't know
it's a plugin, the header needs to be changed slightly to include the new lc_header (which needs to be the first element in plugin_header so it can be casted savely).

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@28054 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 16 insertions, 12 deletions

diff --git a/apps/codecs/codec_crt0.c b/apps/codecs/codec_crt0.c
index fdb7909..c845f79 100644
--- a/apps/codecs/codec_crt0.c
+++ b/apps/codecs/codec_crt0.c
@@ -20,15 +20,10 @@
  ****************************************************************************/
 
 #include "config.h"
-#include "codeclib.h"
+#include "codecs.h"
 
 struct codec_api *ci DATA_ATTR;
 
-extern unsigned char iramcopy[];
-extern unsigned char iramstart[];
-extern unsigned char iramend[];
-extern unsigned char iedata[];
-extern unsigned char iend[];
 extern unsigned char plugin_bss_start[];
 extern unsigned char plugin_end_addr[];
 
@@ -42,14 +37,23 @@ enum codec_status codec_start(void)
 {
 #if (CONFIG_PLATFORM & PLATFORM_NATIVE)
 #ifdef USE_IRAM
-    ci->memcpy(iramstart, iramcopy, iramend - iramstart);
-    ci->memset(iedata, 0, iend - iedata);
-#endif
+    extern char iramcopy[], iramstart[], iramend[], iedata[], iend[];
+    size_t iram_size = iramend - iramstart;
+    size_t ibss_size = iend - iedata;
+    if (iram_size > 0 || ibss_size > 0)
+    {
+        ci->memcpy(iramstart, iramcopy, iram_size);
+        ci->memset(iedata, 0, ibss_size);
+        /* make the icache (if it exists) up to date with the new code */
+        ci->cpucache_invalidate();
+        /* barrier to prevent reordering iram copy and BSS clearing,
+         * because the BSS segment alias the IRAM copy.
+         */
+        asm volatile ("" ::: "memory");
+    }
+#endif /* PLUGIN_USE_IRAM */
     ci->memset(plugin_bss_start, 0, plugin_end_addr - plugin_bss_start);
 #endif
-    /* writeback cleared iedata and bss areas, invalidate icache for
-     * copied code */
-    ci->cpucache_invalidate();
 
     return codec_main();
 }