Add some CACHEALIGN_* macros and a helper function to assist in aligning data and buffers on PortalPlayer processors to cache line boundaries. They're noops when PROC_NEED_CACHEALIGN isn't defined. Go safe and increase the value to 32 since I'm not sure yet if 16 is sufficient - changing that is a one-liner. Add helper to plugin API which will be needed shortly.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@15523 a1c6a512-1295-4272-9138-f99709370657

2 files changed, 18 insertions, 1 deletions

diff --git a/apps/plugin.c b/apps/plugin.c
index ff23a55537..a80e9dd86d 100644
--- a/apps/plugin.c
+++ b/apps/plugin.c
@@ -518,6 +518,10 @@ static const struct plugin_api rockbox_api = {
 #endif
 
     thread_wait,
+
+#ifdef PROC_NEEDS_CACHEALIGN
+    align_buffer,
+#endif
 };
 
 int plugin_load(const char* plugin, void* parameter)
diff --git a/apps/plugin.h b/apps/plugin.h
index 300cad0781..f56590c29e 100644
--- a/apps/plugin.h
+++ b/apps/plugin.h
@@ -37,6 +37,7 @@
 #include "config.h"
 #include "system.h"
 #include "dir.h"
+#include "general.h"
 #include "kernel.h"
 #include "thread.h"
 #include "button.h"
@@ -112,7 +113,7 @@
 #define PLUGIN_MAGIC 0x526F634B /* RocK */
 
 /* increase this every time the api struct changes */
-#define PLUGIN_API_VERSION 88
+#define PLUGIN_API_VERSION 89
 
 /* update this to latest version if a change to the api struct breaks
    backwards compatibility (and please take the opportunity to sort in any
@@ -640,6 +641,10 @@ struct plugin_api {
 #endif
 
     void (*thread_wait)(struct thread_entry *thread);
+
+#ifdef PROC_NEEDS_CACHEALIGN
+    size_t (*align_buffer)(void **start, size_t size, size_t align);
+#endif
 };
 
 /* plugin header */
@@ -742,4 +747,12 @@ enum plugin_status plugin_start(struct plugin_api* rockbox, void* parameter)
 
 #endif /* CACHE_FUNCTION_WRAPPERS */
 
+#ifndef ALIGN_BUFFER_WRAPPER
+#define ALIGN_BUFFER_WRAPPER(api) \
+        size_t align_buffer(void **start, size_t size, size_t align) \
+        { \
+            return (api)->align_buffer(start, size, align); \
+        }
+#endif /* ALIGN_BUFFER_WRAPPER */
+
 #endif