1 files changed, 67 insertions, 0 deletions

diff --git a/firmware/asm/corelock.c b/firmware/asm/corelock.c
new file mode 100644
index 0000000000..51d1d71961
--- /dev/null
+++ b/firmware/asm/corelock.c
@@ -0,0 +1,67 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2007 by Daniel Ankers
+ *
+ * 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 "config.h"
+#include "corelock.h"
+/* Core locks using Peterson's mutual exclusion algorithm. */
+
+#ifdef CPU_ARM
+#include "arm/corelock.c"
+#else
+
+void corelock_lock(struct corelock *cl)
+{
+    const unsigned int core = CURRENT_CORE;
+    const unsigned int othercore = 1 - core;
+
+    cl->myl[core] = core;
+    cl->turn = othercore;
+
+    for (;;)
+    {
+        if (cl->myl[othercore] == 0 || cl->turn == core)
+            break;
+    }
+}
+
+int corelock_try_lock(struct corelock *cl)
+{
+    const unsigned int core = CURRENT_CORE;
+    const unsigned int othercore = 1 - core;
+
+    cl->myl[core] = core;
+    cl->turn = othercore;
+
+    if (cl->myl[othercore] == 0 || cl->turn == core)
+    {
+        return 1;
+    }
+
+    cl->myl[core] = 0;
+    return 0;
+}
+
+void corelock_unlock(struct corelock *cl)
+{
+    cl->myl[CURRENT_CORE] = 0;
+}
+
+#endif