ARM: START/STOP_TIMER support for ARMv7

Originally committed as revision 18305 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavutil/arm/timer.h

+/*
+ * Copyright (c) 2009 Mans Rullgard <mans@mansr.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVUTIL_ARM_TIMER_H
+#define AVUTIL_ARM_TIMER_H
+
+#include <stdint.h>
+
+#if HAVE_INLINE_ASM && defined(__ARM_ARCH_7A__)
+
+#define AV_READ_TIME read_time
+
+static inline uint64_t read_time(void)
+{
+    unsigned cc;
+    __asm__ volatile ("mrc p15, 0, %0, c9, c13, 0" : "=r"(cc));
+    return cc;
+}
+
+#endif /* HAVE_INLINE_ASM && __ARM_ARCH_7A__ */
+
+#endif /* AVUTIL_ARM_TIMER_H */

libavutil/timer.h

@@ -28,7 +28,9 @@
 #include <stdint.h>
 #include "config.h"
 
-#if   ARCH_BFIN
+#if   ARCH_ARM
+#   include "arm/timer.h"
+#elif ARCH_BFIN
 #   include "bfin/timer.h"
 #elif ARCH_PPC
 #   include "ppc/timer.h"