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authorMichael Sevakis <jethead71@rockbox.org>2012-02-18 04:50:33 -0500
committerMichael Sevakis <jethead71@rockbox.org>2012-02-18 04:50:33 -0500
commit9a32a7b40442e54ee6d8e2403e0f9a154dc4c77f (patch)
treed5aac8ee6999c701c19e69a5f7391517c40216e3 /firmware/asm/arm
parenta794aaa38c9d40e4f0131cd11d8a41441dcd6c4f (diff)
Split CPU-optimized beep code into the firmware/asm tree.
For now due to current lack of an apps/asm, place the ASM/generic code in the firmware/asm directory. Additionally, make generic beep code more generic. Change-Id: I4a69b6ffcbb97d9e6dfde2209c5a118de19e5638
Diffstat (limited to 'firmware/asm/arm')
-rw-r--r--firmware/asm/arm/beep.c39
1 files changed, 39 insertions, 0 deletions
diff --git a/firmware/asm/arm/beep.c b/firmware/asm/arm/beep.c
new file mode 100644
index 0000000000..f3c3e2e0d2
--- /dev/null
+++ b/firmware/asm/arm/beep.c
@@ -0,0 +1,39 @@
+/***************************************************************************
+ * __________ __ ___.
+ * Open \______ \ ____ ____ | | _\_ |__ _______ ___
+ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
+ * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
+ * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
+ * \/ \/ \/ \/ \/
+ * $Id$
+ *
+ * Copyright (c) 2011 Michael Sevakis
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+/* Actually output samples into beep_buf */
+static FORCE_INLINE void beep_generate(uint32_t *out, int count,
+ int32_t *phase, uint32_t step,
+ uint32_t amplitude)
+{
+ uint32_t s;
+
+ asm volatile (
+ "1: \n"
+ "eor %3, %5, %1, asr #31 \n"
+ "subs %2, %2, #1 \n"
+ "str %3, [%0], #4 \n"
+ "add %1, %1, %4 \n"
+ "bgt 1b \n"
+ : "+r"(out), "+r"(*phase), "+r"(count),
+ "=&r"(s)
+ : "r"(step), "r"(amplitude));
+}