rockbox/firmware/asm/m68k/beep.c
Michael Sevakis 9a32a7b404 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
2012-02-18 04:50:33 -05:00

42 lines
1.6 KiB
C

/***************************************************************************
* __________ __ ___.
* 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"
"move.l %1, %3 \n"
"add.l %4, %1 \n"
"add.l %3, %3 \n"
"subx.l %3, %3 \n"
"eor.l %5, %3 \n"
"move.l %3, (%0)+ \n"
"subq.l #1, %2 \n"
"bgt.b 1b \n"
: "+a"(out), "+d"(*phase), "+d"(count),
"=&d"(s)
: "r"(step), "d"(amplitude));
}