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/* ----------------------------------------------------------------------- *
*
* Copyright 2005-2008 H. Peter Anvin - All Rights Reserved
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom
* the Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall
* be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* ----------------------------------------------------------------------- */
/*
* idle.c
*
* What to do in a busy loop...
*/
#include <stddef.h>
#include <com32.h>
#include <sys/cpu.h>
#include <syslinux/idle.h>
void syslinux_idle(void)
{
static int do_idle = 1;
static const com32sys_t sys_idle = {
.eax.l = 0x0013,
};
com32sys_t idle_result;
/* This call isn't supported on SYSLINUX < 3.08, but all it does
is return an error, so we don't care. */
if ( do_idle ) {
__intcall(0x22, &sys_idle, &idle_result);
do_idle = ~idle_result.eflags.l & EFLAGS_CF;
}
cpu_relax();
}
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