linux/arch/mn10300/lib/delay.c
Akira Takeuchi 368dd5acd1 MN10300: And Panasonic AM34 subarch and implement SMP
Implement the Panasonic MN10300 AM34 CPU subarch and implement SMP support for
MN10300.  Also implement support for the MN2WS0060 processor and the ASB2364
evaluation board which are AM34 based.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:55 +01:00

52 lines
1.1 KiB
C

/* MN10300 Short delay interpolation routines
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <asm/div64.h>
/*
* basic delay loop
*/
void __delay(unsigned long loops)
{
int d0;
asm volatile(
" bra 1f \n"
" .align 4 \n"
"1: bra 2f \n"
" .align 4 \n"
"2: add -1,%0 \n"
" bne 2b \n"
: "=&d" (d0)
: "0" (loops)
: "cc");
}
EXPORT_SYMBOL(__delay);
/*
* handle a delay specified in terms of microseconds
*/
void __udelay(unsigned long usecs)
{
unsigned long start, stop, cnt;
/* usecs * CLK / 1E6 */
stop = __muldiv64u(usecs, MN10300_TSCCLK, 1000000);
start = TMTSCBC;
do {
cnt = start - TMTSCBC;
} while (cnt < stop);
}
EXPORT_SYMBOL(__udelay);