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/*
* (C) Copyright 2000, 2001
* Erik Theisen, Wave 7 Optics, etheisen@mindspring.com.
* base on code by
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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 program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <ppc_asm.tmpl>
#include <ppc_defs.h>
#include <config.h>
#include <watchdog.h>
/*
* unsigned long long get_ticks(void);
*
* read timebase as "long long"
*/
.globl get_ticks
get_ticks:
1: mftbu r3
mftb r4
mftbu r5
cmp 0,r3,r5
bne 1b
blr
/*
* Delay for a number of ticks
*/
.globl wait_ticks
wait_ticks:
stwu r1, -16(r1)
mflr r0 /* save link register */
stw r0, 20(r1) /* Use r0 or GDB will be unhappy */
mr r7, r3 /* save tick count */
bl get_ticks /* Get start time */
/* Calculate end time */
addc r7, r4, r7 /* Compute end time lower */
addze r6, r3 /* and end time upper */
WATCHDOG_RESET /* Trigger watchdog, if needed */
1: bl get_ticks /* Get current time */
subfc r4, r4, r7 /* Subtract current time from end time */
subfe. r3, r3, r6
bge 1b /* Loop until time expired */
mtlr r0 /* restore link register */
addi r1,r1,16
blr
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