linux-stable-rt/arch/mips/bcm47xx/time.c

49 lines
1.8 KiB
C

/*
* Copyright (C) 2004 Florian Schirmer <jolt@tuxbox.org>
*
* 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 PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* 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.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/init.h>
#include <linux/ssb/ssb.h>
#include <asm/time.h>
#include <bcm47xx.h>
void __init plat_time_init(void)
{
unsigned long hz;
/*
* Use deterministic values for initial counter interrupt
* so that calibrate delay avoids encountering a counter wrap.
*/
write_c0_count(0);
write_c0_compare(0xffff);
hz = ssb_cpu_clock(&ssb_bcm47xx.mipscore) / 2;
if (!hz)
hz = 100000000;
/* Set MIPS counter frequency for fixed_rate_gettimeoffset() */
mips_hpt_frequency = hz;
}