1 /*
2 * Copyright (C) 2004 Florian Schirmer <jolt@tuxbox.org>
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the
6 * Free Software Foundation; either version 2 of the License, or (at your
7 * option) any later version.
8 *
9 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
10 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
12 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
13 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
14 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
15 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
16 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
17 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
18 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
19 *
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 675 Mass Ave, Cambridge, MA 02139, USA.
23 */
24
25
26 #include <linux/init.h>
27 #include <linux/ssb/ssb.h>
28 #include <asm/time.h>
29 #include <bcm47xx.h>
30
plat_time_init(void)31 void __init plat_time_init(void)
32 {
33 unsigned long hz;
34
35 /*
36 * Use deterministic values for initial counter interrupt
37 * so that calibrate delay avoids encountering a counter wrap.
38 */
39 write_c0_count(0);
40 write_c0_compare(0xffff);
41
42 hz = ssb_cpu_clock(&ssb_bcm47xx.mipscore) / 2;
43 if (!hz)
44 hz = 100000000;
45
46 /* Set MIPS counter frequency for fixed_rate_gettimeoffset() */
47 mips_hpt_frequency = hz;
48 }
49