Linux Kernel  3.7.1
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time.c
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1 /*
2  * Copyright (C) 2004 Florian Schirmer <[email protected]>
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 
32 {
33  unsigned long hz = 0;
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  switch (bcm47xx_bus_type) {
43 #ifdef CONFIG_BCM47XX_SSB
44  case BCM47XX_BUS_TYPE_SSB:
45  hz = ssb_cpu_clock(&bcm47xx_bus.ssb.mipscore) / 2;
46  break;
47 #endif
48 #ifdef CONFIG_BCM47XX_BCMA
49  case BCM47XX_BUS_TYPE_BCMA:
50  hz = bcma_cpu_clock(&bcm47xx_bus.bcma.bus.drv_mips) / 2;
51  break;
52 #endif
53  }
54 
55  if (!hz)
56  hz = 100000000;
57 
58  /* Set MIPS counter frequency for fixed_rate_gettimeoffset() */
59  mips_hpt_frequency = hz;
60 }