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 #include <linux/init.h>
26 #include <linux/ssb/ssb.h>
27 #include <asm/time.h>
28 #include <bcm47xx.h>
29 #include <bcm47xx_board.h>
30
plat_time_init(void)31 void __init plat_time_init(void)
32 {
33 unsigned long hz = 0;
34 u16 chip_id = 0;
35 char buf[10];
36 int len;
37 enum bcm47xx_board board = bcm47xx_board_get();
38
39 /*
40 * Use deterministic values for initial counter interrupt
41 * so that calibrate delay avoids encountering a counter wrap.
42 */
43 write_c0_count(0);
44 write_c0_compare(0xffff);
45
46 switch (bcm47xx_bus_type) {
47 #ifdef CONFIG_BCM47XX_SSB
48 case BCM47XX_BUS_TYPE_SSB:
49 hz = ssb_cpu_clock(&bcm47xx_bus.ssb.mipscore) / 2;
50 chip_id = bcm47xx_bus.ssb.chip_id;
51 break;
52 #endif
53 #ifdef CONFIG_BCM47XX_BCMA
54 case BCM47XX_BUS_TYPE_BCMA:
55 hz = bcma_cpu_clock(&bcm47xx_bus.bcma.bus.drv_mips) / 2;
56 chip_id = bcm47xx_bus.bcma.bus.chipinfo.id;
57 break;
58 #endif
59 }
60
61 if (chip_id == 0x5354) {
62 len = bcm47xx_nvram_getenv("clkfreq", buf, sizeof(buf));
63 if (len >= 0 && !strncmp(buf, "200", 4))
64 hz = 100000000;
65 }
66
67 switch (board) {
68 case BCM47XX_BOARD_ASUS_WL520GC:
69 case BCM47XX_BOARD_ASUS_WL520GU:
70 hz = 100000000;
71 break;
72 default:
73 break;
74 }
75
76 if (!hz)
77 hz = 100000000;
78
79 /* Set MIPS counter frequency for fixed_rate_gettimeoffset() */
80 mips_hpt_frequency = hz;
81 }
82