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 #include <bcm47xx_nvram.h> 31 #include <bcm47xx_board.h> 32 33 void __init plat_time_init(void) 34 { 35 unsigned long hz = 0; 36 u16 chip_id = 0; 37 char buf[10]; 38 int len; 39 enum bcm47xx_board board = bcm47xx_board_get(); 40 41 /* 42 * Use deterministic values for initial counter interrupt 43 * so that calibrate delay avoids encountering a counter wrap. 44 */ 45 write_c0_count(0); 46 write_c0_compare(0xffff); 47 48 switch (bcm47xx_bus_type) { 49 #ifdef CONFIG_BCM47XX_SSB 50 case BCM47XX_BUS_TYPE_SSB: 51 hz = ssb_cpu_clock(&bcm47xx_bus.ssb.mipscore) / 2; 52 chip_id = bcm47xx_bus.ssb.chip_id; 53 break; 54 #endif 55 #ifdef CONFIG_BCM47XX_BCMA 56 case BCM47XX_BUS_TYPE_BCMA: 57 hz = bcma_cpu_clock(&bcm47xx_bus.bcma.bus.drv_mips) / 2; 58 chip_id = bcm47xx_bus.bcma.bus.chipinfo.id; 59 break; 60 #endif 61 } 62 63 if (chip_id == 0x5354) { 64 len = bcm47xx_nvram_getenv("clkfreq", buf, sizeof(buf)); 65 if (len >= 0 && !strncmp(buf, "200", 4)) 66 hz = 100000000; 67 } 68 69 switch (board) { 70 case BCM47XX_BOARD_ASUS_WL520GC: 71 case BCM47XX_BOARD_ASUS_WL520GU: 72 hz = 100000000; 73 break; 74 default: 75 break; 76 } 77 78 if (!hz) 79 hz = 100000000; 80 81 /* Set MIPS counter frequency for fixed_rate_gettimeoffset() */ 82 mips_hpt_frequency = hz; 83 } 84