diff options
Diffstat (limited to 'kernel/arch/mips/bcm47xx/time.c')
-rw-r--r-- | kernel/arch/mips/bcm47xx/time.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/kernel/arch/mips/bcm47xx/time.c b/kernel/arch/mips/bcm47xx/time.c new file mode 100644 index 000000000..74224cf2e --- /dev/null +++ b/kernel/arch/mips/bcm47xx/time.c @@ -0,0 +1,81 @@ +/* + * 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> +#include <bcm47xx_board.h> + +void __init plat_time_init(void) +{ + unsigned long hz = 0; + u16 chip_id = 0; + char buf[10]; + int len; + enum bcm47xx_board board = bcm47xx_board_get(); + + /* + * Use deterministic values for initial counter interrupt + * so that calibrate delay avoids encountering a counter wrap. + */ + write_c0_count(0); + write_c0_compare(0xffff); + + switch (bcm47xx_bus_type) { +#ifdef CONFIG_BCM47XX_SSB + case BCM47XX_BUS_TYPE_SSB: + hz = ssb_cpu_clock(&bcm47xx_bus.ssb.mipscore) / 2; + chip_id = bcm47xx_bus.ssb.chip_id; + break; +#endif +#ifdef CONFIG_BCM47XX_BCMA + case BCM47XX_BUS_TYPE_BCMA: + hz = bcma_cpu_clock(&bcm47xx_bus.bcma.bus.drv_mips) / 2; + chip_id = bcm47xx_bus.bcma.bus.chipinfo.id; + break; +#endif + } + + if (chip_id == 0x5354) { + len = bcm47xx_nvram_getenv("clkfreq", buf, sizeof(buf)); + if (len >= 0 && !strncmp(buf, "200", 4)) + hz = 100000000; + } + + switch (board) { + case BCM47XX_BOARD_ASUS_WL520GC: + case BCM47XX_BOARD_ASUS_WL520GU: + hz = 100000000; + break; + default: + break; + } + + if (!hz) + hz = 100000000; + + /* Set MIPS counter frequency for fixed_rate_gettimeoffset() */ + mips_hpt_frequency = hz; +} |