diff options
author | Wolfgang Denk <wd@denx.de> | 2010-09-09 19:39:46 (GMT) |
---|---|---|
committer | Wolfgang Denk <wd@denx.de> | 2010-09-09 19:39:46 (GMT) |
commit | 8fea51a4acb0c7da6fb375c9a708c50c0a1b66ad (patch) | |
tree | f6a3d36e35f8f4d1009c367417e918c210b0baf0 /arch/arm/cpu/arm926ejs/mb86r0x/timer.c | |
parent | 40e74c852b76accfe27d832f23ea3020352bc120 (diff) | |
parent | ec99d983418897b120409f71712d41c01a21bf7c (diff) | |
download | u-boot-8fea51a4acb0c7da6fb375c9a708c50c0a1b66ad.tar.xz |
Merge branch 'master' of git://git.denx.de/u-boot-arm
Diffstat (limited to 'arch/arm/cpu/arm926ejs/mb86r0x/timer.c')
-rw-r--r-- | arch/arm/cpu/arm926ejs/mb86r0x/timer.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/arch/arm/cpu/arm926ejs/mb86r0x/timer.c b/arch/arm/cpu/arm926ejs/mb86r0x/timer.c new file mode 100644 index 0000000..9175b71 --- /dev/null +++ b/arch/arm/cpu/arm926ejs/mb86r0x/timer.c @@ -0,0 +1,142 @@ +/* + * (C) Copyright 2007-2008 + * Stelian Pop <stelian.pop@leadtechdesign.com> + * Lead Tech Design <www.leadtechdesign.com> + * + * (C) Copyright 2010 + * Matthias Weisser, Graf-Syteco <weisserm@arcor.de> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * 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 program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * 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., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <div64.h> +#include <common.h> +#include <asm/io.h> +#include <asm/arch/hardware.h> + +#define TIMER_LOAD_VAL 0xffffffff +#define TIMER_FREQ (CONFIG_MB86R0x_IOCLK / 256) + +static unsigned long long timestamp; +static ulong lastdec; + +static inline unsigned long long tick_to_time(unsigned long long tick) +{ + tick *= CONFIG_SYS_HZ; + do_div(tick, TIMER_FREQ); + + return tick; +} + +static inline unsigned long long usec_to_tick(unsigned long long usec) +{ + usec *= TIMER_FREQ; + do_div(usec, 1000000); + + return usec; +} + +/* nothing really to do with interrupts, just starts up a counter. */ +int timer_init(void) +{ + struct mb86r0x_timer * timer = (struct mb86r0x_timer *) + MB86R0x_TIMER_BASE; + ulong ctrl = readl(&timer->control); + + writel(TIMER_LOAD_VAL, &timer->load); + + ctrl |= MB86R0x_TIMER_ENABLE | MB86R0x_TIMER_PRS_8S | + MB86R0x_TIMER_SIZE_32; + + writel(ctrl, &timer->control); + + reset_timer_masked(); + + return 0; +} + +/* + * timer without interrupts + */ +unsigned long long get_ticks(void) +{ + struct mb86r0x_timer * timer = (struct mb86r0x_timer *) + MB86R0x_TIMER_BASE; + ulong now = readl(&timer->value); + + if (now <= lastdec) { + /* normal mode (non roll) */ + /* move stamp forward with absolut diff ticks */ + timestamp += lastdec - now; + } else { + /* we have rollover of incrementer */ + timestamp += lastdec + TIMER_LOAD_VAL - now; + } + lastdec = now; + return timestamp; +} + +void reset_timer_masked(void) +{ + struct mb86r0x_timer * timer = (struct mb86r0x_timer *) + MB86R0x_TIMER_BASE; + + /* capture current value time */ + lastdec = readl(&timer->value); + timestamp = 0; /* start "advancing" time stamp from 0 */ +} + +ulong get_timer_masked(void) +{ + return tick_to_time(get_ticks()); +} + +void __udelay(unsigned long usec) +{ + unsigned long long tmp; + ulong tmo; + + tmo = usec_to_tick(usec); + tmp = get_ticks(); /* get current timestamp */ + + while ((get_ticks() - tmp) < tmo) /* loop till event */ + /*NOP*/; +} + +void reset_timer(void) +{ + reset_timer_masked(); +} + +ulong get_timer(ulong base) +{ + return get_timer_masked() - base; +} + +/* + * This function is derived from PowerPC code (timebase clock frequency). + * On ARM it returns the number of timer ticks per second. + */ +ulong get_tbclk(void) +{ + ulong tbclk; + + tbclk = TIMER_FREQ; + return tbclk; +} |