diff options
Diffstat (limited to 'cpu/arm920t/at91rm9200/timer.c')
-rw-r--r-- | cpu/arm920t/at91rm9200/timer.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/cpu/arm920t/at91rm9200/timer.c b/cpu/arm920t/at91rm9200/timer.c new file mode 100644 index 0000000..235d107 --- /dev/null +++ b/cpu/arm920t/at91rm9200/timer.c @@ -0,0 +1,160 @@ +/* + * (C) Copyright 2002 + * Lineo, Inc. <www.lineo.com> + * Bernhard Kuhn <bkuhn@lineo.com> + * + * (C) Copyright 2002 + * Sysgo Real-Time Solutions, GmbH <www.elinos.com> + * Marius Groeger <mgroeger@sysgo.de> + * + * (C) Copyright 2002 + * Sysgo Real-Time Solutions, GmbH <www.elinos.com> + * Alex Zuepke <azu@sysgo.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 <common.h> +/*#include <asm/io.h>*/ +#include <asm/arch/hardware.h> +/*#include <asm/proc/ptrace.h>*/ + +/* the number of clocks per CONFIG_SYS_HZ */ +#define TIMER_LOAD_VAL (CONFIG_SYS_HZ_CLOCK/CONFIG_SYS_HZ) + +/* macro to read the 16 bit timer */ +#define READ_TIMER (tmr->TC_CV & 0x0000ffff) +AT91PS_TC tmr; + +static ulong timestamp; +static ulong lastinc; + +int timer_init (void) +{ + tmr = AT91C_BASE_TC0; + + /* enables TC1.0 clock */ + *AT91C_PMC_PCER = 1 << AT91C_ID_TC0; /* enable clock */ + + *AT91C_TCB0_BCR = 0; + *AT91C_TCB0_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_NONE | AT91C_TCB_TC2XC2S_NONE; + tmr->TC_CCR = AT91C_TC_CLKDIS; +#define AT91C_TC_CMR_CPCTRG (1 << 14) + /* set to MCLK/2 and restart the timer when the vlaue in TC_RC is reached */ + tmr->TC_CMR = AT91C_TC_TIMER_DIV1_CLOCK | AT91C_TC_CMR_CPCTRG; + + tmr->TC_IDR = ~0ul; + tmr->TC_RC = TIMER_LOAD_VAL; + lastinc = 0; + tmr->TC_CCR = AT91C_TC_SWTRG | AT91C_TC_CLKEN; + timestamp = 0; + + return (0); +} + +/* + * timer without interrupts + */ + +void reset_timer (void) +{ + reset_timer_masked (); +} + +ulong get_timer (ulong base) +{ + return get_timer_masked () - base; +} + +void set_timer (ulong t) +{ + timestamp = t; +} + +void udelay (unsigned long usec) +{ + udelay_masked(usec); +} + +void reset_timer_masked (void) +{ + /* reset time */ + lastinc = READ_TIMER; + timestamp = 0; +} + +ulong get_timer_raw (void) +{ + ulong now = READ_TIMER; + + if (now >= lastinc) { + /* normal mode */ + timestamp += now - lastinc; + } else { + /* we have an overflow ... */ + timestamp += now + TIMER_LOAD_VAL - lastinc; + } + lastinc = now; + + return timestamp; +} + +ulong get_timer_masked (void) +{ + return get_timer_raw()/TIMER_LOAD_VAL; +} + +void udelay_masked (unsigned long usec) +{ + ulong tmo; + ulong endtime; + signed long diff; + + tmo = CONFIG_SYS_HZ_CLOCK / 1000; + tmo *= usec; + tmo /= 1000; + + endtime = get_timer_raw () + tmo; + + do { + ulong now = get_timer_raw (); + diff = endtime - now; + } while (diff >= 0); +} + +/* + * This function is derived from PowerPC code (read timebase as long long). + * On ARM it just returns the timer value. + */ +unsigned long long get_ticks(void) +{ + return get_timer(0); +} + +/* + * 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 = CONFIG_SYS_HZ; + return tbclk; +} |