diff options
Diffstat (limited to 'arch/arm/mach-at91/arm920t/timer.c')
| -rw-r--r-- | arch/arm/mach-at91/arm920t/timer.c | 127 | 
1 files changed, 127 insertions, 0 deletions
| diff --git a/arch/arm/mach-at91/arm920t/timer.c b/arch/arm/mach-at91/arm920t/timer.c new file mode 100644 index 00000000000..6aa29947231 --- /dev/null +++ b/arch/arm/mach-at91/arm920t/timer.c @@ -0,0 +1,127 @@ +/* + * (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> + * + * SPDX-License-Identifier:	GPL-2.0+ + */ + +#include <common.h> + +#include <asm/io.h> +#include <asm/arch/hardware.h> +#include <asm/arch/at91_tc.h> +#include <asm/arch/at91_pmc.h> + +DECLARE_GLOBAL_DATA_PTR; + +/* the number of clocks per CONFIG_SYS_HZ */ +#define TIMER_LOAD_VAL (CONFIG_SYS_HZ_CLOCK/CONFIG_SYS_HZ) + +int timer_init(void) +{ +	at91_tc_t *tc = (at91_tc_t *) ATMEL_BASE_TC; +	at91_pmc_t *pmc = (at91_pmc_t *) ATMEL_BASE_PMC; + +	/* enables TC1.0 clock */ +	writel(1 << ATMEL_ID_TC0, &pmc->pcer);	/* enable clock */ + +	writel(0, &tc->bcr); +	writel(AT91_TC_BMR_TC0XC0S_NONE | AT91_TC_BMR_TC1XC1S_NONE | +		AT91_TC_BMR_TC2XC2S_NONE , &tc->bmr); + +	writel(AT91_TC_CCR_CLKDIS, &tc->tc[0].ccr); +	/* set to MCLK/2 and restart the timer +	when the value in TC_RC is reached */ +	writel(AT91_TC_CMR_TCCLKS_CLOCK1 | AT91_TC_CMR_CPCTRG, &tc->tc[0].cmr); + +	writel(0xFFFFFFFF, &tc->tc[0].idr); /* disable interrupts */ +	writel(TIMER_LOAD_VAL, &tc->tc[0].rc); + +	writel(AT91_TC_CCR_SWTRG | AT91_TC_CCR_CLKEN, &tc->tc[0].ccr); +	gd->arch.lastinc = 0; +	gd->arch.tbl = 0; + +	return 0; +} + +/* + * timer without interrupts + */ +ulong get_timer(ulong base) +{ +	return get_timer_masked() - base; +} + +void __udelay(unsigned long usec) +{ +	udelay_masked(usec); +} + +ulong get_timer_raw(void) +{ +	at91_tc_t *tc = (at91_tc_t *) ATMEL_BASE_TC; +	u32 now; + +	now = readl(&tc->tc[0].cv) & 0x0000ffff; + +	if (now >= gd->arch.lastinc) { +		/* normal mode */ +		gd->arch.tbl += now - gd->arch.lastinc; +	} else { +		/* we have an overflow ... */ +		gd->arch.tbl += now + TIMER_LOAD_VAL - gd->arch.lastinc; +	} +	gd->arch.lastinc = now; + +	return gd->arch.tbl; +} + +ulong get_timer_masked(void) +{ +	return get_timer_raw()/TIMER_LOAD_VAL; +} + +void udelay_masked(unsigned long usec) +{ +	u32 tmo; +	u32 endtime; +	signed long diff; + +	tmo = CONFIG_SYS_HZ_CLOCK / 1000; +	tmo *= usec; +	tmo /= 1000; + +	endtime = get_timer_raw() + tmo; + +	do { +		u32 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) +{ +	return CONFIG_SYS_HZ; +} | 
