diff options
| author | Bo Shen <voice.shen@atmel.com> | 2013-05-12 22:40:54 +0000 | 
|---|---|---|
| committer | Andreas Bießmann <andreas.devel@googlemail.com> | 2013-05-21 11:54:16 +0200 | 
| commit | 3225f34e5c704a9caf3c69527ee1f822aee15108 (patch) | |
| tree | 9ae7edc8f5e9d02616c4c5e625736a7922fc762e /arch/arm/cpu/armv7/at91/timer.c | |
| parent | e5e8bb05a4cc31624306dbbcc89f99795ff8f462 (diff) | |
| download | olio-uboot-2014.01-3225f34e5c704a9caf3c69527ee1f822aee15108.tar.xz olio-uboot-2014.01-3225f34e5c704a9caf3c69527ee1f822aee15108.zip | |
ARM: atmel: add sama5d3xek support
Add sama5d3xek support with following feature
  - boot from NAND flash, PMECC support, 4bit ECC @ 512 bytes sector
  - boot from SPI flash support
  - boot from SD card support
  - LCD support
  - EMAC support
  - USB OHCI support
Signed-off-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
Diffstat (limited to 'arch/arm/cpu/armv7/at91/timer.c')
| -rw-r--r-- | arch/arm/cpu/armv7/at91/timer.c | 139 | 
1 files changed, 139 insertions, 0 deletions
| diff --git a/arch/arm/cpu/armv7/at91/timer.c b/arch/arm/cpu/armv7/at91/timer.c new file mode 100644 index 000000000..b3a450fb3 --- /dev/null +++ b/arch/arm/cpu/armv7/at91/timer.c @@ -0,0 +1,139 @@ +/* + * (C) Copyright 2007-2008 + * Stelian Pop <stelian@popies.net> + * Lead Tech Design <www.leadtechdesign.com> + * + * (C) Copyright 2013 + * Bo Shen <voice.shen@atmel.com> + * + * 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/arch/at91_pit.h> +#include <asm/arch/at91_pmc.h> +#include <asm/arch/clk.h> +#include <div64.h> + +#if !defined(CONFIG_AT91FAMILY) +# error You need to define CONFIG_AT91FAMILY in your board config! +#endif + +DECLARE_GLOBAL_DATA_PTR; + +/* + * We're using the SAMA5D3x PITC in 32 bit mode, by + * setting the 20 bit counter period to its maximum (0xfffff). + * (See the relevant data sheets to understand that this really works) + * + * We do also mimic the typical powerpc way of incrementing + * two 32 bit registers called tbl and tbu. + * + * Those registers increment at 1/16 the main clock rate. + */ + +#define TIMER_LOAD_VAL	0xfffff + +static inline unsigned long long tick_to_time(unsigned long long tick) +{ +	tick *= CONFIG_SYS_HZ; +	do_div(tick, gd->arch.timer_rate_hz); + +	return tick; +} + +static inline unsigned long long usec_to_tick(unsigned long long usec) +{ +	usec *= gd->arch.timer_rate_hz; +	do_div(usec, 1000000); + +	return usec; +} + +/* + * Use the PITC in full 32 bit incrementing mode + */ +int timer_init(void) +{ +	at91_pit_t *pit = (at91_pit_t *)ATMEL_BASE_PIT; + +	/* Enable PITC Clock */ +	at91_periph_clk_enable(ATMEL_ID_SYS); + +	/* Enable PITC */ +	writel(TIMER_LOAD_VAL | AT91_PIT_MR_EN , &pit->mr); + +	gd->arch.timer_rate_hz = gd->arch.mck_rate_hz / 16; +	gd->arch.tbu = 0; +	gd->arch.tbl = 0; + +	return 0; +} + +/* + * Get the current 64 bit timer tick count + */ +unsigned long long get_ticks(void) +{ +	at91_pit_t *pit = (at91_pit_t *)ATMEL_BASE_PIT; + +	ulong now = readl(&pit->piir); + +	/* increment tbu if tbl has rolled over */ +	if (now < gd->arch.tbl) +		gd->arch.tbu++; +	gd->arch.tbl = now; +	return (((unsigned long long)gd->arch.tbu) << 32) | gd->arch.tbl; +} + +void __udelay(unsigned long usec) +{ +	unsigned long long start; +	ulong tmo; + +	start = get_ticks();		/* get current timestamp */ +	tmo = usec_to_tick(usec);	/* convert usecs to ticks */ +	while ((get_ticks() - start) < tmo) +		;			/* loop till time has passed */ +} + +/* + * get_timer(base) can be used to check for timeouts or + * to measure elasped time relative to an event: + * + * ulong start_time = get_timer(0) sets start_time to the current + * time value. + * get_timer(start_time) returns the time elapsed since then. + * + * The time is used in CONFIG_SYS_HZ units! + */ +ulong get_timer(ulong base) +{ +	return tick_to_time(get_ticks()) - base; +} + +/* + * Return the number of timer ticks per second. + */ +ulong get_tbclk(void) +{ +	return gd->arch.timer_rate_hz; +} |