diff options
Diffstat (limited to 'roms/u-boot/arch/arm/cpu/armv7/s5p-common/timer.c')
-rw-r--r-- | roms/u-boot/arch/arm/cpu/armv7/s5p-common/timer.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/roms/u-boot/arch/arm/cpu/armv7/s5p-common/timer.c b/roms/u-boot/arch/arm/cpu/armv7/s5p-common/timer.c new file mode 100644 index 000000000..8141f40d5 --- /dev/null +++ b/roms/u-boot/arch/arm/cpu/armv7/s5p-common/timer.c @@ -0,0 +1,139 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2009 Samsung Electronics + * Heungjun Kim <riverful.kim@samsung.com> + * Inki Dae <inki.dae@samsung.com> + * Minkyu Kang <mk7.kang@samsung.com> + */ + +#include <common.h> +#include <div64.h> +#include <init.h> +#include <time.h> +#include <asm/global_data.h> +#include <asm/io.h> +#include <asm/arch/pwm.h> +#include <asm/arch/clk.h> +#include <linux/delay.h> + +/* Use the old PWM interface for now */ +#undef CONFIG_DM_PWM +#include <pwm.h> + +DECLARE_GLOBAL_DATA_PTR; + +unsigned long get_current_tick(void); +static void reset_timer_masked(void); + +/* macro to read the 16 bit timer */ +static inline struct s5p_timer *s5p_get_base_timer(void) +{ + return (struct s5p_timer *)samsung_get_base_timer(); +} + +/** + * Read the countdown timer. + * + * This operates at 1MHz and counts downwards. It will wrap about every + * hour (2^32 microseconds). + * + * @return current value of timer + */ +static unsigned long timer_get_us_down(void) +{ + struct s5p_timer *const timer = s5p_get_base_timer(); + + return readl(&timer->tcnto4); +} + +int timer_init(void) +{ + /* PWM Timer 4 */ + pwm_init(4, MUX_DIV_4, 0); + pwm_config(4, 100000, 100000); + pwm_enable(4); + + /* Use this as the current monotonic time in us */ + gd->arch.timer_reset_value = 0; + + /* Use this as the last timer value we saw */ + gd->arch.lastinc = timer_get_us_down(); + reset_timer_masked(); + + return 0; +} + +/* + * timer without interrupts + */ +unsigned long get_timer(unsigned long base) +{ + unsigned long long time_ms; + + ulong now = timer_get_us_down(); + + /* + * Increment the time by the amount elapsed since the last read. + * The timer may have wrapped around, but it makes no difference to + * our arithmetic here. + */ + gd->arch.timer_reset_value += gd->arch.lastinc - now; + gd->arch.lastinc = now; + + /* Divide by 1000 to convert from us to ms */ + time_ms = gd->arch.timer_reset_value; + do_div(time_ms, 1000); + return time_ms - base; +} + +unsigned long __attribute__((no_instrument_function)) timer_get_us(void) +{ + static unsigned long base_time_us; + + struct s5p_timer *const timer = + (struct s5p_timer *)samsung_get_base_timer(); + unsigned long now_downward_us = readl(&timer->tcnto4); + + if (!base_time_us) + base_time_us = now_downward_us; + + /* Note that this timer counts downward. */ + return base_time_us - now_downward_us; +} + +/* delay x useconds */ +void __udelay(unsigned long usec) +{ + unsigned long count_value; + + count_value = timer_get_us_down(); + while ((int)(count_value - timer_get_us_down()) < (int)usec) + ; +} + +static void reset_timer_masked(void) +{ + struct s5p_timer *const timer = s5p_get_base_timer(); + + /* reset time */ + gd->arch.lastinc = readl(&timer->tcnto4); + gd->arch.tbl = 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. + */ +unsigned long get_tbclk(void) +{ + return CONFIG_SYS_HZ; +} |