2 * Copyright (C) 2009 Samsung Electronics
3 * Heungjun Kim <riverful.kim@samsung.com>
4 * Inki Dae <inki.dae@samsung.com>
5 * Minkyu Kang <mk7.kang@samsung.com>
7 * See file CREDITS for list of people who contributed to this
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation; either version 2 of
13 * the License, or (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
28 #include <asm/arch/pwm.h>
29 #include <asm/arch/clk.h>
32 DECLARE_GLOBAL_DATA_PTR;
34 unsigned long get_current_tick(void);
36 /* macro to read the 16 bit timer */
37 static inline struct s5p_timer *s5p_get_base_timer(void)
39 return (struct s5p_timer *)samsung_get_base_timer();
43 * Read the countdown timer.
45 * This operates at 1MHz and counts downwards. It will wrap about every
46 * hour (2^32 microseconds).
48 * @return current value of timer
50 static unsigned long timer_get_us_down(void)
52 struct s5p_timer *const timer = s5p_get_base_timer();
54 return readl(&timer->tcnto4);
60 pwm_init(4, MUX_DIV_4, 0);
64 /* Use this as the current monotonic time in us */
65 gd->arch.timer_reset_value = 0;
67 /* Use this as the last timer value we saw */
68 gd->arch.lastinc = timer_get_us_down();
75 * timer without interrupts
77 unsigned long get_timer(unsigned long base)
79 ulong now = timer_get_us_down();
82 * Increment the time by the amount elapsed since the last read.
83 * The timer may have wrapped around, but it makes no difference to
84 * our arithmetic here.
86 gd->arch.timer_reset_value += gd->arch.lastinc - now;
87 gd->arch.lastinc = now;
89 /* Divide by 1000 to convert from us to ms */
90 return gd->arch.timer_reset_value / 1000 - base;
93 unsigned long timer_get_us(void)
95 static unsigned long base_time_us;
97 struct s5p_timer *const timer =
98 (struct s5p_timer *)samsung_get_base_timer();
99 unsigned long now_downward_us = readl(&timer->tcnto4);
102 base_time_us = now_downward_us;
104 /* Note that this timer counts downward. */
105 return base_time_us - now_downward_us;
108 /* delay x useconds */
109 void __udelay(unsigned long usec)
111 unsigned long count_value;
113 count_value = timer_get_us_down();
114 while ((int)(count_value - timer_get_us_down()) < (int)usec)
118 void reset_timer_masked(void)
120 struct s5p_timer *const timer = s5p_get_base_timer();
123 gd->arch.lastinc = readl(&timer->tcnto4);
128 * This function is derived from PowerPC code (read timebase as long long).
129 * On ARM it just returns the timer value.
131 unsigned long long get_ticks(void)
137 * This function is derived from PowerPC code (timebase clock frequency).
138 * On ARM it returns the number of timer ticks per second.
140 unsigned long get_tbclk(void)
142 return CONFIG_SYS_HZ;