From 84ad688473bec2875e171b71040eb9e033c6c206 Mon Sep 17 00:00:00 2001 From: Peter Tyser Date: Mon, 12 Apr 2010 22:28:11 -0500 Subject: arm: Move cpu/$CPU to arch/arm/cpu/$CPU Signed-off-by: Peter Tyser --- arch/arm/cpu/arm_cortexa8/s5pc1xx/timer.c | 195 ++++++++++++++++++++++++++++++ 1 file changed, 195 insertions(+) create mode 100644 arch/arm/cpu/arm_cortexa8/s5pc1xx/timer.c (limited to 'arch/arm/cpu/arm_cortexa8/s5pc1xx/timer.c') diff --git a/arch/arm/cpu/arm_cortexa8/s5pc1xx/timer.c b/arch/arm/cpu/arm_cortexa8/s5pc1xx/timer.c new file mode 100644 index 0000000000..c5df5c5ab5 --- /dev/null +++ b/arch/arm/cpu/arm_cortexa8/s5pc1xx/timer.c @@ -0,0 +1,195 @@ +/* + * Copyright (C) 2009 Samsung Electronics + * Heungjun Kim + * Inki Dae + * Minkyu Kang + * + * 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 +#include +#include +#include + +#define PRESCALER_1 (16 - 1) /* prescaler of timer 2, 3, 4 */ +#define MUX_DIV_2 1 /* 1/2 period */ +#define MUX_DIV_4 2 /* 1/4 period */ +#define MUX_DIV_8 3 /* 1/8 period */ +#define MUX_DIV_16 4 /* 1/16 period */ +#define MUX4_DIV_SHIFT 16 + +#define TCON_TIMER4_SHIFT 20 + +static unsigned long count_value; + +/* Internal tick units */ +static unsigned long long timestamp; /* Monotonic incrementing timer */ +static unsigned long lastdec; /* Last decremneter snapshot */ + +/* macro to read the 16 bit timer */ +static inline struct s5pc1xx_timer *s5pc1xx_get_base_timer(void) +{ + if (cpu_is_s5pc110()) + return (struct s5pc1xx_timer *)S5PC110_TIMER_BASE; + else + return (struct s5pc1xx_timer *)S5PC100_TIMER_BASE; +} + +int timer_init(void) +{ + struct s5pc1xx_timer *const timer = s5pc1xx_get_base_timer(); + u32 val; + + /* + * @ PWM Timer 4 + * Timer Freq(HZ) = + * PCLK / { (prescaler_value + 1) * (divider_value) } + */ + + /* set prescaler : 16 */ + /* set divider : 2 */ + writel((PRESCALER_1 & 0xff) << 8, &timer->tcfg0); + writel((MUX_DIV_2 & 0xf) << MUX4_DIV_SHIFT, &timer->tcfg1); + + if (count_value == 0) { + /* reset initial value */ + /* count_value = 2085937.5(HZ) (per 1 sec)*/ + count_value = get_pclk() / ((PRESCALER_1 + 1) * + (MUX_DIV_2 + 1)); + + /* count_value / 100 = 20859.375(HZ) (per 10 msec) */ + count_value = count_value / 100; + } + + /* set count value */ + writel(count_value, &timer->tcntb4); + lastdec = count_value; + + val = (readl(&timer->tcon) & ~(0x07 << TCON_TIMER4_SHIFT)) | + S5PC1XX_TCON4_AUTO_RELOAD; + + /* auto reload & manual update */ + writel(val | S5PC1XX_TCON4_UPDATE, &timer->tcon); + + /* start PWM timer 4 */ + writel(val | S5PC1XX_TCON4_START, &timer->tcon); + + timestamp = 0; + + return 0; +} + +/* + * timer without interrupts + */ +void reset_timer(void) +{ + reset_timer_masked(); +} + +unsigned long get_timer(unsigned long base) +{ + return get_timer_masked() - base; +} + +void set_timer(unsigned long t) +{ + timestamp = t; +} + +/* delay x useconds */ +void __udelay(unsigned long usec) +{ + unsigned long tmo, tmp; + + if (usec >= 1000) { + /* + * if "big" number, spread normalization + * to seconds + * 1. start to normalize for usec to ticks per sec + * 2. find number of "ticks" to wait to achieve target + * 3. finish normalize. + */ + tmo = usec / 1000; + tmo *= (CONFIG_SYS_HZ * count_value / 10); + tmo /= 1000; + } else { + /* else small number, don't kill it prior to HZ multiply */ + tmo = usec * CONFIG_SYS_HZ * count_value / 10; + tmo /= (1000 * 1000); + } + + /* get current timestamp */ + tmp = get_timer(0); + + /* if setting this fordward will roll time stamp */ + /* reset "advancing" timestamp to 0, set lastdec value */ + /* else, set advancing stamp wake up time */ + if ((tmo + tmp + 1) < tmp) + reset_timer_masked(); + else + tmo += tmp; + + /* loop till event */ + while (get_timer_masked() < tmo) + ; /* nop */ +} + +void reset_timer_masked(void) +{ + struct s5pc1xx_timer *const timer = s5pc1xx_get_base_timer(); + + /* reset time */ + lastdec = readl(&timer->tcnto4); + timestamp = 0; +} + +unsigned long get_timer_masked(void) +{ + struct s5pc1xx_timer *const timer = s5pc1xx_get_base_timer(); + unsigned long now = readl(&timer->tcnto4); + + if (lastdec >= now) + timestamp += lastdec - now; + else + timestamp += lastdec + count_value - now; + + lastdec = now; + + return timestamp; +} + +/* + * 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; +} -- cgit v1.2.1