s5pc1xx: support Samsung s5pc1xx SoC

This patch adds support for the Samsung s5pc100 and s5pc110
SoCs. The s5pc1xx SoC is an ARM Cortex A8 processor.

Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
Signed-off-by: HeungJun, Kim <riverful.kim@samsung.com>

1 files changed, 195 insertions, 0 deletions

diff --git a/cpu/arm_cortexa8/s5pc1xx/timer.c b/cpu/arm_cortexa8/s5pc1xx/timer.c
new file mode 100644
index 0000000000..cdba5d9342
--- /dev/null
+++ b/cpu/arm_cortexa8/s5pc1xx/timer.c
@@ -0,0 +1,195 @@
+/*
+ * Copyright (C) 2009 Samsung Electronics
+ * Heungjun Kim <riverful.kim@samsung.com>
+ * Inki Dae <inki.dae@samsung.com>
+ * Minkyu Kang <mk7.kang@samsung.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/pwm.h>
+#include <asm/arch/clk.h>
+
+#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;
+}