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>

6 files changed, 703 insertions, 0 deletions

diff --git a/cpu/arm_cortexa8/s5pc1xx/Makefile b/cpu/arm_cortexa8/s5pc1xx/Makefile
new file mode 100644
index 0000000000..e08d9d87b7
--- /dev/null
+++ b/cpu/arm_cortexa8/s5pc1xx/Makefile
@@ -0,0 +1,53 @@
+#
+# (C) Copyright 2000-2003
+# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+#
+# (C) Copyright 2008
+# Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
+#
+# 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 $(TOPDIR)/config.mk
+
+LIB	= $(obj)lib$(SOC).a
+
+SOBJS	= reset.o
+
+COBJS	+= cache.o
+COBJS	+= clock.o
+COBJS	+= cpu_info.o
+COBJS	+= timer.o
+
+SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS) $(SOBJS))
+
+all:	 $(obj).depend $(LIB)
+
+$(LIB):	$(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
+
+#########################################################################
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+#########################################################################
diff --git a/cpu/arm_cortexa8/s5pc1xx/cache.c b/cpu/arm_cortexa8/s5pc1xx/cache.c
new file mode 100644
index 0000000000..8652a45ff0
--- /dev/null
+++ b/cpu/arm_cortexa8/s5pc1xx/cache.c
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2009 Samsung Electronics
+ * 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/cache.h>
+
+void l2_cache_enable(void)
+{
+	unsigned long i;
+
+	__asm__ __volatile__("mrc p15, 0, %0, c1, c0, 1":"=r"(i));
+	__asm__ __volatile__("orr %0, %0, #0x2":"=r"(i));
+	__asm__ __volatile__("mcr p15, 0, %0, c1, c0, 1":"=r"(i));
+}
+
+void l2_cache_disable(void)
+{
+	unsigned long i;
+
+	__asm__ __volatile__("mrc p15, 0, %0, c1, c0, 1":"=r"(i));
+	__asm__ __volatile__("bic %0, %0, #0x2":"=r"(i));
+	__asm__ __volatile__("mcr p15, 0, %0, c1, c0, 1":"=r"(i));
+}
diff --git a/cpu/arm_cortexa8/s5pc1xx/clock.c b/cpu/arm_cortexa8/s5pc1xx/clock.c
new file mode 100644
index 0000000000..a9e78dd793
--- /dev/null
+++ b/cpu/arm_cortexa8/s5pc1xx/clock.c
@@ -0,0 +1,308 @@
+/*
+ * Copyright (C) 2009 Samsung Electronics
+ * Minkyu Kang <mk7.kang@samsung.com>
+ * Heungjun Kim <riverful.kim@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/clock.h>
+
+#define APLL	0
+#define MPLL	1
+#define EPLL	2
+#define HPLL	3
+#define VPLL	4
+
+#define CLK_M	0
+#define CLK_D	1
+#define CLK_P	2
+
+#ifndef CONFIG_SYS_CLK_FREQ_C100
+#define CONFIG_SYS_CLK_FREQ_C100	12000000
+#endif
+#ifndef CONFIG_SYS_CLK_FREQ_C110
+#define CONFIG_SYS_CLK_FREQ_C110	24000000
+#endif
+
+unsigned long (*get_pclk)(void);
+unsigned long (*get_arm_clk)(void);
+unsigned long (*get_pll_clk)(int);
+
+/* s5pc110: return pll clock frequency */
+static unsigned long s5pc100_get_pll_clk(int pllreg)
+{
+	struct s5pc100_clock *clk = (struct s5pc100_clock *)S5PC1XX_CLOCK_BASE;
+	unsigned long r, m, p, s, mask, fout;
+	unsigned int freq;
+
+	switch (pllreg) {
+	case APLL:
+		r = readl(&clk->apll_con);
+		break;
+	case MPLL:
+		r = readl(&clk->mpll_con);
+		break;
+	case EPLL:
+		r = readl(&clk->epll_con);
+		break;
+	case HPLL:
+		r = readl(&clk->hpll_con);
+		break;
+	default:
+		printf("Unsupported PLL (%d)\n", pllreg);
+		return 0;
+	}
+
+	/*
+	 * APLL_CON: MIDV [25:16]
+	 * MPLL_CON: MIDV [23:16]
+	 * EPLL_CON: MIDV [23:16]
+	 * HPLL_CON: MIDV [23:16]
+	 */
+	if (pllreg == APLL)
+		mask = 0x3ff;
+	else
+		mask = 0x0ff;
+
+	m = (r >> 16) & mask;
+
+	/* PDIV [13:8] */
+	p = (r >> 8) & 0x3f;
+	/* SDIV [2:0] */
+	s = r & 0x7;
+
+	/* FOUT = MDIV * FIN / (PDIV * 2^SDIV) */
+	freq = CONFIG_SYS_CLK_FREQ_C100;
+	fout = m * (freq / (p * (1 << s)));
+
+	return fout;
+}
+
+/* s5pc100: return pll clock frequency */
+static unsigned long s5pc110_get_pll_clk(int pllreg)
+{
+	struct s5pc110_clock *clk = (struct s5pc110_clock *)S5PC1XX_CLOCK_BASE;
+	unsigned long r, m, p, s, mask, fout;
+	unsigned int freq;
+
+	switch (pllreg) {
+	case APLL:
+		r = readl(&clk->apll_con);
+		break;
+	case MPLL:
+		r = readl(&clk->mpll_con);
+		break;
+	case EPLL:
+		r = readl(&clk->epll_con);
+		break;
+	case VPLL:
+		r = readl(&clk->vpll_con);
+		break;
+	default:
+		printf("Unsupported PLL (%d)\n", pllreg);
+		return 0;
+	}
+
+	/*
+	 * APLL_CON: MIDV [25:16]
+	 * MPLL_CON: MIDV [25:16]
+	 * EPLL_CON: MIDV [24:16]
+	 * VPLL_CON: MIDV [24:16]
+	 */
+	if (pllreg == APLL || pllreg == MPLL)
+		mask = 0x3ff;
+	else
+		mask = 0x1ff;
+
+	m = (r >> 16) & mask;
+
+	/* PDIV [13:8] */
+	p = (r >> 8) & 0x3f;
+	/* SDIV [2:0] */
+	s = r & 0x7;
+
+	freq = CONFIG_SYS_CLK_FREQ_C110;
+	if (pllreg == APLL) {
+		if (s < 1)
+			s = 1;
+		/* FOUT = MDIV * FIN / (PDIV * 2^(SDIV - 1)) */
+		fout = m * (freq / (p * (1 << (s - 1))));
+	} else
+		/* FOUT = MDIV * FIN / (PDIV * 2^SDIV) */
+		fout = m * (freq / (p * (1 << s)));
+
+	return fout;
+}
+
+/* s5pc110: return ARM clock frequency */
+static unsigned long s5pc110_get_arm_clk(void)
+{
+	struct s5pc110_clock *clk = (struct s5pc110_clock *)S5PC1XX_CLOCK_BASE;
+	unsigned long div;
+	unsigned long dout_apll, armclk;
+	unsigned int apll_ratio;
+
+	div = readl(&clk->div0);
+
+	/* APLL_RATIO: [2:0] */
+	apll_ratio = div & 0x7;
+
+	dout_apll = get_pll_clk(APLL) / (apll_ratio + 1);
+	armclk = dout_apll;
+
+	return armclk;
+}
+
+/* s5pc100: return ARM clock frequency */
+static unsigned long s5pc100_get_arm_clk(void)
+{
+	struct s5pc100_clock *clk = (struct s5pc100_clock *)S5PC1XX_CLOCK_BASE;
+	unsigned long div;
+	unsigned long dout_apll, armclk;
+	unsigned int apll_ratio, arm_ratio;
+
+	div = readl(&clk->div0);
+
+	/* ARM_RATIO: [6:4] */
+	arm_ratio = (div >> 4) & 0x7;
+	/* APLL_RATIO: [0] */
+	apll_ratio = div & 0x1;
+
+	dout_apll = get_pll_clk(APLL) / (apll_ratio + 1);
+	armclk = dout_apll / (arm_ratio + 1);
+
+	return armclk;
+}
+
+/* s5pc100: return HCLKD0 frequency */
+static unsigned long get_hclk(void)
+{
+	struct s5pc100_clock *clk = (struct s5pc100_clock *)S5PC1XX_CLOCK_BASE;
+	unsigned long hclkd0;
+	uint div, d0_bus_ratio;
+
+	div = readl(&clk->div0);
+	/* D0_BUS_RATIO: [10:8] */
+	d0_bus_ratio = (div >> 8) & 0x7;
+
+	hclkd0 = get_arm_clk() / (d0_bus_ratio + 1);
+
+	return hclkd0;
+}
+
+/* s5pc100: return PCLKD1 frequency */
+static unsigned long get_pclkd1(void)
+{
+	struct s5pc100_clock *clk = (struct s5pc100_clock *)S5PC1XX_CLOCK_BASE;
+	unsigned long d1_bus, pclkd1;
+	uint div, d1_bus_ratio, pclkd1_ratio;
+
+	div = readl(&clk->div0);
+	/* D1_BUS_RATIO: [14:12] */
+	d1_bus_ratio = (div >> 12) & 0x7;
+	/* PCLKD1_RATIO: [18:16] */
+	pclkd1_ratio = (div >> 16) & 0x7;
+
+	/* ASYNC Mode */
+	d1_bus = get_pll_clk(MPLL) / (d1_bus_ratio + 1);
+	pclkd1 = d1_bus / (pclkd1_ratio + 1);
+
+	return pclkd1;
+}
+
+/* s5pc110: return HCLKs frequency */
+static unsigned long get_hclk_sys(int dom)
+{
+	struct s5pc110_clock *clk = (struct s5pc110_clock *)S5PC1XX_CLOCK_BASE;
+	unsigned long hclk;
+	unsigned int div;
+	unsigned int offset;
+	unsigned int hclk_sys_ratio;
+
+	if (dom == CLK_M)
+		return get_hclk();
+
+	div = readl(&clk->div0);
+
+	/*
+	 * HCLK_MSYS_RATIO: [10:8]
+	 * HCLK_DSYS_RATIO: [19:16]
+	 * HCLK_PSYS_RATIO: [27:24]
+	 */
+	offset = 8 + (dom << 0x3);
+
+	hclk_sys_ratio = (div >> offset) & 0xf;
+
+	hclk = get_pll_clk(MPLL) / (hclk_sys_ratio + 1);
+
+	return hclk;
+}
+
+/* s5pc110: return PCLKs frequency */
+static unsigned long get_pclk_sys(int dom)
+{
+	struct s5pc110_clock *clk = (struct s5pc110_clock *)S5PC1XX_CLOCK_BASE;
+	unsigned long pclk;
+	unsigned int div;
+	unsigned int offset;
+	unsigned int pclk_sys_ratio;
+
+	div = readl(&clk->div0);
+
+	/*
+	 * PCLK_MSYS_RATIO: [14:12]
+	 * PCLK_DSYS_RATIO: [22:20]
+	 * PCLK_PSYS_RATIO: [30:28]
+	 */
+	offset = 12 + (dom << 0x3);
+
+	pclk_sys_ratio = (div >> offset) & 0x7;
+
+	pclk = get_hclk_sys(dom) / (pclk_sys_ratio + 1);
+
+	return pclk;
+}
+
+/* s5pc110: return peripheral clock frequency */
+static unsigned long s5pc110_get_pclk(void)
+{
+	return get_pclk_sys(CLK_P);
+}
+
+/* s5pc100: return peripheral clock frequency */
+static unsigned long s5pc100_get_pclk(void)
+{
+	return get_pclkd1();
+}
+
+void s5pc1xx_clock_init(void)
+{
+	if (cpu_is_s5pc110()) {
+		get_pll_clk = s5pc110_get_pll_clk;
+		get_arm_clk = s5pc110_get_arm_clk;
+		get_pclk = s5pc110_get_pclk;
+	} else {
+		get_pll_clk = s5pc100_get_pll_clk;
+		get_arm_clk = s5pc100_get_arm_clk;
+		get_pclk = s5pc100_get_pclk;
+	}
+}
diff --git a/cpu/arm_cortexa8/s5pc1xx/cpu_info.c b/cpu/arm_cortexa8/s5pc1xx/cpu_info.c
new file mode 100644
index 0000000000..f16c0ff130
--- /dev/null
+++ b/cpu/arm_cortexa8/s5pc1xx/cpu_info.c
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2009 Samsung Electronics
+ * 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/clk.h>
+
+/* Default is s5pc100 */
+unsigned int s5pc1xx_cpu_id = 0xC100;
+
+#ifdef CONFIG_ARCH_CPU_INIT
+int arch_cpu_init(void)
+{
+	s5pc1xx_cpu_id = readl(S5PC1XX_PRO_ID);
+	s5pc1xx_cpu_id = 0xC000 | ((s5pc1xx_cpu_id & 0x00FFF000) >> 12);
+
+	s5pc1xx_clock_init();
+
+	return 0;
+}
+#endif
+
+u32 get_device_type(void)
+{
+	return s5pc1xx_cpu_id;
+}
+
+#ifdef CONFIG_DISPLAY_CPUINFO
+int print_cpuinfo(void)
+{
+	char buf[32];
+
+	printf("CPU:\tS5P%X@%sMHz\n",
+			s5pc1xx_cpu_id, strmhz(buf, get_arm_clk()));
+
+	return 0;
+}
+#endif
diff --git a/cpu/arm_cortexa8/s5pc1xx/reset.S b/cpu/arm_cortexa8/s5pc1xx/reset.S
new file mode 100644
index 0000000000..7f6ff9c35f
--- /dev/null
+++ b/cpu/arm_cortexa8/s5pc1xx/reset.S
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2009 Samsung Electronics.
+ * 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 <asm/arch/cpu.h>
+
+#define S5PC100_SWRESET			0xE0200000
+#define S5PC110_SWRESET			0xE0102000
+
+.globl reset_cpu
+reset_cpu:
+	ldr	r1, =S5PC1XX_PRO_ID
+	ldr	r2, [r1]
+	ldr	r4, =0x00010000
+	and	r4, r2, r4
+	cmp	r4, #0
+	bne	110f
+	/* S5PC100 */
+	ldr	r1, =S5PC100_SWRESET
+	ldr	r2, =0xC100
+	b	200f
+110:	/* S5PC110 */
+	ldr	r1, =S5PC110_SWRESET
+	mov	r2, #1
+200:
+	str	r2, [r1]
+_loop_forever:
+	b	_loop_forever
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;
+}