WIP: Initial support for Samsung Exynos 5250 ARM CPU

Samsung SoC files, including Exynos5 (a Cortex-A15
implementation). Since this is an SoC we'll forego the x86-style
{north,south}bridge and cpu distinction. We may try to split some
stuff out before the final version if prudent.

Change-Id: Ie068e9dc3dd836c83d90e282b10d5202e7a4ba9b
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: http://review.coreboot.org/2005
Tested-by: build bot (Jenkins)

1 files changed, 153 insertions, 0 deletions

diff --git a/src/cpu/samsung/s5p-common/timer.c b/src/cpu/samsung/s5p-common/timer.c
new file mode 100644
index 0000000000..373c3741d2
--- /dev/null
+++ b/src/cpu/samsung/s5p-common/timer.c
@@ -0,0 +1,153 @@
+/*
+ * 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 <arch/io.h>
+//#include <cpu/samsung/exynos5250/pwm.h>
+//#include <cpu/samsung/exynos5250/clk.h>
+#include <cpu/samsung/s5p-common/pwm.h>
+#include <cpu/samsung/s5p-common/clk.h>
+#include <cpu/samsung/exynos5250/cpu.h>
+#include <cpu/samsung/exynos5-common/exynos5-common.h>
+
+//#include <pwm.h>
+
+//DECLARE_GLOBAL_DATA_PTR;
+static unsigned long long timer_reset_value;
+static unsigned long lastinc;
+
+/* 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 init_timer(void)
+{
+	/* Timer may have been enabled in SPL */
+	if (!pwm_check_enabled(4)) {
+		/* PWM Timer 4 */
+		pwm_init(4, MUX_DIV_4, 0);
+		pwm_config(4, 100000, 100000);
+		pwm_enable(4);
+#ifndef CONFIG_SPL_BUILD
+		/* Use this as the current monotonic time in us */
+		//gd->timer_reset_value = 0;
+		timer_reset_value = 0;
+
+		/* Use this as the last timer value we saw */
+		//gd->lastinc = timer_get_us_down();
+		lastinc = timer_get_us_down();
+#endif
+	}
+
+	return 0;
+}
+
+/*
+ * timer without interrupts
+ */
+unsigned long get_timer(unsigned long base)
+{
+	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.
+	 */
+#if 0
+	gd->timer_reset_value += gd->lastinc - now;
+	gd->lastinc = now;
+
+	/* Divide by 1000 to convert from us to ms */
+	return gd->timer_reset_value / 1000 - base;
+#endif
+	timer_reset_value += lastinc - now;
+	lastinc = now;
+
+	/* Divide by 1000 to convert from us to ms */
+	return timer_reset_value / 1000 - base;
+}
+
+unsigned long timer_get_us(void)
+{
+	struct s5p_timer *const timer = s5p_get_base_timer();
+	unsigned long now_downward_us = readl(&timer->tcnto4);
+
+	/*
+	 * Note that this timer counts downward. The pre-SPL process (BL1)
+	 * takes about 100ms, so add this in here.
+	 */
+	return CONFIG_SPL_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)
+		;
+}
+
+/*
+ * 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;
+}
+
+unsigned long timer_get_boot_us(void)
+{
+	return timer_get_us();
+}