pit: Create an exynos5420 directory which is nearly a copy of exynos5250.

This change creates an exynos5420 directory with code that will eventually
implement support for the exynos5420 cpu from Samsung. Currently it's a copy
of the exynos5250 directory with the name changed. There are going to be some
problems where headers in src/cpu/samsung/exynos-common include headers in the
exynos5250 directory directly.

Change-Id: Ia8d7244310d32499238bbc171c0c668ec48178e1
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Reviewed-on: http://review.coreboot.org/3644
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

1 files changed, 110 insertions, 0 deletions

diff --git a/src/cpu/samsung/exynos5420/timer.c b/src/cpu/samsung/exynos5420/timer.c
new file mode 100644
index 0000000000..405effac5b
--- /dev/null
+++ b/src/cpu/samsung/exynos5420/timer.c
@@ -0,0 +1,110 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2009 Samsung Electronics
+ *
+ * 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; version 2 of the License.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <console/console.h>
+#include <arch/io.h>
+#include <timer.h>
+#include <delay.h>
+#include "timer.h"
+#include "pwm.h"
+#include "clk.h"
+#include "cpu.h"
+
+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 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);
+}
+
+void 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);
+
+		/* Use this as the current monotonic time in us */
+		timer_reset_value = 0;
+
+		/* Use this as the last timer value we saw */
+		lastinc = timer_get_us_down();
+	}
+}
+
+/*
+ * timer without interrupts
+ */
+unsigned long get_timer(unsigned long base)
+{
+	unsigned long 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.
+	 */
+	timer_reset_value += lastinc - now;
+	lastinc = now;
+
+	/* Divide by 1000 to convert from us to ms */
+	return timer_reset_value / 1000 - base;
+}
+
+/* delay x useconds */
+void udelay(unsigned usec)
+{
+	struct mono_time current, end;
+
+	timer_monotonic_get(&current);
+	end = current;
+	mono_time_add_usecs(&end, usec);
+
+	if (mono_time_after(&current, &end)) {
+		printk(BIOS_EMERG, "udelay: 0x%08x is impossibly large\n",
+				usec);
+		/* There's not much we can do if usec is too big. Use a long,
+		 * paranoid delay value and hope for the best... */
+		end = current;
+		mono_time_add_usecs(&end, USECS_PER_SEC);
+	}
+
+	while (mono_time_before(&current, &end))
+		timer_monotonic_get(&current);
+}
+