sh: First support code of SuperH.

Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>

1 files changed, 94 insertions, 0 deletions

diff --git a/cpu/sh4/time.c b/cpu/sh4/time.c
new file mode 100644
index 0000000..b6e4d02
--- /dev/null
+++ b/cpu/sh4/time.c
@@ -0,0 +1,94 @@
+/*
+ * (C) Copyright 2003
+ * Wolfgang Denk, DENX Software Engineering, wd@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 <common.h>
+#include <asm/processor.h>
+
+#define TMU_MAX_COUNTER (~0UL)
+
+static void tmu_timer_start (unsigned int timer)
+{
+	if (timer > 2)
+		return;
+
+	*((volatile unsigned char *) TSTR0) |= (1 << timer);
+}
+
+int timer_init (void)
+{
+	/* Divide clock by 4 */
+	*(volatile u16 *)TCR0 = 0;
+
+	tmu_timer_start (0);
+	return 0;
+}
+
+/*
+   In theory we should return a true 64bit value (ie something that doesn't
+   overflow). However, we don't. Therefore if TMU runs at fastest rate of
+   6.75 MHz this value will wrap after u-boot has been running for approx
+   10 minutes.
+*/
+unsigned long long get_ticks (void)
+{
+	return (0 - *((volatile unsigned int *) TCNT0));
+}
+
+unsigned long get_timer (unsigned long base)
+{
+	unsigned long n = 
+		*((volatile unsigned int *)TCNT0) ;
+	
+	return ((int)n - base ) < 0 ? ( TMU_MAX_COUNTER - ( base -n )):(n - base );
+}
+
+void set_timer (unsigned long t)
+{
+	*((volatile unsigned int *) TCNT0) = (0 - t);
+}
+
+void reset_timer (void)
+{
+	set_timer (0);
+}
+
+void udelay (unsigned long usec)
+{
+	unsigned int start = get_timer (0);
+	unsigned int end = 0;
+	if (usec > 1000000)
+		end = ((usec/100000) * CFG_HZ) / 10;
+	else if (usec > 1000)
+		end = ((usec/100) * CFG_HZ) / 10000;
+	else
+		end = (usec * CFG_HZ) / 1000000;
+
+	while (get_timer (0) < end)
+		continue;
+}
+
+unsigned long get_tbclk (void)
+{
+	return CFG_HZ;
+}
+