summaryrefslogtreecommitdiffstats
path: root/u-boot/arch/powerpc/lib/time.c
diff options
context:
space:
mode:
Diffstat (limited to 'u-boot/arch/powerpc/lib/time.c')
-rw-r--r--u-boot/arch/powerpc/lib/time.c100
1 files changed, 100 insertions, 0 deletions
diff --git a/u-boot/arch/powerpc/lib/time.c b/u-boot/arch/powerpc/lib/time.c
new file mode 100644
index 0000000..34633c3
--- /dev/null
+++ b/u-boot/arch/powerpc/lib/time.c
@@ -0,0 +1,100 @@
+/*
+ * (C) Copyright 2000, 2001
+ * 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>
+
+/* ------------------------------------------------------------------------- */
+
+/*
+ * This function is intended for SHORT delays only.
+ * It will overflow at around 10 seconds @ 400MHz,
+ * or 20 seconds @ 200MHz.
+ */
+unsigned long usec2ticks(unsigned long usec)
+{
+ ulong ticks;
+
+ if (usec < 1000) {
+ ticks = ((usec * (get_tbclk()/1000)) + 500) / 1000;
+ } else {
+ ticks = ((usec / 10) * (get_tbclk() / 100000));
+ }
+
+ return (ticks);
+}
+
+/* ------------------------------------------------------------------------- */
+
+/*
+ * We implement the delay by converting the delay (the number of
+ * microseconds to wait) into a number of time base ticks; then we
+ * watch the time base until it has incremented by that amount.
+ */
+void __udelay(unsigned long usec)
+{
+ ulong ticks = usec2ticks (usec);
+ wait_ticks (ticks);
+}
+
+/* ------------------------------------------------------------------------- */
+#ifndef CONFIG_NAND_SPL
+unsigned long ticks2usec(unsigned long ticks)
+{
+ ulong tbclk = get_tbclk();
+
+ /* usec = ticks * 1000000 / tbclk
+ * Multiplication would overflow at ~4.2e3 ticks,
+ * so we break it up into
+ * usec = ( ( ticks * 1000) / tbclk ) * 1000;
+ */
+ ticks *= 1000L;
+ ticks /= tbclk;
+ ticks *= 1000L;
+
+ return ((ulong)ticks);
+}
+#endif
+/* ------------------------------------------------------------------------- */
+
+int init_timebase (void)
+{
+ unsigned long temp;
+
+#if defined(CONFIG_5xx) || defined(CONFIG_8xx)
+ volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
+
+ /* unlock */
+ immap->im_sitk.sitk_tbk = KAPWR_KEY;
+#endif
+
+ /* reset */
+ asm volatile("li %0,0 ; mttbu %0 ; mttbl %0;"
+ : "=&r"(temp) );
+
+#if defined(CONFIG_5xx) || defined(CONFIG_8xx)
+ /* enable */
+ immap->im_sit.sit_tbscr |= TBSCR_TBE;
+#endif
+ return (0);
+}
+/* ------------------------------------------------------------------------- */