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-rw-r--r--arch/arm/cpu/armv7/socfpga/timer.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/socfpga/timer.c b/arch/arm/cpu/armv7/socfpga/timer.c
new file mode 100644
index 0000000..efa28c2
--- /dev/null
+++ b/arch/arm/cpu/armv7/socfpga/timer.c
@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2012 Altera Corporation <www.altera.com>
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/timer.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static const struct socfpga_timer *timer_base = (void *)CONFIG_SYS_TIMERBASE;
+
+/*
+ * Timer initialization
+ */
+int timer_init(void)
+{
+ writel(TIMER_LOAD_VAL, &timer_base->load_val);
+ writel(TIMER_LOAD_VAL, &timer_base->curr_val);
+ writel(readl(&timer_base->ctrl) | 0x3, &timer_base->ctrl);
+ return 0;
+}
+
+static u32 read_timer(void)
+{
+ return readl(&timer_base->curr_val);
+}
+
+/*
+ * Delay x useconds
+ */
+void __udelay(unsigned long usec)
+{
+ unsigned long now, last;
+ /*
+ * get the tmo value based on timer clock speed
+ * tmo = delay required / period of timer clock
+ */
+ long tmo = usec * CONFIG_TIMER_CLOCK_KHZ / 1000;
+
+ last = read_timer();
+ while (tmo > 0) {
+ now = read_timer();
+ if (last >= now)
+ /* normal mode (non roll) */
+ tmo -= last - now;
+ else
+ /* we have overflow of the count down timer */
+ tmo -= TIMER_LOAD_VAL - last + now;
+ last = now;
+ }
+}
+
+/*
+ * Get the timer value
+ */
+ulong get_timer(ulong base)
+{
+ return get_timer_masked() - base;
+}
+
+/*
+ * Timer : get the time difference
+ * Unit of tick is based on the CONFIG_SYS_HZ
+ */
+ulong get_timer_masked(void)
+{
+ /* current tick value */
+ ulong now = read_timer() / (CONFIG_TIMER_CLOCK_KHZ/CONFIG_SYS_HZ);
+ if (gd->arch.lastinc >= now) {
+ /* normal mode (non roll) */
+ /* move stamp forward with absolute diff ticks */
+ gd->arch.tbl += gd->arch.lastinc - now;
+ } else {
+ /* we have overflow of the count down timer */
+ gd->arch.tbl += TIMER_LOAD_VAL - gd->arch.lastinc + now;
+ }
+ gd->arch.lastinc = now;
+ return gd->arch.tbl;
+}
+
+/*
+ * Reset the timer
+ */
+void reset_timer(void)
+{
+ /* capture current decrementer value time */
+ gd->arch.lastinc = read_timer() /
+ (CONFIG_TIMER_CLOCK_KHZ / CONFIG_SYS_HZ);
+ /* start "advancing" time stamp from 0 */
+ gd->arch.tbl = 0;
+}
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