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-rw-r--r--arch/arm/cpu/arm920t/a320/timer.c130
1 files changed, 130 insertions, 0 deletions
diff --git a/arch/arm/cpu/arm920t/a320/timer.c b/arch/arm/cpu/arm920t/a320/timer.c
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+++ b/arch/arm/cpu/arm920t/a320/timer.c
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+/*
+ * (C) Copyright 2009 Faraday Technology
+ * Po-Yu Chuang <ratbert@faraday-tech.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, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <common.h>
+#include <div64.h>
+#include <asm/io.h>
+#include <faraday/ftpmu010.h>
+#include <faraday/fttmr010.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define TIMER_CLOCK 32768
+#define TIMER_LOAD_VAL 0xffffffff
+
+static inline unsigned long long tick_to_time(unsigned long long tick)
+{
+ tick *= CONFIG_SYS_HZ;
+ do_div(tick, gd->arch.timer_rate_hz);
+
+ return tick;
+}
+
+static inline unsigned long long usec_to_tick(unsigned long long usec)
+{
+ usec *= gd->arch.timer_rate_hz;
+ do_div(usec, 1000000);
+
+ return usec;
+}
+
+int timer_init(void)
+{
+ struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE;
+ unsigned int cr;
+
+ debug("%s()\n", __func__);
+
+ /* disable timers */
+ writel(0, &tmr->cr);
+
+ /* use 32768Hz oscillator for RTC, WDT, TIMER */
+ ftpmu010_32768osc_enable();
+
+ /* setup timer */
+ writel(TIMER_LOAD_VAL, &tmr->timer3_load);
+ writel(TIMER_LOAD_VAL, &tmr->timer3_counter);
+ writel(0, &tmr->timer3_match1);
+ writel(0, &tmr->timer3_match2);
+
+ /* we don't want timer to issue interrupts */
+ writel(FTTMR010_TM3_MATCH1 |
+ FTTMR010_TM3_MATCH2 |
+ FTTMR010_TM3_OVERFLOW,
+ &tmr->interrupt_mask);
+
+ cr = readl(&tmr->cr);
+ cr |= FTTMR010_TM3_CLOCK; /* use external clock */
+ cr |= FTTMR010_TM3_ENABLE;
+ writel(cr, &tmr->cr);
+
+ gd->arch.timer_rate_hz = TIMER_CLOCK;
+ gd->arch.tbu = gd->arch.tbl = 0;
+
+ return 0;
+}
+
+/*
+ * Get the current 64 bit timer tick count
+ */
+unsigned long long get_ticks(void)
+{
+ struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE;
+ ulong now = TIMER_LOAD_VAL - readl(&tmr->timer3_counter);
+
+ /* increment tbu if tbl has rolled over */
+ if (now < gd->arch.tbl)
+ gd->arch.tbu++;
+ gd->arch.tbl = now;
+ return (((unsigned long long)gd->arch.tbu) << 32) | gd->arch.tbl;
+}
+
+void __udelay(unsigned long usec)
+{
+ unsigned long long start;
+ ulong tmo;
+
+ start = get_ticks(); /* get current timestamp */
+ tmo = usec_to_tick(usec); /* convert usecs to ticks */
+ while ((get_ticks() - start) < tmo)
+ ; /* loop till time has passed */
+}
+
+/*
+ * get_timer(base) can be used to check for timeouts or
+ * to measure elasped time relative to an event:
+ *
+ * ulong start_time = get_timer(0) sets start_time to the current
+ * time value.
+ * get_timer(start_time) returns the time elapsed since then.
+ *
+ * The time is used in CONFIG_SYS_HZ units!
+ */
+ulong get_timer(ulong base)
+{
+ return tick_to_time(get_ticks()) - base;
+}
+
+/*
+ * Return the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+ return gd->arch.timer_rate_hz;
+}
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