summaryrefslogtreecommitdiffstats
path: root/u-boot/arch/arm/cpu/arm920t/at91/timer.c
diff options
context:
space:
mode:
Diffstat (limited to 'u-boot/arch/arm/cpu/arm920t/at91/timer.c')
-rw-r--r--u-boot/arch/arm/cpu/arm920t/at91/timer.c162
1 files changed, 162 insertions, 0 deletions
diff --git a/u-boot/arch/arm/cpu/arm920t/at91/timer.c b/u-boot/arch/arm/cpu/arm920t/at91/timer.c
new file mode 100644
index 0000000..d9a024f
--- /dev/null
+++ b/u-boot/arch/arm/cpu/arm920t/at91/timer.c
@@ -0,0 +1,162 @@
+/*
+ * (C) Copyright 2002
+ * Lineo, Inc. <www.lineo.com>
+ * Bernhard Kuhn <bkuhn@lineo.com>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.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/arch/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/at91_tc.h>
+#include <asm/arch/at91_pmc.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* the number of clocks per CONFIG_SYS_HZ */
+#define TIMER_LOAD_VAL (CONFIG_SYS_HZ_CLOCK/CONFIG_SYS_HZ)
+
+int timer_init(void)
+{
+ at91_tc_t *tc = (at91_tc_t *) AT91_TC_BASE;
+ at91_pmc_t *pmc = (at91_pmc_t *) AT91_PMC_BASE;
+
+ /* enables TC1.0 clock */
+ writel(1 << AT91_ID_TC0, &pmc->pcer); /* enable clock */
+
+ writel(0, &tc->bcr);
+ writel(AT91_TC_BMR_TC0XC0S_NONE | AT91_TC_BMR_TC1XC1S_NONE |
+ AT91_TC_BMR_TC2XC2S_NONE , &tc->bmr);
+
+ writel(AT91_TC_CCR_CLKDIS, &tc->tc[0].ccr);
+ /* set to MCLK/2 and restart the timer
+ when the value in TC_RC is reached */
+ writel(AT91_TC_CMR_TCCLKS_CLOCK1 | AT91_TC_CMR_CPCTRG, &tc->tc[0].cmr);
+
+ writel(0xFFFFFFFF, &tc->tc[0].idr); /* disable interupts */
+ writel(TIMER_LOAD_VAL, &tc->tc[0].rc);
+
+ writel(AT91_TC_CCR_SWTRG | AT91_TC_CCR_CLKEN, &tc->tc[0].ccr);
+ gd->lastinc = 0;
+ gd->tbl = 0;
+
+ return 0;
+}
+
+/*
+ * timer without interrupts
+ */
+
+void reset_timer(void)
+{
+ reset_timer_masked();
+}
+
+ulong get_timer(ulong base)
+{
+ return get_timer_masked() - base;
+}
+
+void set_timer(ulong t)
+{
+ gd->tbl = t;
+}
+
+void __udelay(unsigned long usec)
+{
+ udelay_masked(usec);
+}
+
+void reset_timer_masked(void)
+{
+ /* reset time */
+ at91_tc_t *tc = (at91_tc_t *) AT91_TC_BASE;
+ gd->lastinc = readl(&tc->tc[0].cv) & 0x0000ffff;
+ gd->tbl = 0;
+}
+
+ulong get_timer_raw(void)
+{
+ at91_tc_t *tc = (at91_tc_t *) AT91_TC_BASE;
+ u32 now;
+
+ now = readl(&tc->tc[0].cv) & 0x0000ffff;
+
+ if (now >= gd->lastinc) {
+ /* normal mode */
+ gd->tbl += now - gd->lastinc;
+ } else {
+ /* we have an overflow ... */
+ gd->tbl += now + TIMER_LOAD_VAL - gd->lastinc;
+ }
+ gd->lastinc = now;
+
+ return gd->tbl;
+}
+
+ulong get_timer_masked(void)
+{
+ return get_timer_raw()/TIMER_LOAD_VAL;
+}
+
+void udelay_masked(unsigned long usec)
+{
+ u32 tmo;
+ u32 endtime;
+ signed long diff;
+
+ tmo = CONFIG_SYS_HZ_CLOCK / 1000;
+ tmo *= usec;
+ tmo /= 1000;
+
+ endtime = get_timer_raw() + tmo;
+
+ do {
+ u32 now = get_timer_raw();
+ diff = endtime - now;
+ } while (diff >= 0);
+}
+
+/*
+ * This function is derived from PowerPC code (read timebase as long long).
+ * On ARM it just returns the timer value.
+ */
+unsigned long long get_ticks(void)
+{
+ return get_timer(0);
+}
+
+/*
+ * This function is derived from PowerPC code (timebase clock frequency).
+ * On ARM it returns the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+ return CONFIG_SYS_HZ;
+}