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authorwdenk <wdenk>2004-08-01 22:48:16 +0000
committerwdenk <wdenk>2004-08-01 22:48:16 +0000
commit281e00a3be453a169d854f824a460359d10f92bb (patch)
tree43dab398f1d6f601bb44df108427f7e0c611d68d /cpu/arm920t/s3c24x0_interrupts.c
parentcfca5e604d5692f081cc1a9185ca5dc6dc77599d (diff)
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* Code cleanup
* Patch by Sascha Hauer, 28 Jun: - add generic support for Motorola i.MX architecture - add support for mx1ads, mx1fs2 and scb9328 boards * Patches by Marc Leeman, 23 Jul 2004: - Add define for the PCI/Memory Buffer Configuration Register - corrected comments in cpu/mpc824x/cpu_init.c * Add support for multiple serial interfaces (for example to allow modem dial-in / dial-out)
Diffstat (limited to 'cpu/arm920t/s3c24x0_interrupts.c')
-rw-r--r--cpu/arm920t/s3c24x0_interrupts.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/cpu/arm920t/s3c24x0_interrupts.c b/cpu/arm920t/s3c24x0_interrupts.c
new file mode 100644
index 0000000..92298b0
--- /dev/null
+++ b/cpu/arm920t/s3c24x0_interrupts.c
@@ -0,0 +1,180 @@
+/*
+ * (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>
+ *
+ * (C) Copyright 2002
+ * Gary Jennejohn, DENX Software Engineering, <gj@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>
+#if defined(CONFIG_S3C2400) || defined (CONFIG_S3C2410) || defined (CONFIG_TRAB)
+
+#include <arm920t.h>
+#if defined(CONFIG_S3C2400)
+#include <s3c2400.h>
+#elif defined(CONFIG_S3C2410)
+#include <s3c2410.h>
+#endif
+
+extern void reset_cpu(ulong addr);
+int timer_load_val = 0;
+
+/* macro to read the 16 bit timer */
+static inline ulong READ_TIMER(void)
+{
+ S3C24X0_TIMERS * const timers = S3C24X0_GetBase_TIMERS();
+
+ return (timers->TCNTO4 & 0xffff);
+}
+
+static ulong timestamp;
+static ulong lastdec;
+
+int interrupt_init (void)
+{
+ S3C24X0_TIMERS * const timers = S3C24X0_GetBase_TIMERS();
+
+ /* use PWM Timer 4 because it has no output */
+ /* prescaler for Timer 4 is 16 */
+ timers->TCFG0 = 0x0f00;
+ if (timer_load_val == 0)
+ {
+ /*
+ * for 10 ms clock period @ PCLK with 4 bit divider = 1/2
+ * (default) and prescaler = 16. Should be 10390
+ * @33.25MHz and 15625 @ 50 MHz
+ */
+ timer_load_val = get_PCLK()/(2 * 16 * 100);
+ }
+ /* load value for 10 ms timeout */
+ lastdec = timers->TCNTB4 = timer_load_val;
+ /* auto load, manual update of Timer 4 */
+ timers->TCON = (timers->TCON & ~0x0700000) | 0x600000;
+ /* auto load, start Timer 4 */
+ timers->TCON = (timers->TCON & ~0x0700000) | 0x500000;
+ timestamp = 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)
+{
+ timestamp = t;
+}
+
+void udelay (unsigned long usec)
+{
+ ulong tmo;
+ ulong start = get_timer(0);
+
+ tmo = usec / 1000;
+ tmo *= (timer_load_val * 100);
+ tmo /= 1000;
+
+ while ((ulong)(get_timer_masked () - start) < tmo)
+ /*NOP*/;
+}
+
+void reset_timer_masked (void)
+{
+ /* reset time */
+ lastdec = READ_TIMER();
+ timestamp = 0;
+}
+
+ulong get_timer_masked (void)
+{
+ ulong now = READ_TIMER();
+
+ if (lastdec >= now) {
+ /* normal mode */
+ timestamp += lastdec - now;
+ } else {
+ /* we have an overflow ... */
+ timestamp += lastdec + timer_load_val - now;
+ }
+ lastdec = now;
+
+ return timestamp;
+}
+
+void udelay_masked (unsigned long usec)
+{
+ ulong tmo;
+
+ tmo = usec / 1000;
+ tmo *= (timer_load_val * 100);
+ tmo /= 1000;
+
+ reset_timer_masked ();
+
+ while (get_timer_masked () < tmo)
+ /*NOP*/;
+}
+
+/*
+ * 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)
+{
+ ulong tbclk;
+
+#if defined(CONFIG_SMDK2400) || defined(CONFIG_TRAB)
+ tbclk = timer_load_val * 100;
+#elif defined(CONFIG_SMDK2410) || defined(CONFIG_VCMA9)
+ tbclk = CFG_HZ;
+#else
+# error "tbclk not configured"
+#endif
+
+ return tbclk;
+}
+
+#endif /* defined(CONFIG_S3C2400) || defined (CONFIG_S3C2410) || defined (CONFIG_TRAB) */