1 files changed, 79 insertions, 0 deletions

diff --git a/firmware/target/arm/s3c2440/kernel-s3c2440.c b/firmware/target/arm/s3c2440/kernel-s3c2440.c
new file mode 100644
index 0000000000..6cabc8dc81
--- /dev/null
+++ b/firmware/target/arm/s3c2440/kernel-s3c2440.c
@@ -0,0 +1,79 @@
+/***************************************************************************
+*             __________               __   ___.
+*   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+*   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+*   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+*   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+*                     \/            \/     \/    \/            \/
+* $Id$
+*
+* Copyright (C) 2007 by Michael Sevakis
+*
+* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+* KIND, either express or implied.
+*
+****************************************************************************/
+#include "config.h"
+#include "system.h"
+#include "kernel.h"
+#include "timer.h"
+#include "thread.h"
+
+void tick_start(unsigned int interval_in_ms)
+{
+    /*
+     * Based on default PCLK of 49.1568MHz - scaling chosen to give
+     * remainder-free result for tick interval of 10ms (100Hz)
+     * Timer input clock frequency =
+     *      fPCLK / {prescaler value+1} / {divider value}
+     * TIMER_FREQ = 49156800 / 2
+     * 146300 = TIMER_FREQ / 21 / 8
+     * 49156800 = 19*11*(7)*7*5*5*(3)*2*2*2*2*2*2
+     * 21 = 7*3
+     */
+
+    /* stop timer 4 */
+    TCON &= ~(1 << 20);
+    /* Set the count for timer 4 */
+    TCNTB4 = (TIMER_FREQ / TIMER234_PRESCALE / 8) * interval_in_ms / 1000;
+    /* Set the the prescaler value for timers 2,3, and 4 */
+    TCFG0 = (TCFG0 & ~0xff00) | ((TIMER234_PRESCALE-1) << 8);
+    /* DMA mode off, MUX4 = 1/16 */
+    TCFG1 = (TCFG1 & ~0xff0000) | 0x030000;
+    /* set manual bit */
+    TCON |= 1 << 21;
+    /* reset manual bit */
+    TCON &= ~(1 << 21);
+
+    /* interval mode */
+    TCON |= 1 << 22;
+    /* start timer 4 */
+    TCON |= (1 << 20);
+
+    /* timer 4 unmask interrupts */
+    INTMSK &= ~TIMER4_MASK;
+}
+
+#ifdef BOOTLOADER
+void tick_stop(void)
+{
+    s3c_regset32(&INTMSK, TIMER4_MASK);
+    TCON &= ~(1 << 20);
+    SRCPND = TIMER4_MASK;
+    INTPND = TIMER4_MASK;
+}
+#endif
+
+void TIMER4(void)
+{
+    /* Run through the list of tick tasks */
+    call_tick_tasks();
+
+    SRCPND = TIMER4_MASK;
+    INTPND = TIMER4_MASK;
+}