Rockchip rk27xx port initial commit. This is still work in progress.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@29935 a1c6a512-1295-4272-9138-f99709370657

firmware/target/arm/rk27xx/kernel-rk27xx.c

@@ -0,0 +1,54 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2011 by Marcin Bukat
+ *
+ * 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"
+
+/*  rockchip rk27xx driver for the kernel timer */
+
+/* sys timer ISR */
+void INT_TIMER0(void)
+{
+    /* clear interrupt */
+    TMR0CON &= ~0x04;
+
+    call_tick_tasks();  /* Run through the list of tick tasks */
+}
+
+/* this assumes 50MHz APB bus frequency */
+void tick_start(unsigned int interval_in_ms)
+{
+    unsigned int cycles = 50000 * interval_in_ms;
+    
+    /* enable timer clock */
+    SCU_CLKCFG &= (1<<28);
+    
+    /* configure timer0 */
+    TMR0LR = cycles;
+    TMR0CON = (1<<8) | (1<<7) | (1<<1); /* periodic, 1/1, interrupt enable */
+
+    /* unmask timer0 interrupt */
+    INTC_IMR |= 0x04;
+
+    /* enable timer0 interrupt */
+    INTC_IECR |= 0x04;
+}
+