S5L8700: implement kernel timer

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21672 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 59 insertions, 0 deletions

diff --git a/firmware/target/arm/s5l8700/kernel-s5l8700.c b/firmware/target/arm/s5l8700/kernel-s5l8700.c
new file mode 100644
index 0000000000..b905ade0c1
--- /dev/null
+++ b/firmware/target/arm/s5l8700/kernel-s5l8700.c
@@ -0,0 +1,59 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright © 2009 Bertrik Sikken
+ *
+ * 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"
+
+/*  S5L8700 driver for the kernel timer
+
+    Timer B is configured as a 10 kHz timer (assuming PCLK = 100 MHz)
+ */
+
+void INT_TIMERB(void)
+{
+    /* clear interrupt */
+    TBCON = TBCON;
+
+    call_tick_tasks();  /* Run through the list of tick tasks */
+}
+
+void tick_start(unsigned int interval_in_ms)
+{
+    int cycles = 10 * interval_in_ms;
+    
+    /* enable timer clock */
+    PWRCON &= ~(1 << 4);
+    
+    /* configure timer for 10 kHz */
+    TBCMD = (1 << 1);   /* TB_CLR */
+    TBPRE = 625;        /* prescaler */
+    TBCON = (0 << 13) | /* TB_INT1_EN */
+            (1 << 12) | /* TB_INT0_EN */
+            (0 << 11) | /* TB_START */
+            (2 << 8) |  /* TB_CS = PCLK / 16 */
+            (0 << 4);   /* TB_MODE_SEL = interval mode */
+    TBDATA0 = cycles-1; /* set interval period */
+    TBCMD = (1 << 0);   /* TB_EN */
+
+    /* enable timer interrupt */
+    INTMSK |= (1 << 7);
+}
+