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-rw-r--r--src/pc80/i8254.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/src/pc80/i8254.c b/src/pc80/i8254.c
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+++ b/src/pc80/i8254.c
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+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2009 coresystems GmbH
+ *
+ * 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; version 2 of the License.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <arch/io.h>
+#include <pc80/i8254.h>
+#include <console/console.h>
+
+/* Initialize i8254 timers */
+
+void setup_i8254(void)
+{
+ /* Timer 0 (taken from biosemu) */
+ outb(TIMER0_SEL|WORD_ACCESS|MODE3|BINARY_COUNT, TIMER_MODE_PORT);
+ outb(0x00, TIMER0_PORT);
+ outb(0x00, TIMER0_PORT);
+
+ /* Timer 1 */
+ outb(TIMER1_SEL|LOBYTE_ACCESS|MODE3|BINARY_COUNT, TIMER_MODE_PORT);
+ outb(0x12, TIMER1_PORT);
+}
+
+#ifdef CONFIG_UDELAY_TIMER2
+static void load_timer2(unsigned int ticks)
+{
+ /* Set up the timer gate, turn off the speaker */
+ outb((inb(PPC_PORTB) & ~PPCB_SPKR) | PPCB_T2GATE, PPC_PORTB);
+ outb(TIMER2_SEL|WORD_ACCESS|MODE0|BINARY_COUNT, TIMER_MODE_PORT);
+ outb(ticks & 0xFF, TIMER2_PORT);
+ outb(ticks >> 8, TIMER2_PORT);
+}
+
+
+void udelay(int usecs)
+{
+ load_timer2((usecs*TICKS_PER_MS)/1000);
+ while ((inb(PPC_PORTB) & PPCB_T2OUT) == 0)
+ ;
+}
+#endif