libpayload: The initial chunk of code writen by AMD

This is the initial chunk of code written by me and copyrighted
by AMD.  Includes everything but a few files that we pulled from
outside sources.

Signed-off-by: Jordan Crouse <jordan.crouse@amd.com>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@3170 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

payloads/libpayload/drivers/serial.c

@@ -0,0 +1,78 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2008 Advanced Micro Devices, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <libpayload.h>
+#include <sysinfo.h>
+
+#define IOBASE lib_sysinfo.ser_ioport
+
+#ifdef CONFIG_SERIAL_SET_SPEED
+#define DIVISOR (115200 / CONFIG_SERIAL_BAUD_RATE)
+#endif
+
+void serial_init(void)
+{	
+#ifdef CONFIG_SERIAL_SET_SPEED
+	unsigned char reg;
+
+	/* Disable interrupts */
+	outb(0, IOBASE + 0x01);
+
+	/* Assert RTS and DTR */
+	outb(3, IOBASE + 0x04);
+
+	/* Set the divisor latch */
+	reg = inb(IOBASE + 0x03);
+	outb(reg | 0x80, IOBASE + 0x03);
+
+	/* Write the divisor */
+	outb(DIVISOR & 0xFF, IOBASE);
+	outb(DIVISOR >> 8 & 0xFF, IOBASE + 1);
+
+	/* Restore the previous value of the divisor */
+	outb(reg &= ~0x80, IOBASE + 0x03);
+#endif
+}
+			
+void serial_putchar(unsigned char c)
+{
+	while((inb(IOBASE + 0x05) & 0x20) == 0);
+	outb(c, IOBASE);
+}
+
+int serial_havechar(void)
+{
+	return inb(IOBASE + 0x05) & 0x01;
+}
+
+int serial_getchar(void)
+{
+	while (!serial_havechar());
+	return (int) inb(IOBASE);
+}