rewrite the serial port handling to manipulate the hardware directly

rather than relying on calls into the bios to work.

this is a result of me getting pissed off with solaris and linux
being able to cope the serial bios redirection on dracs, iloms, and
ilos. trying to do the same thing with openbsds boot loader caused
weird behaviour like machine hangs or no visible output. talking
to the serial chips directly is more reliable.

tested by many

ok sthen@ deraadt@

1 files changed, 29 insertions, 31 deletions

diff --git a/sys/arch/amd64/stand/libsa/bioscons.c b/sys/arch/amd64/stand/libsa/bioscons.c
index b438a15a2af..d414a4f47ff 100644
--- a/sys/arch/amd64/stand/libsa/bioscons.c
+++ b/sys/arch/amd64/stand/libsa/bioscons.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bioscons.c,v 1.4 2008/01/23 16:37:56 jsing Exp $	*/
+/*	$OpenBSD: bioscons.c,v 1.5 2008/04/20 01:46:35 dlg Exp $	*/
 
 /*
  * Copyright (c) 1997-1999 Michael Shalayeff
@@ -131,37 +131,40 @@ com_probe(struct consdev *cn)
 	}
 }
 
+int com_speed = -1;  /* default speed is 9600 baud */
+
 void
 com_init(struct consdev *cn)
 {
-	register int unit = minor(cn->cn_dev);
-
-	/* let bios do necessary init first, 9600-N-1 */
-	__asm __volatile(DOINT(0x14) : : "a" (0xe3), "d" (unit) :
-	    "%ecx", "cc" );
+	int port = comports[minor(cn->cn_dev)];
+
+	outb(port + com_ier, 0);
+	if (com_speed == -1)
+		comspeed(cn->cn_dev, 9600);
+	outb(port + com_mcr, MCR_DTR | MCR_RTS);
+	outb(port + com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST |
+	    FIFO_TRIGGER_1);
+
+	/* drain the input buffer */
+	while (inb(port + com_lsr) & LSR_RXRDY)
+		(void)inb(port + com_data);
 }
 
 int
 com_getc(dev_t dev)
 {
-	register int rv;
+	int port = comports[minor(dev & 0x7f)];
 
-	if (dev & 0x80) {
-		__asm __volatile(DOINT(0x14) : "=a" (rv) :
-		    "0" (0x300), "d" (minor(dev&0x7f)) : "%ecx", "cc" );
-		return ((rv & 0x100) == 0x100);
-	}
+	if (dev & 0x80)
+		return (inb(port + com_lsr) & LSR_RXRDY);
 
-	do
-		__asm __volatile(DOINT(0x14) : "=a" (rv) :
-		    "0" (0x200), "d" (minor(dev)) : "%ecx", "cc" );
-	while (rv & 0x8000);
+	while ((inb(port + com_lsr) & LSR_RXRDY) == 0)
+		;
 
-	return (rv & 0xff);
+	return (inb(port + com_data) & 0xff);
 }
 
 /* call with sp == 0 to query the current speed */
-int com_speed = 9600;  /* default speed is 9600 baud */
 int
 comspeed(dev_t dev, int sp)
 {
@@ -195,7 +198,8 @@ comspeed(dev_t dev, int sp)
 		return -1;
 #undef  divrnd
 
-	if (cn_tab && cn_tab->cn_dev == dev && com_speed != sp) {
+	if (com_speed != -1 && cn_tab && cn_tab->cn_dev == dev &&
+	    com_speed != sp) {
 		printf("com%d: changing speed to %d baud in 5 seconds, "
 		    "change your terminal to match!\n\a",
 		    minor(dev), sp);
@@ -206,7 +210,8 @@ comspeed(dev_t dev, int sp)
 	outb(comports[minor(dev)] + com_dlbl, newsp);
 	outb(comports[minor(dev)] + com_dlbh, newsp>>8);
 	outb(comports[minor(dev)] + com_cfcr, LCR_8BITS);
-	printf("\ncom%d: %d baud\n", minor(dev), sp);
+	if (com_speed != -1)
+		printf("\ncom%d: %d baud\n", minor(dev), sp);
 
 	newsp = com_speed;
 	com_speed = sp;
@@ -216,18 +221,11 @@ comspeed(dev_t dev, int sp)
 void
 com_putc(dev_t dev, int c)
 {
-	register int rv;
-
-	dev = minor(dev) & 0x7f;
+	int port = comports[minor(dev)];
 
-	/* check online (DSR) */
-	__asm __volatile(DOINT(0x14) : "=a" (rv) :
-	    "0" (0x300), "d" (dev) : "%ecx", "cc" );
-	if ( !(rv & 0x20) )
-		return;
+	while ((inb(port + com_lsr) & LSR_TXRDY) == 0)
+		;
 
-	/* send character */
-	__asm __volatile(DOINT(0x14) : "=a" (rv) :
-	    "0" (c | 0x100), "d" (dev) : "%ecx", "cc" );
+	outb(port + com_data, c);
 }