Commit 70b0d22d authored by Yinghai Lu's avatar Yinghai Lu Committed by H. Peter Anvin
Browse files

x86, setup: Only set early_serial_base after port is initialized 



putchar is using early_serial_base to check if port is initialized.

So we only assign it after early_serial_init() is called,
in case we need use VGA to debug early serial console.

Also add display for port addr and baud.

-v2: update to current tip

Acked-by: default avatarPekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C3E0171.6050008@kernel.org>
Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
parent ce0aa5dd

arch/x86/boot/tty.c

+33 −30
Original line number Diff line number Diff line
@@ -152,35 +152,40 @@ int getchar_timeout(void) 
	return 0;		/* Timeout! */

}



static void early_serial_init(int baud)

static void early_serial_init(int port, int baud)

{

	unsigned char c;

	unsigned divisor;



	outb(0x3, early_serial_base + LCR);	/* 8n1 */

	outb(0, early_serial_base + IER);	/* no interrupt */

	outb(0, early_serial_base + FCR);	/* no fifo */

	outb(0x3, early_serial_base + MCR);	/* DTR + RTS */

	outb(0x3, port + LCR);	/* 8n1 */

	outb(0, port + IER);	/* no interrupt */

	outb(0, port + FCR);	/* no fifo */

	outb(0x3, port + MCR);	/* DTR + RTS */



	divisor	= 115200 / baud;

	c = inb(early_serial_base + LCR);

	outb(c | DLAB, early_serial_base + LCR);

	outb(divisor & 0xff, early_serial_base + DLL);

	outb((divisor >> 8) & 0xff, early_serial_base + DLH);

	outb(c & ~DLAB, early_serial_base + LCR);

	c = inb(port + LCR);

	outb(c | DLAB, port + LCR);

	outb(divisor & 0xff, port + DLL);

	outb((divisor >> 8) & 0xff, port + DLH);

	outb(c & ~DLAB, port + LCR);



	early_serial_base = port;



	printf("Early serial console at I/O port 0x%x baud: %d\n", port, baud);

}



static int parse_earlyprintk(void)

static void parse_earlyprintk(void)

{

	int baud = DEFAULT_BAUD;

	char arg[32];

	int pos = 0;

	int port = 0;



	if (cmdline_find_option("earlyprintk", arg, sizeof arg) > 0) {

		char *e;



		if (!strncmp(arg, "serial", 6)) {

			early_serial_base = DEFAULT_SERIAL_PORT;

			port = DEFAULT_SERIAL_PORT;

			pos += 6;

		}
@@ -189,15 +194,15 @@ static int parse_earlyprintk(void) 


		if (!strncmp(arg, "ttyS", 4)) {

			static const int bases[] = { 0x3f8, 0x2f8 };

			int port = 0;

			int idx = 0;



			if (!strncmp(arg + pos, "ttyS", 4))

				pos += 4;



			if (arg[pos++] == '1')

				port = 1;

				idx = 1;



			early_serial_base = bases[port];

			port = bases[idx];

		}



		if (arg[pos] == ',')
@@ -208,7 +213,8 @@ static int parse_earlyprintk(void) 
			baud = DEFAULT_BAUD;

	}



	return baud;

	if (port)

		early_serial_init(port, baud);

}



#define BASE_BAUD (1843200/16)
@@ -227,44 +233,41 @@ static unsigned int probe_baud(int port) 
	return BASE_BAUD / quot;

}



static int parse_console_uart8250(void)

static void parse_console_uart8250(void)

{

	char optstr[64], *options;

	int baud = DEFAULT_BAUD;

	int port = 0;



	/*

	 * console=uart8250,io,0x3f8,115200n8

	 * need to make sure it is last one console !

	 */

	if (cmdline_find_option("console", optstr, sizeof optstr) <= 0)

		return baud;

		return;



	options = optstr;



	if (!strncmp(options, "uart8250,io,", 12))

		early_serial_base = simple_strtoull(options + 12, &options, 0);

		port = simple_strtoull(options + 12, &options, 0);

	else if (!strncmp(options, "uart,io,", 8))

		early_serial_base = simple_strtoull(options + 8, &options, 0);

		port = simple_strtoull(options + 8, &options, 0);

	else

		return baud;

		return;



	if (options && (options[0] == ','))

		baud = simple_strtoull(options + 1, &options, 0);

	else

		baud = probe_baud(early_serial_base);

		baud = probe_baud(port);



	return baud;

	if (port)

		early_serial_init(port, baud);

}



void console_init(void)

{

	int baud;



	baud = parse_earlyprintk();

	parse_earlyprintk();



	if (!early_serial_base)

		baud = parse_console_uart8250();



	if (early_serial_base != 0)

		early_serial_init(baud);

		parse_console_uart8250();

}

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