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x86, setup: Only set early_serial_base after port is initialized

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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: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C3E0171.6050008@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This commit is contained in:
Yinghai Lu 2010-07-14 11:26:57 -07:00 committed by H. Peter Anvin
parent ce0aa5dd20
commit 70b0d22d58
1 changed files with 33 additions and 30 deletions
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63
arch/x86/boot/tty.c
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@ -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();
}