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authorYinghai Lu <yinghai@kernel.org>2010-07-14 18:26:57 (GMT)
committerH. Peter Anvin <hpa@linux.intel.com>2010-07-14 19:07:16 (GMT)
commit70b0d22d581a5deef7b2876b0c3774635b8d846c (patch)
tree7ec83deb42a6b9bcbbc1517298a77cd380321af6 /arch/x86/boot
parentce0aa5dd20e44372f9617dd67c984f41fcdbed88 (diff)
downloadlinux-70b0d22d581a5deef7b2876b0c3774635b8d846c.tar.xz
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: 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>
Diffstat (limited to 'arch/x86/boot')
-rw-r--r--arch/x86/boot/tty.c63
1 files changed, 33 insertions, 30 deletions
diff --git a/arch/x86/boot/tty.c b/arch/x86/boot/tty.c
index f6d52e6..ff4b27a 100644
--- a/arch/x86/boot/tty.c
+++ b/arch/x86/boot/tty.c
@@ -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();
}