From 70b0d22d581a5deef7b2876b0c3774635b8d846c Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Wed, 14 Jul 2010 11:26:57 -0700 Subject: [PATCH] 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 Signed-off-by: Yinghai Lu LKML-Reference: <4C3E0171.6050008@kernel.org> Signed-off-by: H. Peter Anvin --- arch/x86/boot/tty.c | 63 ++++++++++++++++++++++++--------------------- 1 file changed, 33 insertions(+), 30 deletions(-) diff --git a/arch/x86/boot/tty.c b/arch/x86/boot/tty.c index f6d52e65f97a..ff4b27a0fc5e 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(); } -- 2.20.1