From f4ed2877b16e8146427306aea8819adac5c88374 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Mon, 2 Aug 2010 02:17:31 -0700 Subject: x86, setup: reorganize the early console setup Separate early_serial_console from tty.c This allows for reuse of early_serial_console.c/string.c/printf.c/cmdline.c in boot/compressed/. -v2: according to hpa, don't include string.c etc -v3: compressed/misc.c must have early_serial_base as static, so move it back to tty.c for setup code Signed-off-by: Yinghai Lu LKML-Reference: <4C568D2B.205@kernel.org> Signed-off-by: H. Peter Anvin --- arch/x86/boot/tty.c | 136 +--------------------------------------------------- 1 file changed, 1 insertion(+), 135 deletions(-) (limited to 'arch/x86/boot/tty.c') diff --git a/arch/x86/boot/tty.c b/arch/x86/boot/tty.c index ff4b27a0fc5e..def2451f46ae 100644 --- a/arch/x86/boot/tty.c +++ b/arch/x86/boot/tty.c @@ -15,27 +15,12 @@ #include "boot.h" -#define DEFAULT_SERIAL_PORT 0x3f8 /* ttyS0 */ - -static int early_serial_base; +int early_serial_base; #define XMTRDY 0x20 -#define DLAB 0x80 - #define TXR 0 /* Transmit register (WRITE) */ -#define RXR 0 /* Receive register (READ) */ -#define IER 1 /* Interrupt Enable */ -#define IIR 2 /* Interrupt ID */ -#define FCR 2 /* FIFO control */ -#define LCR 3 /* Line control */ -#define MCR 4 /* Modem control */ #define LSR 5 /* Line Status */ -#define MSR 6 /* Modem Status */ -#define DLL 0 /* Divisor Latch Low */ -#define DLH 1 /* Divisor latch High */ - -#define DEFAULT_BAUD 9600 /* * These functions are in .inittext so they can be used to signal @@ -152,122 +137,3 @@ int getchar_timeout(void) return 0; /* Timeout! */ } -static void early_serial_init(int port, int baud) -{ - unsigned char c; - unsigned divisor; - - 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(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 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)) { - port = DEFAULT_SERIAL_PORT; - pos += 6; - } - - if (arg[pos] == ',') - pos++; - - if (!strncmp(arg, "ttyS", 4)) { - static const int bases[] = { 0x3f8, 0x2f8 }; - int idx = 0; - - if (!strncmp(arg + pos, "ttyS", 4)) - pos += 4; - - if (arg[pos++] == '1') - idx = 1; - - port = bases[idx]; - } - - if (arg[pos] == ',') - pos++; - - baud = simple_strtoull(arg + pos, &e, 0); - if (baud == 0 || arg + pos == e) - baud = DEFAULT_BAUD; - } - - if (port) - early_serial_init(port, baud); -} - -#define BASE_BAUD (1843200/16) -static unsigned int probe_baud(int port) -{ - unsigned char lcr, dll, dlh; - unsigned int quot; - - lcr = inb(port + LCR); - outb(lcr | DLAB, port + LCR); - dll = inb(port + DLL); - dlh = inb(port + DLH); - outb(lcr, port + LCR); - quot = (dlh << 8) | dll; - - return BASE_BAUD / quot; -} - -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; - - options = optstr; - - if (!strncmp(options, "uart8250,io,", 12)) - port = simple_strtoull(options + 12, &options, 0); - else if (!strncmp(options, "uart,io,", 8)) - port = simple_strtoull(options + 8, &options, 0); - else - return; - - if (options && (options[0] == ',')) - baud = simple_strtoull(options + 1, &options, 0); - else - baud = probe_baud(port); - - if (port) - early_serial_init(port, baud); -} - -void console_init(void) -{ - parse_earlyprintk(); - - if (!early_serial_base) - parse_console_uart8250(); -} -- cgit v1.2.3