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authorYinghai Lu <yinghai@kernel.org>2010-08-02 13:17:31 +0400
committerH. Peter Anvin <hpa@linux.intel.com>2010-08-03 02:51:56 +0400
commitf4ed2877b16e8146427306aea8819adac5c88374 (patch)
tree9451d9e5bb300634b00c25bd0ab155a1854e4223 /arch/x86/boot/tty.c
parent22a57f5896df218356bae6203dfaf04bcfd6c88c (diff)
downloadlinux-f4ed2877b16e8146427306aea8819adac5c88374.tar.xz
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 <yinghai@kernel.org> LKML-Reference: <4C568D2B.205@kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/boot/tty.c')
-rw-r--r--arch/x86/boot/tty.c136
1 files changed, 1 insertions, 135 deletions
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();
-}