From 18a8bd949d6adb311ea816125ff65050df1f3f6e Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sun, 15 Jul 2007 23:37:59 -0700 Subject: serial: convert early_uart to earlycon for 8250 Beacuse SERIAL_PORT_DFNS is removed from include/asm-i386/serial.h and include/asm-x86_64/serial.h. the serial8250_ports need to be probed late in serial initializing stage. the console_init=>serial8250_console_init=> register_console=>serial8250_console_setup will return -ENDEV, and console ttyS0 can not be enabled at that time. need to wait till uart_add_one_port in drivers/serial/serial_core.c to call register_console to get console ttyS0. that is too late. Make early_uart to use early_param, so uart console can be used earlier. Make it to be bootconsole with CON_BOOT flag, so can use console handover feature. and it will switch to corresponding normal serial console automatically. new command line will be: console=uart8250,io,0x3f8,9600n8 console=uart8250,mmio,0xff5e0000,115200n8 or earlycon=uart8250,io,0x3f8,9600n8 earlycon=uart8250,mmio,0xff5e0000,115200n8 it will print in very early stage: Early serial console at I/O port 0x3f8 (options '9600n8') console [uart0] enabled later for console it will print: console handover: boot [uart0] -> real [ttyS0] Signed-off-by: Cc: Andi Kleen Cc: Bjorn Helgaas Cc: Russell King Cc: Gerd Hoffmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/console.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux/console.h') diff --git a/include/linux/console.h b/include/linux/console.h index 62ef6e11d0d2..c44d3dfde7a5 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -99,6 +99,7 @@ struct console { struct tty_driver *(*device)(struct console *, int *); void (*unblank)(void); int (*setup)(struct console *, char *); + int (*early_setup)(void); short flags; short index; int cflag; @@ -107,6 +108,7 @@ struct console { }; extern int add_preferred_console(char *name, int idx, char *options); +extern int update_console_cmdline(char *name, int idx, char *name_new, int idx_new, char *options); extern void register_console(struct console *); extern int unregister_console(struct console *); extern struct console *console_drivers; -- cgit v1.2.1