diff options
| author | Yinghai Lu <Yinghai.Lu@Sun.COM> | 2007-07-15 23:37:59 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-16 09:05:35 -0700 |
| commit | 18a8bd949d6adb311ea816125ff65050df1f3f6e (patch) | |
| tree | 4365db908430747a5c08cacdb4354577b7bfead7 /kernel | |
| parent | b1c931e39327ef121797927d4b3198d370e75b9b (diff) | |
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: <yinghai.lu@sun.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Gerd Hoffmann <kraxel@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/printk.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/kernel/printk.c b/kernel/printk.c index 7ce9a8c1331..f46cc6dff46 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -726,6 +726,25 @@ int __init add_preferred_console(char *name, int idx, char *options) return 0; } +int __init update_console_cmdline(char *name, int idx, char *name_new, int idx_new, char *options) +{ + struct console_cmdline *c; + int i; + + for (i = 0; i < MAX_CMDLINECONSOLES && console_cmdline[i].name[0]; i++) + if (strcmp(console_cmdline[i].name, name) == 0 && + console_cmdline[i].index == idx) { + c = &console_cmdline[i]; + memcpy(c->name, name_new, sizeof(c->name)); + c->name[sizeof(c->name) - 1] = 0; + c->options = options; + c->index = idx_new; + return i; + } + /* not found */ + return -1; +} + #ifndef CONFIG_DISABLE_CONSOLE_SUSPEND /** * suspend_console - suspend the console subsystem @@ -942,6 +961,9 @@ void register_console(struct console *console) if (preferred_console < 0 || bootconsole || !console_drivers) preferred_console = selected_console; + if (console->early_setup) + console->early_setup(); + /* * See if we want to use this console driver. If we * didn't select a console we take the first one |