[coreboot] Where does printk(DEBUG, "msg") go after booting?
scott at notabs.org
Tue Nov 30 18:35:46 CET 2010
From: coreboot-bounces at coreboot.org [mailto:coreboot-bounces at coreboot.org] On Behalf Of Patrick Georgi
Sent: Tuesday, November 30, 2010 11:26 AM
To: coreboot at coreboot.org
Subject: Re: [coreboot] Where does printk(DEBUG, "msg") go after booting?
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Am 30.11.2010 18:16, schrieb Fengwei Zhang:
> I understand the printk(DEBUG, "msg") statement will print out msg on
> the serial port when booting. How about after booting? Where does
> printk(DEBUG, "msg") go after booting?
]"After booting" the only component that might still be active (and thus
]able to run our printk) would be SMM. That code shares the same printing
]routines, so it prints on serial, too.
One thing to watch for is the OS changing the baud rate. I notice this with
coreboot+seabios and DOS after CtrlAltDel. DOS sets the baud rate to 2400.
The serial output is still present, but the baud rate must be changed to see it.
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