[coreboot] RTC

Jordan Crouse jordan.crouse at amd.com
Wed Apr 16 21:55:33 CEST 2008

I'm puttering about in libpayload doing silly things with the real time
clock, and it occurred to me to figure out if coreboot knows how to set
the clock to a sane value if CMOS had been cleared or something similar.

I looked in v2 at pc80/mc146818rtc.c, and the code that writes to the
clock appears to be #if 0ed out.  I couldn't find any where else where
the clock would be set.  The same thing is disabled on v3.   According
to svn blame, it has been like that ever since ebiderm checked in v2.

is there an interesting story as to why this is disabled?  IMHO, we should
be setting the clock to a sane value if it is determined to be bad,
especially since we'll probably have some payloads soon that will care
what time it is.   Not so much that they need to be accurate down to the
microsecond, but more that I want to be sure that if I read the clock,
its not bogus.

Jordan Crouse
Systems Software Development Engineer 
Advanced Micro Devices, Inc.

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