[SeaBIOS] [PATCH 3/3] acpi: revert d9f5cdbdf (DSDT: Fix HPET _CRS Method)
Gabriel L. Somlo
gsomlo at gmail.com
Thu Dec 6 20:11:26 CET 2012
On Thu, Dec 06, 2012 at 06:10:46PM +0100, Alexander Graf wrote:
> > If I could figure out how to write a reliable _STA method for the SMC,
> > that would detect whether or not it was supplied as "-device applesmc"
> > on the qemu command line, I think we might be on to something...
> You should be able to poke fw_cfg in the _STA method. The machine file could search its bus on init (or on machine create notify) and populate a fw_cfg variable to indicate whether it found an applesmc.
So the fw_cfg looks like this in 'info qtree':
dev: fw_cfg, id ""
ctl_iobase = 0x510
data_iobase = 0x511
I'm confused by the mmio values (start at the very top of memory, go
for one or two bytes from there ?)
I also found this patch by Gerd, which doesn't seem to have made it
That patch suggests that I could just write stuff to 0x510 and read
from 0x511, and if I get it "right" the values I read will end up
making sense :)
Can anyone can point me to an example of how to interact with fw_cfg ?
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