[LinuxBIOS] Problems Setting The Opteron Address Map (resourcemap.c)

Stefan Reinauer stepan at openbios.org
Fri Mar 18 15:54:41 CET 2005

* Jeff Stevens <jsteve17 at yahoo.com> [050318 15:27]:
> If there is
> a good document to help one setup the address map,
> other than the "AMD BIOS and Kernel Developer's
> Guide", please let me know.

I'm afraid there is not.
> 1. Does the DRAM map section pertain to the DDR SDRAM,
> or is there an ability on the Opteron (as on some
> other PPC processors I have dealt with) to hang
> standard DRAM off of the local bus of the processor? 
> If this is for DDR SDRAM, if I leave them all
> disabled, do these get configured later when the BIOS
> reads the SPD PROM for the DDR?  Or do I have to
> configure a Window for each processor's maximum
> allowable DDR SDRAM?

They are supposed to be filled out by the SPDROM setup 
code of LinuxBIOS. Leave them untouched.
> 2. It seems that the Memory Mapped I/O section is
> mainly to map the AMD 8111 and 8131s IO-APIC address
> ranges (which seem to be 64KB in size).  Is this
> correct, and is there anything else that should go
> there (maybe PCI space)?
AFAIK this should stay untouched as well to be set up 
by LinuxBIOS.

> 3. The PCI I/O section is my main problem.  I haven't
> dealt with PCI too much in depth.  I don't understand
> how it uses only 13 bits for the PCI I/O Base and
> Limit addresses?  I thought that you need a 32-bit
> address?  

It is the upper bit range, so you automatically set these 
given a certain alignment.

> I/O base address is!  The only examples in the
> LinuxBIOS tree have the AMD 8111 & 8131s hanging off
> of one CPU, and therefor just steer all of the address
> range to that HT link.

No, have a look at the island/aruma board. It has 8131 
hanging off every single CPU.


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