attached is a patch to enable mmconf access on RS690.
This patch is required for the upcoming Siemens sitemp mainboard.

1. Overwrite read resources in src/southbridge/amd/rs690/ht.c
   a. disable and hide BAR3 so pci_get_resource() doesn't touch.
   b. add an mmconf resource

2. Overwrite set_resources so that it:
   a. writes the mmconf resource base to the BAR3
   b. disable writes and hide BAR3
   c. find a not assigned resource in the K8 mmio and
      setup base and limit with flag nonposted
3. Add the resource as reserved in add_mainboard_resources()
4. in the mainboard's acpi_tables.c
   a. pass the mmconf base to the dsdt. 
   b. create a ACPI mcfg table

I've testet with Linux 2.6.12, Linux 2.6.26 and Windows XP SP3 + ATI X1200 driver, 
Linux 2.6.26 comes up with the following messages:
[    0.232014] PCI: MCFG configuration 0: base e0000000 segment 0 buses 0 - 31
[    0.232014] PCI: MCFG area at e0000000 reserved in E820
[    0.232014] PCI: Using MMCONFIG at e0000000 - e1ffffff
[    0.232014] PCI: Using configuration type 1 for base access

lspci -xxxx shows me 4Kb ext config space for some devices.

Can somebody please comment on the patch ? Would be nice !

Signed-off-by: Josef Kellermann <seppk@arcor.de>