Hard Reset of IXP1200 over PCI?

I'd like to be able to perform a hard reset of the IXP1200 over the PCI bus. Most of the documentation seems to indicate that I cannot do this. However, the IXP1200 Programmer's Reference Manual seems to indicate that it might be possible (but not allowed). Section 4.7.13 IXP1200_RESET indicates that the IXP1200_RESET register can be read and written from offset 0x7C. However, the paragraph directly above says that "PCI devices must not write to this register." What happens if I do? (I assume that the IXP1200 will reset and clear the PCI registers including the BAR set by the host machine. If I promise to put the board back in the same place in the PCI memory map, will everything be OK?) Scott