MPC8270 PCI Bridge Configuration Register offset 0x40 and 0x98

[reedy]

While making modifications to legacy software we have found writes to reserved/undocumented registers.  Maybe these are from an early datasheet or errata?

Both writes are to the host PCI configuration space (bus=0, dev=0, fxn=0)

// PCI Bridge Option

0x40 = 0x00000004;

// PCI PIMOSA

0x98 = 0xC0000003;

Does anyone recognize what these register writes are doing?

Thanks,

[Bulat · Accepted solution]

Those registers are definitely not from the MPC8270 PCI configuration space. If your software was really written for the MPC8270, you should remove those writes.

Regards,

Bulat