a quick status on how QEMU has evolved regarding this topic.
We have merged :
a09410ed1fb8 ("target/ppc: Remove the software TLB model of 7450 CPUs")
and switched MMU model to POWERPC_MMU_32B in :
1da666cd8e79 ("target/ppc: Disable software TLB for the 7450 family")
With the two patches of this series, we can boot the latest linux on all 7450 CPUs. With an extra small fix on the CPU table, 7448 boots.
A small correction, we only need OpenBIOS to include patch 2: "ppc: Add PVRs for the MPC7450 family".
Yep we don't need the vectors anymore. But I think I remember Mark saying it would be nice to keep the implementation.
I have an extra patch for 7448 tough.