- Unimplemented ASEs:
- MDMX
- SmartMIPS
- - DSP r1
- - DSP r2
+ - microMIPS DSP r1 & r2 encodings
- MT ASE only partially implemented and not functional
- Shadow register support only partially implemented,
lacks set switching on interrupt/exception.
Existing documentation is x86-centric.
- Reverse endianness bit not implemented
- The TLB emulation is very inefficient:
- Qemu's softmmu implements a x86-style MMU, with separate entries
+ QEMU's softmmu implements a x86-style MMU, with separate entries
for read/write/execute, a TLB index which is just a modulo of the
virtual address, and a set of TLBs for each user/kernel/supervisor
MMU mode.
up to 256 ASID tags as additional matching criterion (which roughly
equates to 256 MMU modes). It also has a global flag which causes
entries to match regardless of ASID.
- To cope with these differences, Qemu currently flushes the TLB at
+ To cope with these differences, QEMU currently flushes the TLB at
each ASID change. Using the MMU modes to implement ASIDs hinges on
implementing the global bit efficiently.
- save/restore of the CPU state is not implemented (see machine.c).