Ralf Baechle (ralf@xxxxxxxxxxxxxx) writes: > I've posted updated Qemu patches on > > ftp://ftp.linux-mips.org/pub/linux/mips/qemu > http://www.linux-mips.org/wiki/index.php/Qemu > > Enhancements over last week's patches: > > o The count/compare interrupt will now properly be delivered. > o mfc0 will now return the proper value for the EXL and ERL flags > o eret will now consider the value of ERL and EXL. > o i8259 PIC is now properly cascaded to a CPU interrupt. > o An ISA NE2000 card will now be emulated. > o The CPU's random register now considers the value of the wired register Great stuff... > Known bugs: > > o ll/sc don't use a ll_bit like the real hardware thus right now any atomic > functions aren't really atomic. I suppose you know that the CPUs all implement "break link on exception" by zeroing the link bit on an 'eret'? That doesn't sound too hard... > o ll/sc really should be watching a physical not a virtual address or they > won't do much useful on any kind of shared memory structure. > o MIPS documentation documents the lladdr register to contain the virtual > address of the location being watched but about every implementation > since the R4000 actually keeps the physical address there - and documents > that as an erratum even though it actually the sensible thing to do. We > should do the same. Fortunately nothing that I know of actually relies > on the content of the lladdr register, so this one is cosmetic. Arguably, an emulator should not provide the LLaddr register at all. It's optional and "only available for debug" - and probably such debugging is possible another way in an emulator. Robust software shouldn't depend on assuming the contents make sense. > ... > Kernel panic - not syncing: No init found. Try passing init= option to kernel. > > Which is a bug - there is a valid root filesystem. Something for tomorrow. Not quite there yet... but well done, again. -- Dominic
