On a data page fault or dtlb miss, the exception handler doesn't know why it failed. Was it protection fault? was it for a read or a write? On a bus error, it's even worse since you have no idea whatsoever what caused.
A symdrome register indicating why the fault happened would be nice (for l.sys, the syscall number could be placed in it). Otherwise the kernel is forced to read the instruction to determine the fault. _______________________________________________ OpenRISC mailing list [email protected] http://lists.openrisc.net/listinfo/openrisc
