Tlb parity error recovery

Abstract

A microprocessor, data processing system, and method are disclosed for handling parity errors in an address translation facility such as a TLB. The microprocessor includes a load/store unit configured to generate an effective address associated with a load/store instruction. An address translation unit adapted to translate the effective address to a real address using a translation lookaside buffer (TLB). The address translation unit includes a parity checker configured to verify the parity of the real address generated by the TLB and to signal the load store unit when the real address contains a parity error. The load store unit is configured to initiate a TLB parity error interrupt routine in response to the signal from the translation unit. In one embodiment, the TLB interrupt routine selectively invalidates the TLB entry that contained the parity error. The load/store unit preferably includes an effective to real address table (ERAT) containing a set of address translations. In this embodiment, the load/store unit invokes the address translation unit to translate the effective address only if the effective address misses in the ERAT. The LSU may suitably include an ERAT miss queue (EMQ) adapted to retain an effective address that misses in the ERAT until the address translation unit completes the translation process. In this embodiment, the EMQ is configured to issue a TLB parity error interrupt signal to initiate the TLB parity error interrupt routine. In one embodiment, the TLB interrupt routine loads a data address register (DAR) of the microprocessor with the effective address of the instruction that resulted in the parity error. The TLB interrupt routine may further set a data storage interrupt routine status register (DSISR) to indicate the TLB parity error.