| /* $Id: dtlb_prot.S,v 1.22 2001/04/11 23:40:32 davem Exp $ |
| * dtlb_prot.S: DTLB protection trap strategy. |
| * This is included directly into the trap table. |
| * |
| * Copyright (C) 1996,1998 David S. Miller (davem@redhat.com) |
| * Copyright (C) 1997,1998 Jakub Jelinek (jj@ultra.linux.cz) |
| */ |
| |
| /* Ways we can get here: |
| * |
| * [TL == 0] 1) User stores to readonly pages. |
| * [TL == 0] 2) Nucleus stores to user readonly pages. |
| * [TL > 0] 3) Nucleus stores to user readonly stack frame. |
| */ |
| |
| /* PROT ** ICACHE line 1: User DTLB protection trap */ |
| mov TLB_SFSR, %g1 |
| stxa %g0, [%g1] ASI_DMMU ! Clear FaultValid bit |
| membar #Sync ! Synchronize stores |
| rdpr %pstate, %g5 ! Move into alt-globals |
| wrpr %g5, PSTATE_AG|PSTATE_MG, %pstate |
| rdpr %tl, %g1 ! Need a winfixup? |
| cmp %g1, 1 ! Trap level >1? |
| mov TLB_TAG_ACCESS, %g4 ! For reload of vaddr |
| |
| /* PROT ** ICACHE line 2: More real fault processing */ |
| bgu,pn %xcc, winfix_trampoline ! Yes, perform winfixup |
| ldxa [%g4] ASI_DMMU, %g5 ! Put tagaccess in %g5 |
| ba,pt %xcc, sparc64_realfault_common ! Nope, normal fault |
| mov FAULT_CODE_DTLB | FAULT_CODE_WRITE, %g4 |
| nop |
| nop |
| nop |
| nop |
| |
| /* PROT ** ICACHE line 3: Unused... */ |
| nop |
| nop |
| nop |
| nop |
| nop |
| nop |
| nop |
| nop |
| |
| /* PROT ** ICACHE line 4: Unused... */ |
| nop |
| nop |
| nop |
| nop |
| nop |
| nop |
| nop |
| nop |