| 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
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| 2 | /* |
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| 3 | * dtlb_prot.S: DTLB protection trap strategy. |
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| 4 | * This is included directly into the trap table. |
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| 5 | * |
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| 6 | * Copyright (C) 1996,1998 David S. Miller (davem@redhat.com) |
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| 7 | * Copyright (C) 1997,1998 Jakub Jelinek (jj@ultra.linux.cz) |
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| 8 | */ |
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| 9 | |
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| 10 | /* Ways we can get here: |
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| 11 | * |
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| 12 | * [TL == 0] 1) User stores to readonly pages. |
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| 13 | * [TL == 0] 2) Nucleus stores to user readonly pages. |
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| 14 | * [TL > 0] 3) Nucleus stores to user readonly stack frame. |
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| 15 | */ |
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| 16 | |
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| 17 | /* PROT ** ICACHE line 1: User DTLB protection trap */ |
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| 18 | mov TLB_SFSR, %g1 |
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| 19 | stxa %g0, [%g1] ASI_DMMU ! Clear FaultValid bit |
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| 20 | membar #Sync ! Synchronize stores |
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| 21 | rdpr %pstate, %g5 ! Move into alt-globals |
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| 22 | wrpr %g5, PSTATE_AG|PSTATE_MG, %pstate |
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| 23 | rdpr %tl, %g1 ! Need a winfixup? |
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| 24 | cmp %g1, 1 ! Trap level >1? |
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| 25 | mov TLB_TAG_ACCESS, %g4 ! For reload of vaddr |
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| 26 | |
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| 27 | /* PROT ** ICACHE line 2: More real fault processing */ |
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| 28 | ldxa [%g4] ASI_DMMU, %g5 ! Put tagaccess in %g5 |
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| 29 | srlx %g5, PAGE_SHIFT, %g5 |
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| 30 | sllx %g5, PAGE_SHIFT, %g5 ! Clear context ID bits |
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| 31 | bgu,pn %xcc, winfix_trampoline ! Yes, perform winfixup |
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| 32 | mov FAULT_CODE_DTLB | FAULT_CODE_WRITE, %g4 |
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| 33 | ba,pt %xcc, sparc64_realfault_common ! Nope, normal fault |
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| 34 | nop |
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| 35 | nop |
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| 36 | |
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| 37 | /* PROT ** ICACHE line 3: Unused... */ |
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| 38 | nop |
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| 39 | nop |
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| 40 | nop |
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| 41 | nop |
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| 42 | nop |
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| 43 | nop |
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| 44 | nop |
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| 45 | nop |
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| 46 | |
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| 47 | /* PROT ** ICACHE line 4: Unused... */ |
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| 48 | nop |
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| 49 | nop |
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| 50 | nop |
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| 51 | nop |
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| 52 | nop |
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| 53 | nop |
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| 54 | nop |
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| 55 | nop |
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| 56 | |
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