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review.evervolv.com / android_kernel_htc_msm8960 / c541c15fb5ab48c47bc9b90121538fd30d152f23 / . / arch / sparc / kernel / dtlb_prot.S
blob: b2c2c5be281c436f25b8cb66353546d9fcd8f82c [file] [log] [blame]
Adrian Bunkb00dc832008-05-19 16:52:27 -0700[diff] [blame]1/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]2 * dtlb_prot.S: DTLB protection trap strategy.
3 * This is included directly into the trap table.
4 *
5 * Copyright (C) 1996,1998 David S. Miller (davem@redhat.com)
6 * Copyright (C) 1997,1998 Jakub Jelinek (jj@ultra.linux.cz)
7 */
8
9/* Ways we can get here:
10 *
11 * [TL == 0] 1) User stores to readonly pages.
12 * [TL == 0] 2) Nucleus stores to user readonly pages.
13 * [TL > 0] 3) Nucleus stores to user readonly stack frame.
14 */
15
16/* PROT ** ICACHE line 1: User DTLB protection trap */
David S. Millerc9c10832005-10-12 12:22:46 -0700[diff] [blame]17 mov TLB_SFSR, %g1
18 stxa %g0, [%g1] ASI_DMMU ! Clear FaultValid bit
19 membar #Sync ! Synchronize stores
20 rdpr %pstate, %g5 ! Move into alt-globals
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]21 wrpr %g5, PSTATE_AG|PSTATE_MG, %pstate
David S. Millerc9c10832005-10-12 12:22:46 -0700[diff] [blame]22 rdpr %tl, %g1 ! Need a winfixup?
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]23 cmp %g1, 1 ! Trap level >1?
David S. Millerc9c10832005-10-12 12:22:46 -0700[diff] [blame]24 mov TLB_TAG_ACCESS, %g4 ! For reload of vaddr
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]25
26/* PROT ** ICACHE line 2: More real fault processing */
27 bgu,pn %xcc, winfix_trampoline ! Yes, perform winfixup
28 ldxa [%g4] ASI_DMMU, %g5 ! Put tagaccess in %g5
29 ba,pt %xcc, sparc64_realfault_common ! Nope, normal fault
30 mov FAULT_CODE_DTLB | FAULT_CODE_WRITE, %g4
31 nop
32 nop
33 nop
34 nop
35
36/* PROT ** ICACHE line 3: Unused... */
37 nop
38 nop
39 nop
40 nop
41 nop
42 nop
43 nop
44 nop
45
46/* PROT ** ICACHE line 4: Unused... */
47 nop
48 nop
49 nop
50 nop
51 nop
52 nop
53 nop
54 nop