arch/sparc64/kernel/ktlb.S

   1 /* arch/sparc64/kernel/ktlb.S: Kernel mapping TLB miss handling.
   2  *
   3  * Copyright (C) 1995, 1997, 2005 David S. Miller <davem@davemloft.net>
   4  * Copyright (C) 1996 Eddie C. Dost        (ecd@brainaid.de)
   5  * Copyright (C) 1996 Miguel de Icaza      (miguel@nuclecu.unam.mx)
   6  * Copyright (C) 1996,98,99 Jakub Jelinek  (jj@sunsite.mff.cuni.cz)
   7  */
   8
   9 #include <linux/config.h>
  10 #include <asm/head.h>
  11 #include <asm/asi.h>
  12 #include <asm/page.h>
  13 #include <asm/pgtable.h>
  14 #include <asm/tsb.h>
  15
  16         .text
  17         .align          32
  18
  19         .globl          kvmap_itlb
  20 kvmap_itlb:
  21         /* g6: TAG TARGET */
  22         mov             TLB_TAG_ACCESS, %g4
  23         ldxa            [%g4] ASI_IMMU, %g4
  24
  25 kvmap_itlb_nonlinear:
  26         /* Catch kernel NULL pointer calls.  */
  27         sethi           %hi(PAGE_SIZE), %g5
  28         cmp             %g4, %g5
  29         bleu,pn         %xcc, kvmap_dtlb_longpath
  30          nop
  31
  32         KERN_TSB_LOOKUP_TL1(%g4, %g6, %g5, %g1, %g2, %g3, kvmap_itlb_load)
  33
  34 kvmap_itlb_tsb_miss:
  35         sethi           %hi(LOW_OBP_ADDRESS), %g5
  36         cmp             %g4, %g5
  37         blu,pn          %xcc, kvmap_itlb_vmalloc_addr
  38          mov            0x1, %g5
  39         sllx            %g5, 32, %g5
  40         cmp             %g4, %g5
  41         blu,pn          %xcc, kvmap_itlb_obp
  42          nop
  43
  44 kvmap_itlb_vmalloc_addr:
  45         KERN_PGTABLE_WALK(%g4, %g5, %g2, kvmap_itlb_longpath)
  46
  47         TSB_LOCK_TAG(%g1, %g2, %g4)
  48
  49         /* Load and check PTE.  */
  50         ldxa            [%g5] ASI_PHYS_USE_EC, %g5
  51         brgez,a,pn      %g5, kvmap_itlb_longpath
  52          stx            %g0, [%g1]
  53
  54         TSB_WRITE(%g1, %g5, %g6)
  55
  56         /* fallthrough to TLB load */
  57
  58 kvmap_itlb_load:
  59         stxa            %g5, [%g0] ASI_ITLB_DATA_IN     ! Reload TLB
  60         retry
  61
  62 kvmap_itlb_longpath:
  63         rdpr    %pstate, %g5
  64         wrpr    %g5, PSTATE_AG | PSTATE_MG, %pstate
  65         rdpr    %tpc, %g5
  66         ba,pt   %xcc, sparc64_realfault_common
  67          mov    FAULT_CODE_ITLB, %g4
  68
  69 kvmap_itlb_obp:
  70         OBP_TRANS_LOOKUP(%g4, %g5, %g2, %g3, kvmap_itlb_longpath)
  71
  72         TSB_LOCK_TAG(%g1, %g2, %g4)
  73
  74         TSB_WRITE(%g1, %g5, %g6)
  75
  76         ba,pt           %xcc, kvmap_itlb_load
  77          nop
  78
  79 kvmap_dtlb_obp:
  80         OBP_TRANS_LOOKUP(%g4, %g5, %g2, %g3, kvmap_dtlb_longpath)
  81
  82         TSB_LOCK_TAG(%g1, %g2, %g4)
  83
  84         TSB_WRITE(%g1, %g5, %g6)
  85
  86         ba,pt           %xcc, kvmap_dtlb_load
  87          nop
  88
  89         .align          32
  90         .globl          kvmap_dtlb
  91 kvmap_dtlb:
  92         /* %g6: TAG TARGET */
  93         mov             TLB_TAG_ACCESS, %g4
  94         ldxa            [%g4] ASI_DMMU, %g4
  95         brgez,pn        %g4, kvmap_dtlb_nonlinear
  96          nop
  97
  98 #define KERN_HIGHBITS   ((_PAGE_VALID|_PAGE_SZ4MB)^0xfffff80000000000)
  99 #define KERN_LOWBITS    (_PAGE_CP | _PAGE_CV | _PAGE_P | _PAGE_W)
 100
 101         sethi           %uhi(KERN_HIGHBITS), %g2
 102         or              %g2, %ulo(KERN_HIGHBITS), %g2
 103         sllx            %g2, 32, %g2
 104         or              %g2, KERN_LOWBITS, %g2
 105
 106 #undef KERN_HIGHBITS
 107 #undef KERN_LOWBITS
 108
 109         .globl          kvmap_linear_patch
 110 kvmap_linear_patch:
 111         ba,pt           %xcc, kvmap_dtlb_load
 112          xor            %g2, %g4, %g5
 113
 114 kvmap_dtlb_vmalloc_addr:
 115         KERN_PGTABLE_WALK(%g4, %g5, %g2, kvmap_dtlb_longpath)
 116
 117         TSB_LOCK_TAG(%g1, %g2, %g4)
 118
 119         /* Load and check PTE.  */
 120         ldxa            [%g5] ASI_PHYS_USE_EC, %g5
 121         brgez,a,pn      %g5, kvmap_dtlb_longpath
 122          stx            %g0, [%g1]
 123
 124         TSB_WRITE(%g1, %g5, %g6)
 125
 126         /* fallthrough to TLB load */
 127
 128 kvmap_dtlb_load:
 129         stxa            %g5, [%g0] ASI_DTLB_DATA_IN     ! Reload TLB
 130         retry
 131
 132 kvmap_dtlb_nonlinear:
 133         /* Catch kernel NULL pointer derefs.  */
 134         sethi           %hi(PAGE_SIZE), %g5
 135         cmp             %g4, %g5
 136         bleu,pn         %xcc, kvmap_dtlb_longpath
 137          nop
 138
 139         KERN_TSB_LOOKUP_TL1(%g4, %g6, %g5, %g1, %g2, %g3, kvmap_dtlb_load)
 140
 141 kvmap_dtlb_tsbmiss:
 142         sethi           %hi(MODULES_VADDR), %g5
 143         cmp             %g4, %g5
 144         blu,pn          %xcc, kvmap_dtlb_longpath
 145          mov            (VMALLOC_END >> 24), %g5
 146         sllx            %g5, 24, %g5
 147         cmp             %g4, %g5
 148         bgeu,pn         %xcc, kvmap_dtlb_longpath
 149          nop
 150
 151 kvmap_check_obp:
 152         sethi           %hi(LOW_OBP_ADDRESS), %g5
 153         cmp             %g4, %g5
 154         blu,pn          %xcc, kvmap_dtlb_vmalloc_addr
 155          mov            0x1, %g5
 156         sllx            %g5, 32, %g5
 157         cmp             %g4, %g5
 158         blu,pn          %xcc, kvmap_dtlb_obp
 159          nop
 160         ba,pt           %xcc, kvmap_dtlb_vmalloc_addr
 161          nop
 162
 163 kvmap_dtlb_longpath:
 164         rdpr    %pstate, %g5
 165         wrpr    %g5, PSTATE_AG | PSTATE_MG, %pstate
 166         rdpr    %tl, %g4
 167         cmp     %g4, 1
 168         mov     TLB_TAG_ACCESS, %g4
 169         ldxa    [%g4] ASI_DMMU, %g5
 170         be,pt   %xcc, sparc64_realfault_common
 171          mov    FAULT_CODE_DTLB, %g4
 172         ba,pt   %xcc, winfix_trampoline
 173          nop