minstate.h 5.5 KB

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  1. #ifdef CONFIG_VIRT_CPU_ACCOUNTING
  2. /* read ar.itc in advance, and use it before leaving bank 0 */
  3. #define XEN_ACCOUNT_GET_STAMP \
  4. MOV_FROM_ITC(pUStk, p6, r20, r2);
  5. #else
  6. #define XEN_ACCOUNT_GET_STAMP
  7. #endif
  8. /*
  9. * DO_SAVE_MIN switches to the kernel stacks (if necessary) and saves
  10. * the minimum state necessary that allows us to turn psr.ic back
  11. * on.
  12. *
  13. * Assumed state upon entry:
  14. * psr.ic: off
  15. * r31: contains saved predicates (pr)
  16. *
  17. * Upon exit, the state is as follows:
  18. * psr.ic: off
  19. * r2 = points to &pt_regs.r16
  20. * r8 = contents of ar.ccv
  21. * r9 = contents of ar.csd
  22. * r10 = contents of ar.ssd
  23. * r11 = FPSR_DEFAULT
  24. * r12 = kernel sp (kernel virtual address)
  25. * r13 = points to current task_struct (kernel virtual address)
  26. * p15 = TRUE if psr.i is set in cr.ipsr
  27. * predicate registers (other than p2, p3, and p15), b6, r3, r14, r15:
  28. * preserved
  29. * CONFIG_XEN note: p6/p7 are not preserved
  30. *
  31. * Note that psr.ic is NOT turned on by this macro. This is so that
  32. * we can pass interruption state as arguments to a handler.
  33. */
  34. #define XEN_DO_SAVE_MIN(__COVER,SAVE_IFS,EXTRA,WORKAROUND) \
  35. mov r16=IA64_KR(CURRENT); /* M */ \
  36. mov r27=ar.rsc; /* M */ \
  37. mov r20=r1; /* A */ \
  38. mov r25=ar.unat; /* M */ \
  39. MOV_FROM_IPSR(p0,r29); /* M */ \
  40. MOV_FROM_IIP(r28); /* M */ \
  41. mov r21=ar.fpsr; /* M */ \
  42. mov r26=ar.pfs; /* I */ \
  43. __COVER; /* B;; (or nothing) */ \
  44. adds r16=IA64_TASK_THREAD_ON_USTACK_OFFSET,r16; \
  45. ;; \
  46. ld1 r17=[r16]; /* load current->thread.on_ustack flag */ \
  47. st1 [r16]=r0; /* clear current->thread.on_ustack flag */ \
  48. adds r1=-IA64_TASK_THREAD_ON_USTACK_OFFSET,r16 \
  49. /* switch from user to kernel RBS: */ \
  50. ;; \
  51. invala; /* M */ \
  52. /* SAVE_IFS;*/ /* see xen special handling below */ \
  53. cmp.eq pKStk,pUStk=r0,r17; /* are we in kernel mode already? */ \
  54. ;; \
  55. (pUStk) mov ar.rsc=0; /* set enforced lazy mode, pl 0, little-endian, loadrs=0 */ \
  56. ;; \
  57. (pUStk) mov.m r24=ar.rnat; \
  58. (pUStk) addl r22=IA64_RBS_OFFSET,r1; /* compute base of RBS */ \
  59. (pKStk) mov r1=sp; /* get sp */ \
  60. ;; \
  61. (pUStk) lfetch.fault.excl.nt1 [r22]; \
  62. (pUStk) addl r1=IA64_STK_OFFSET-IA64_PT_REGS_SIZE,r1; /* compute base of memory stack */ \
  63. (pUStk) mov r23=ar.bspstore; /* save ar.bspstore */ \
  64. ;; \
  65. (pUStk) mov ar.bspstore=r22; /* switch to kernel RBS */ \
  66. (pKStk) addl r1=-IA64_PT_REGS_SIZE,r1; /* if in kernel mode, use sp (r12) */ \
  67. ;; \
  68. (pUStk) mov r18=ar.bsp; \
  69. (pUStk) mov ar.rsc=0x3; /* set eager mode, pl 0, little-endian, loadrs=0 */ \
  70. adds r17=2*L1_CACHE_BYTES,r1; /* really: biggest cache-line size */ \
  71. adds r16=PT(CR_IPSR),r1; \
  72. ;; \
  73. lfetch.fault.excl.nt1 [r17],L1_CACHE_BYTES; \
  74. st8 [r16]=r29; /* save cr.ipsr */ \
  75. ;; \
  76. lfetch.fault.excl.nt1 [r17]; \
  77. tbit.nz p15,p0=r29,IA64_PSR_I_BIT; \
  78. mov r29=b0 \
  79. ;; \
  80. WORKAROUND; \
  81. adds r16=PT(R8),r1; /* initialize first base pointer */ \
  82. adds r17=PT(R9),r1; /* initialize second base pointer */ \
  83. (pKStk) mov r18=r0; /* make sure r18 isn't NaT */ \
  84. ;; \
  85. .mem.offset 0,0; st8.spill [r16]=r8,16; \
  86. .mem.offset 8,0; st8.spill [r17]=r9,16; \
  87. ;; \
  88. .mem.offset 0,0; st8.spill [r16]=r10,24; \
  89. movl r8=XSI_PRECOVER_IFS; \
  90. .mem.offset 8,0; st8.spill [r17]=r11,24; \
  91. ;; \
  92. /* xen special handling for possibly lazy cover */ \
  93. /* SAVE_MIN case in dispatch_ia32_handler: mov r30=r0 */ \
  94. ld8 r30=[r8]; \
  95. (pUStk) sub r18=r18,r22; /* r18=RSE.ndirty*8 */ \
  96. st8 [r16]=r28,16; /* save cr.iip */ \
  97. ;; \
  98. st8 [r17]=r30,16; /* save cr.ifs */ \
  99. mov r8=ar.ccv; \
  100. mov r9=ar.csd; \
  101. mov r10=ar.ssd; \
  102. movl r11=FPSR_DEFAULT; /* L-unit */ \
  103. ;; \
  104. st8 [r16]=r25,16; /* save ar.unat */ \
  105. st8 [r17]=r26,16; /* save ar.pfs */ \
  106. shl r18=r18,16; /* compute ar.rsc to be used for "loadrs" */ \
  107. ;; \
  108. st8 [r16]=r27,16; /* save ar.rsc */ \
  109. (pUStk) st8 [r17]=r24,16; /* save ar.rnat */ \
  110. (pKStk) adds r17=16,r17; /* skip over ar_rnat field */ \
  111. ;; /* avoid RAW on r16 & r17 */ \
  112. (pUStk) st8 [r16]=r23,16; /* save ar.bspstore */ \
  113. st8 [r17]=r31,16; /* save predicates */ \
  114. (pKStk) adds r16=16,r16; /* skip over ar_bspstore field */ \
  115. ;; \
  116. st8 [r16]=r29,16; /* save b0 */ \
  117. st8 [r17]=r18,16; /* save ar.rsc value for "loadrs" */ \
  118. cmp.eq pNonSys,pSys=r0,r0 /* initialize pSys=0, pNonSys=1 */ \
  119. ;; \
  120. .mem.offset 0,0; st8.spill [r16]=r20,16; /* save original r1 */ \
  121. .mem.offset 8,0; st8.spill [r17]=r12,16; \
  122. adds r12=-16,r1; /* switch to kernel memory stack (with 16 bytes of scratch) */ \
  123. ;; \
  124. .mem.offset 0,0; st8.spill [r16]=r13,16; \
  125. .mem.offset 8,0; st8.spill [r17]=r21,16; /* save ar.fpsr */ \
  126. mov r13=IA64_KR(CURRENT); /* establish `current' */ \
  127. ;; \
  128. .mem.offset 0,0; st8.spill [r16]=r15,16; \
  129. .mem.offset 8,0; st8.spill [r17]=r14,16; \
  130. ;; \
  131. .mem.offset 0,0; st8.spill [r16]=r2,16; \
  132. .mem.offset 8,0; st8.spill [r17]=r3,16; \
  133. XEN_ACCOUNT_GET_STAMP \
  134. adds r2=IA64_PT_REGS_R16_OFFSET,r1; \
  135. ;; \
  136. EXTRA; \
  137. movl r1=__gp; /* establish kernel global pointer */ \
  138. ;; \
  139. ACCOUNT_SYS_ENTER \
  140. BSW_1(r3,r14); /* switch back to bank 1 (must be last in insn group) */ \
  141. ;;