xenivt.S 1.2 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253
  1. /*
  2. * arch/ia64/xen/ivt.S
  3. *
  4. * Copyright (C) 2005 Hewlett-Packard Co
  5. * Dan Magenheimer <dan.magenheimer@hp.com>
  6. *
  7. * Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp>
  8. * VA Linux Systems Japan K.K.
  9. * pv_ops.
  10. */
  11. #include <asm/asmmacro.h>
  12. #include <asm/kregs.h>
  13. #include <asm/pgtable.h>
  14. #include "../kernel/minstate.h"
  15. .section .text,"ax"
  16. GLOBAL_ENTRY(xen_event_callback)
  17. mov r31=pr // prepare to save predicates
  18. ;;
  19. SAVE_MIN_WITH_COVER // uses r31; defines r2 and r3
  20. ;;
  21. movl r3=XSI_PSR_IC
  22. mov r14=1
  23. ;;
  24. st4 [r3]=r14
  25. ;;
  26. adds r3=8,r2 // set up second base pointer for SAVE_REST
  27. srlz.i // ensure everybody knows psr.ic is back on
  28. ;;
  29. SAVE_REST
  30. ;;
  31. 1:
  32. alloc r14=ar.pfs,0,0,1,0 // must be first in an insn group
  33. add out0=16,sp // pass pointer to pt_regs as first arg
  34. ;;
  35. br.call.sptk.many b0=xen_evtchn_do_upcall
  36. ;;
  37. movl r20=XSI_PSR_I_ADDR
  38. ;;
  39. ld8 r20=[r20]
  40. ;;
  41. adds r20=-1,r20 // vcpu_info->evtchn_upcall_pending
  42. ;;
  43. ld1 r20=[r20]
  44. ;;
  45. cmp.ne p6,p0=r20,r0 // if there are pending events,
  46. (p6) br.spnt.few 1b // call evtchn_do_upcall again.
  47. br.sptk.many xen_leave_kernel // we know ia64_leave_kernel is
  48. // paravirtualized as xen_leave_kernel
  49. END(xen_event_callback)