root/arch/sparc/lib/GENpatch.S

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /* GENpatch.S: Patch Ultra-I routines with generic variant.
   3  *
   4  * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
   5  */
   6 
   7 #define BRANCH_ALWAYS   0x10680000
   8 #define NOP             0x01000000
   9 #define GEN_DO_PATCH(OLD, NEW)  \
  10         sethi   %hi(NEW), %g1; \
  11         or      %g1, %lo(NEW), %g1; \
  12         sethi   %hi(OLD), %g2; \
  13         or      %g2, %lo(OLD), %g2; \
  14         sub     %g1, %g2, %g1; \
  15         sethi   %hi(BRANCH_ALWAYS), %g3; \
  16         sll     %g1, 11, %g1; \
  17         srl     %g1, 11 + 2, %g1; \
  18         or      %g3, %lo(BRANCH_ALWAYS), %g3; \
  19         or      %g3, %g1, %g3; \
  20         stw     %g3, [%g2]; \
  21         sethi   %hi(NOP), %g3; \
  22         or      %g3, %lo(NOP), %g3; \
  23         stw     %g3, [%g2 + 0x4]; \
  24         flush   %g2;
  25 
  26         .globl  generic_patch_copyops
  27         .type   generic_patch_copyops,#function
  28 generic_patch_copyops:
  29         GEN_DO_PATCH(memcpy, GENmemcpy)
  30         GEN_DO_PATCH(raw_copy_from_user, GENcopy_from_user)
  31         GEN_DO_PATCH(raw_copy_to_user, GENcopy_to_user)
  32         retl
  33          nop
  34         .size   generic_patch_copyops,.-generic_patch_copyops