arch/arm64/lib/call_with_stack.S

   1 /*
   2  * arch/arm64/lib/call_with_stack.S
   3  *
   4  */
   5
   6 #include <linux/linkage.h>
   7 #include <asm/assembler.h>
   8
   9 /*
  10  * void call_with_stack(void (*fn)(void *), void *arg, void *sp)
  11  *
  12  * Change the stack to that pointed at by sp, then invoke fn(arg) with
  13  * the new stack.
  14  */
  15 ENTRY(call_with_stack)
  16         mov     x3, sp
  17         str     x3, [x2, #-8]!
  18         str     lr, [x2, #-8]!
  19
  20         mov     sp, x2
  21         mov     x2, x0
  22         mov     x0, x1
  23
  24         adr     lr, 1f
  25         br      x2
  26
  27 1:      ldr     lr, [sp]
  28         ldr     x3, [sp, #8]
  29         mov     sp, x3
  30         br      lr
  31 ENDPROC(call_with_stack)