arch/arm/include/asm/setjmp.h

   1 /*
   2  * (C) Copyright 2016
   3  * Alexander Graf <agraf@suse.de>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #ifndef _SETJMP_H_
   9 #define _SETJMP_H_      1
  10
  11 struct jmp_buf_data {
  12         ulong target;
  13         ulong regs[5];
  14         int ret;
  15 };
  16
  17 typedef struct jmp_buf_data jmp_buf[1];
  18
  19 static inline int setjmp(jmp_buf jmp)
  20 {
  21         jmp->ret = 0;
  22
  23 #ifdef CONFIG_ARM64
  24         asm volatile(
  25                 "adr x1, jmp_target\n"
  26                 "str x1, %0\n"
  27                 "stp x26, x27, %1\n"
  28                 "stp x28, x29, %2\n"
  29                 "mov x1, sp\n"
  30                 "str x1, %3\n"
  31                 "jmp_target: "
  32                 : "=m" (jmp->target), "=m" (jmp->regs[0]),
  33                   "=m" (jmp->regs[2]), "=m" (jmp->regs[4])
  34                 :
  35                 : "x0", "x1", "x2", "x3", "x4", "x5", "x6", "x7",
  36                   "x8", "x9", "x10", "x11", "x12", "x13", "x14", "x15",
  37                   "x16", "x17", "x18", "x19", "x20", "x21", "x22",
  38                   "x23", "x24", "x25", /* x26, x27, x28, x29, sp */
  39                   "x30", "cc", "memory");
  40 #else
  41         asm volatile(
  42 #if CONFIG_IS_ENABLED(SYS_THUMB_BUILD)
  43                 ".align 2\n"
  44                 "adr r0, jmp_target\n"
  45                 "add r0, r0, $1\n"
  46 #else
  47                 "adr r0, jmp_target\n"
  48 #endif
  49                 "mov r1, %0\n"
  50                 "mov r2, sp\n"
  51                 "stm r1!, {r0, r2, r4, r5, r6, r7}\n"
  52                 ".align 2\n"
  53                 "jmp_target: \n"
  54                 :
  55                 : "l" (&jmp->target)
  56                 : "r0", "r1", "r2", "r3", /* "r4", "r5", "r6", "r7", */
  57                   "r8", "r9", "r10", "r11", /* sp, */ "ip", "lr",
  58                   "cc", "memory");
  59 #endif
  60
  61         return jmp->ret;
  62 }
  63
  64 static inline __noreturn void longjmp(jmp_buf jmp, int ret)
  65 {
  66         jmp->ret = ret;
  67
  68 #ifdef CONFIG_ARM64
  69         asm volatile(
  70                 "ldr x0, %0\n"
  71                 "ldr x1, %3\n"
  72                 "mov sp, x1\n"
  73                 "ldp x26, x27, %1\n"
  74                 "ldp x28, x25, %2\n"
  75                 "mov x29, x25\n"
  76                 "br x0\n"
  77                 :
  78                 : "m" (jmp->target), "m" (jmp->regs[0]), "m" (jmp->regs[2]),
  79                   "m" (jmp->regs[4])
  80                 : "x0", "x1", "x25", "x26", "x27", "x28");
  81 #else
  82         asm volatile(
  83                 "mov r1, %0\n"
  84                 "ldm r1!, {r0, r2, r4, r5, r6, r7}\n"
  85                 "mov sp, r2\n"
  86                 "bx r0\n"
  87                 :
  88                 : "l" (&jmp->target)
  89                 : "r1");
  90 #endif
  91
  92         while (1) { }
  93 }
  94
  95
  96 #endif /* _SETJMP_H_ */