arch/sparc/kernel/jump_label.c

   1 #include <linux/kernel.h>
   2 #include <linux/types.h>
   3 #include <linux/mutex.h>
   4 #include <linux/cpu.h>
   5
   6 #include <linux/jump_label.h>
   7 #include <linux/memory.h>
   8
   9 #include <asm/cacheflush.h>
  10
  11 #ifdef HAVE_JUMP_LABEL
  12
  13 void arch_jump_label_transform(struct jump_entry *entry,
  14                                enum jump_label_type type)
  15 {
  16         u32 *insn = (u32 *) (unsigned long) entry->code;
  17         u32 val;
  18
  19         if (type == JUMP_LABEL_JMP) {
  20                 s32 off = (s32)entry->target - (s32)entry->code;
  21                 bool use_v9_branch = false;
  22
  23                 BUG_ON(off & 3);
  24
  25 #ifdef CONFIG_SPARC64
  26                 if (off <= 0xfffff && off >= -0x100000)
  27                         use_v9_branch = true;
  28 #endif
  29                 if (use_v9_branch) {
  30                         /* WDISP19 - target is . + immed << 2 */
  31                         /* ba,pt %xcc, . + off */
  32                         val = 0x10680000 | (((u32) off >> 2) & 0x7ffff);
  33                 } else {
  34                         /* WDISP22 - target is . + immed << 2 */
  35                         BUG_ON(off > 0x7fffff);
  36                         BUG_ON(off < -0x800000);
  37                         /* ba . + off */
  38                         val = 0x10800000 | (((u32) off >> 2) & 0x3fffff);
  39                 }
  40         } else {
  41                 val = 0x01000000;
  42         }
  43
  44         mutex_lock(&text_mutex);
  45         *insn = val;
  46         flushi(insn);
  47         mutex_unlock(&text_mutex);
  48 }
  49
  50 #endif