xref: /openbmc/linux/arch/sparc/kernel/jump_label.c (revision f3a8b664)
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 	get_online_cpus();
45 	mutex_lock(&text_mutex);
46 	*insn = val;
47 	flushi(insn);
48 	mutex_unlock(&text_mutex);
49 	put_online_cpus();
50 }
51 
52 #endif
53