xref: /openbmc/linux/arch/arm/include/asm/insn.h (revision 7b9896c352073156a325c3bb0dc4c46e06e2a468)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_ARM_INSN_H
3 #define __ASM_ARM_INSN_H
4 
5 #include <linux/types.h>
6 
7 /*
8  * Avoid a literal load by emitting a sequence of ADD/LDR instructions with the
9  * appropriate relocations. The combined sequence has a range of -/+ 256 MiB,
10  * which should be sufficient for the core kernel as well as modules loaded
11  * into the module region. (Not supported by LLD before release 14)
12  */
13 #if !(defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS)) && \
14     !(defined(CONFIG_LD_IS_LLD) && CONFIG_LLD_VERSION < 140000)
15 #define LOAD_SYM_ARMV6(reg, sym)					\
16 	"	.globl	" #sym "				\n\t"	\
17 	"	.reloc	10f, R_ARM_ALU_PC_G0_NC, " #sym "	\n\t"	\
18 	"	.reloc	11f, R_ARM_ALU_PC_G1_NC, " #sym "	\n\t"	\
19 	"	.reloc	12f, R_ARM_LDR_PC_G2, " #sym "		\n\t"	\
20 	"10:	sub	" #reg ", pc, #8			\n\t"	\
21 	"11:	sub	" #reg ", " #reg ", #4			\n\t"	\
22 	"12:	ldr	" #reg ", [" #reg ", #0]		\n\t"
23 #else
24 #define LOAD_SYM_ARMV6(reg, sym)					\
25 	"	ldr	" #reg ", =" #sym "			\n\t"	\
26 	"	ldr	" #reg ", [" #reg "]			\n\t"
27 #endif
28 
29 static inline unsigned long
30 arm_gen_nop(void)
31 {
32 #ifdef CONFIG_THUMB2_KERNEL
33 	return 0xf3af8000; /* nop.w */
34 #else
35 	return 0xe1a00000; /* mov r0, r0 */
36 #endif
37 }
38 
39 unsigned long
40 __arm_gen_branch(unsigned long pc, unsigned long addr, bool link, bool warn);
41 
42 static inline unsigned long
43 arm_gen_branch(unsigned long pc, unsigned long addr)
44 {
45 	return __arm_gen_branch(pc, addr, false, true);
46 }
47 
48 static inline unsigned long
49 arm_gen_branch_link(unsigned long pc, unsigned long addr, bool warn)
50 {
51 	return __arm_gen_branch(pc, addr, true, warn);
52 }
53 
54 #endif
55