root/arch/arm/include/asm/insn.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_ARM_INSN_H
#define __ASM_ARM_INSN_H

#include <linux/types.h>

/*
 * Avoid a literal load by emitting a sequence of ADD/LDR instructions with the
 * appropriate relocations. The combined sequence has a range of -/+ 256 MiB,
 * which should be sufficient for the core kernel as well as modules loaded
 * into the module region. (Not supported by LLD before release 14)
 */
#define LOAD_SYM_ARMV6(reg, sym)                                        \
        "       .globl  " #sym "                                \n\t"   \
        "       .reloc  10f, R_ARM_ALU_PC_G0_NC, " #sym "       \n\t"   \
        "       .reloc  11f, R_ARM_ALU_PC_G1_NC, " #sym "       \n\t"   \
        "       .reloc  12f, R_ARM_LDR_PC_G2, " #sym "          \n\t"   \
        "10:    sub     " #reg ", pc, #8                        \n\t"   \
        "11:    sub     " #reg ", " #reg ", #4                  \n\t"   \
        "12:    ldr     " #reg ", [" #reg ", #0]                \n\t"

static inline unsigned long
arm_gen_nop(void)
{
#ifdef CONFIG_THUMB2_KERNEL
        return 0xf3af8000; /* nop.w */
#else
        return 0xe1a00000; /* mov r0, r0 */
#endif
}

unsigned long
__arm_gen_branch(unsigned long pc, unsigned long addr, bool link, bool warn);

static inline unsigned long
arm_gen_branch(unsigned long pc, unsigned long addr)
{
        return __arm_gen_branch(pc, addr, false, true);
}

static inline unsigned long
arm_gen_branch_link(unsigned long pc, unsigned long addr, bool warn)
{
        return __arm_gen_branch(pc, addr, true, warn);
}

#endif