// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2020 Emil Renner Berthing
 *
 * Based on arch/arm64/kernel/jump_label.c
 */
#include <linux/jump_label.h>
#include <linux/kernel.h>
#include <linux/memory.h>
#include <linux/mutex.h>
#include <asm/bug.h>
#include <asm/cacheflush.h>
#include <asm/text-patching.h>
#include <asm/insn-def.h>

#define RISCV_INSN_JAL 0x0000006fU

bool arch_jump_label_transform_queue(struct jump_entry *entry,
                                     enum jump_label_type type)
{
        void *addr = (void *)jump_entry_code(entry);
        u32 insn;

        if (type == JUMP_LABEL_JMP) {
                long offset = jump_entry_target(entry) - jump_entry_code(entry);

                if (WARN_ON(offset & 1 || offset < -524288 || offset >= 524288))
                        return true;

                insn = RISCV_INSN_JAL |
                        (((u32)offset & GENMASK(19, 12)) << (12 - 12)) |
                        (((u32)offset & GENMASK(11, 11)) << (20 - 11)) |
                        (((u32)offset & GENMASK(10,  1)) << (21 -  1)) |
                        (((u32)offset & GENMASK(20, 20)) << (31 - 20));
        } else {
                insn = RISCV_INSN_NOP4;
        }

        if (early_boot_irqs_disabled) {
                riscv_patch_in_stop_machine = 1;
                patch_insn_write(addr, &insn, sizeof(insn));
                riscv_patch_in_stop_machine = 0;
        } else {
                mutex_lock(&text_mutex);
                patch_insn_write(addr, &insn, sizeof(insn));
                mutex_unlock(&text_mutex);
        }

        return true;
}

void arch_jump_label_transform_apply(void)
{
        flush_icache_all();
}