root/arch/riscv/include/asm/assembler.h
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2023 StarFive Technology Co., Ltd.
 *
 * Author: Jee Heng Sia <jeeheng.sia@starfivetech.com>
 */

#ifndef __ASSEMBLER__
#error "Only include this from assembly code"
#endif

#ifndef __ASM_ASSEMBLER_H
#define __ASM_ASSEMBLER_H

#include <asm/asm.h>
#include <asm/asm-offsets.h>
#include <asm/csr.h>

/*
 * suspend_restore_csrs - restore CSRs
 */
        .macro suspend_restore_csrs
                REG_L   t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
                csrw    CSR_EPC, t0
                REG_L   t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
                csrw    CSR_STATUS, t0
                REG_L   t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
                csrw    CSR_TVAL, t0
                REG_L   t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)
                csrw    CSR_CAUSE, t0
        .endm

/*
 * suspend_restore_regs - Restore registers (except A0 and T0-T6)
 */
        .macro suspend_restore_regs
                REG_L   ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
                REG_L   sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
                REG_L   gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
                REG_L   tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
                REG_L   s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
                REG_L   s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
                REG_L   a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
                REG_L   a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
                REG_L   a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
                REG_L   a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
                REG_L   a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
                REG_L   a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
                REG_L   a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
                REG_L   s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
                REG_L   s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
                REG_L   s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
                REG_L   s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
                REG_L   s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
                REG_L   s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
                REG_L   s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
                REG_L   s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
                REG_L   s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
                REG_L   s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)
        .endm

/*
 * copy_page - copy 1 page (4KB) of data from source to destination
 * @a0 - destination
 * @a1 - source
 */
        .macro  copy_page a0, a1
                lui     a2, 0x1
                add     a2, a2, a0
1 :
                REG_L   t0, 0(a1)
                REG_L   t1, SZREG(a1)

                REG_S   t0, 0(a0)
                REG_S   t1, SZREG(a0)

                addi    a0, a0, 2 * SZREG
                addi    a1, a1, 2 * SZREG
                bne     a2, a0, 1b
        .endm

#endif  /* __ASM_ASSEMBLER_H */

#if defined(VDSO_CFI) && (__riscv_xlen == 64)
.macro vdso_lpad, label = 0
lpad \label
.endm
#else
.macro vdso_lpad, label = 0
.endm
#endif

/*
 * This macro emits a program property note section identifying
 * architecture features which require special handling, mainly for
 * use in assembly files included in the VDSO.
 */
#define NT_GNU_PROPERTY_TYPE_0  5
#define GNU_PROPERTY_RISCV_FEATURE_1_AND 0xc0000000

#define GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP            BIT(0)
#define GNU_PROPERTY_RISCV_FEATURE_1_ZICFISS            BIT(1)

#if defined(VDSO_CFI) && (__riscv_xlen == 64)
#define GNU_PROPERTY_RISCV_FEATURE_1_DEFAULT \
        (GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP | GNU_PROPERTY_RISCV_FEATURE_1_ZICFISS)
#endif

#ifdef GNU_PROPERTY_RISCV_FEATURE_1_DEFAULT
.macro emit_riscv_feature_1_and, feat = GNU_PROPERTY_RISCV_FEATURE_1_DEFAULT
        .pushsection .note.gnu.property, "a"
        .p2align        3
        .word           4
        .word           16
        .word           NT_GNU_PROPERTY_TYPE_0
        .asciz          "GNU"
        .word           GNU_PROPERTY_RISCV_FEATURE_1_AND
        .word           4
        .word           \feat
        .word           0
        .popsection
.endm
#else
.macro emit_riscv_feature_1_and, feat = 0
.endm
#endif