linux-stable/arch/riscv/kernel/hibernate-asm.S
Song Shuai c6399b8930
riscv: hibernation: Remove duplicate call of suspend_restore_csrs
The suspend_restore_csrs is called in both __hibernate_cpu_resume
and the `else` of subsequent swsusp_arch_suspend.

Removing the first call makes both suspend_{save,restore}_csrs
left in swsusp_arch_suspend for clean code.

Fixes: c031721001 ("RISC-V: Add arch functions to support hibernation/suspend-to-disk")
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: JeeHeng Sia <jeeheng.sia@starfivetech.com>
Signed-off-by: Song Shuai <songshuaishuai@tinylab.org>
Link: https://lore.kernel.org/r/20230522025020.285042-1-songshuaishuai@tinylab.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-19 09:27:57 -07:00

76 lines
1.6 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Hibernation low level support for RISCV.
*
* Copyright (C) 2023 StarFive Technology Co., Ltd.
*
* Author: Jee Heng Sia <jeeheng.sia@starfivetech.com>
*/
#include <asm/asm.h>
#include <asm/asm-offsets.h>
#include <asm/assembler.h>
#include <asm/csr.h>
#include <linux/linkage.h>
/*
* int __hibernate_cpu_resume(void)
* Switch back to the hibernated image's page table prior to restoring the CPU
* context.
*
* Always returns 0
*/
ENTRY(__hibernate_cpu_resume)
/* switch to hibernated image's page table. */
csrw CSR_SATP, s0
sfence.vma
REG_L a0, hibernate_cpu_context
suspend_restore_regs
/* Return zero value. */
mv a0, zero
ret
END(__hibernate_cpu_resume)
/*
* Prepare to restore the image.
* a0: satp of saved page tables.
* a1: satp of temporary page tables.
* a2: cpu_resume.
*/
ENTRY(hibernate_restore_image)
mv s0, a0
mv s1, a1
mv s2, a2
REG_L s4, restore_pblist
REG_L a1, relocated_restore_code
jr a1
END(hibernate_restore_image)
/*
* The below code will be executed from a 'safe' page.
* It first switches to the temporary page table, then starts to copy the pages
* back to the original memory location. Finally, it jumps to __hibernate_cpu_resume()
* to restore the CPU context.
*/
ENTRY(hibernate_core_restore_code)
/* switch to temp page table. */
csrw satp, s1
sfence.vma
.Lcopy:
/* The below code will restore the hibernated image. */
REG_L a1, HIBERN_PBE_ADDR(s4)
REG_L a0, HIBERN_PBE_ORIG(s4)
copy_page a0, a1
REG_L s4, HIBERN_PBE_NEXT(s4)
bnez s4, .Lcopy
jr s2
END(hibernate_core_restore_code)