RISC-V: Add arch functions to support hibernation/suspend-to-disk

2023-04-29T18:25:13+00:00

Low level Arch functions were created to support hibernation. swsusp_arch_suspend() relies code from __cpu_suspend_enter() to write cpu state onto the stack, then calling swsusp_save() to save the memory image. Arch specific hibernation header is implemented and is utilized by the arch_hibernation_header_restore() and arch_hibernation_header_save() functions. The arch specific hibernation header consists of satp, hartid, and the cpu_resume address. The kernel built version is also need to be saved into the hibernation image header to making sure only the same kernel is restore when resume. swsusp_arch_resume() creates a temporary page table that covering only the linear map. It copies the restore code to a 'safe' page, then start to restore the memory image. Once completed, it restores the original kernel's page table. It then calls into __hibernate_cpu_resume() to restore the CPU context. Finally, it follows the normal hibernation path back to the hibernation core. To enable hibernation/suspend to disk into RISCV, the below config need to be enabled: - CONFIG_HIBERNATION - CONFIG_ARCH_HIBERNATION_HEADER - CONFIG_ARCH_HIBERNATION_POSSIBLE Signed-off-by: Sia Jee Heng Reviewed-by: Ley Foon Tan Reviewed-by: Mason Huo Reviewed-by: Conor Dooley Reviewed-by: Andrew Jones Link: https://lore.kernel.org/r/20230330064321.1008373-5-jeeheng.sia@starfivetech.com Signed-off-by: Palmer Dabbelt

RISC-V: Factor out common code of __cpu_resume_enter()

2023-04-29T18:25:11+00:00

The cpu_resume() function is very similar for the suspend to disk and suspend to ram cases. Factor out the common code into suspend_restore_csrs macro and suspend_restore_regs macro. Signed-off-by: Sia Jee Heng Reviewed-by: Andrew Jones Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20230330064321.1008373-3-jeeheng.sia@starfivetech.com Signed-off-by: Palmer Dabbelt

kernel/linux.git/arch/riscv/include/asm/assembler.h, branch v6.12.80

RISC-V: Add arch functions to support hibernation/suspend-to-disk

RISC-V: Factor out common code of __cpu_resume_enter()