18c2ecf20Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */ 28c2ecf20Sopenharmony_ci/* 38c2ecf20Sopenharmony_ci * This may not use any stack, nor any variable that is not "NoSave": 48c2ecf20Sopenharmony_ci * 58c2ecf20Sopenharmony_ci * Its rewriting one kernel image with another. What is stack in "old" 68c2ecf20Sopenharmony_ci * image could very well be data page in "new" image, and overwriting 78c2ecf20Sopenharmony_ci * your own stack under you is bad idea. 88c2ecf20Sopenharmony_ci */ 98c2ecf20Sopenharmony_ci 108c2ecf20Sopenharmony_ci#include <linux/linkage.h> 118c2ecf20Sopenharmony_ci#include <asm/segment.h> 128c2ecf20Sopenharmony_ci#include <asm/page_types.h> 138c2ecf20Sopenharmony_ci#include <asm/asm-offsets.h> 148c2ecf20Sopenharmony_ci#include <asm/processor-flags.h> 158c2ecf20Sopenharmony_ci#include <asm/frame.h> 168c2ecf20Sopenharmony_ci 178c2ecf20Sopenharmony_ci.text 188c2ecf20Sopenharmony_ci 198c2ecf20Sopenharmony_ciSYM_FUNC_START(swsusp_arch_suspend) 208c2ecf20Sopenharmony_ci movl %esp, saved_context_esp 218c2ecf20Sopenharmony_ci movl %ebx, saved_context_ebx 228c2ecf20Sopenharmony_ci movl %ebp, saved_context_ebp 238c2ecf20Sopenharmony_ci movl %esi, saved_context_esi 248c2ecf20Sopenharmony_ci movl %edi, saved_context_edi 258c2ecf20Sopenharmony_ci pushfl 268c2ecf20Sopenharmony_ci popl saved_context_eflags 278c2ecf20Sopenharmony_ci 288c2ecf20Sopenharmony_ci /* save cr3 */ 298c2ecf20Sopenharmony_ci movl %cr3, %eax 308c2ecf20Sopenharmony_ci movl %eax, restore_cr3 318c2ecf20Sopenharmony_ci 328c2ecf20Sopenharmony_ci FRAME_BEGIN 338c2ecf20Sopenharmony_ci call swsusp_save 348c2ecf20Sopenharmony_ci FRAME_END 358c2ecf20Sopenharmony_ci RET 368c2ecf20Sopenharmony_ciSYM_FUNC_END(swsusp_arch_suspend) 378c2ecf20Sopenharmony_ci 388c2ecf20Sopenharmony_ciSYM_CODE_START(restore_image) 398c2ecf20Sopenharmony_ci /* prepare to jump to the image kernel */ 408c2ecf20Sopenharmony_ci movl restore_jump_address, %ebx 418c2ecf20Sopenharmony_ci movl restore_cr3, %ebp 428c2ecf20Sopenharmony_ci 438c2ecf20Sopenharmony_ci movl mmu_cr4_features, %ecx 448c2ecf20Sopenharmony_ci 458c2ecf20Sopenharmony_ci /* jump to relocated restore code */ 468c2ecf20Sopenharmony_ci movl relocated_restore_code, %eax 478c2ecf20Sopenharmony_ci jmpl *%eax 488c2ecf20Sopenharmony_ciSYM_CODE_END(restore_image) 498c2ecf20Sopenharmony_ci 508c2ecf20Sopenharmony_ci/* code below has been relocated to a safe page */ 518c2ecf20Sopenharmony_ciSYM_CODE_START(core_restore_code) 528c2ecf20Sopenharmony_ci movl temp_pgt, %eax 538c2ecf20Sopenharmony_ci movl %eax, %cr3 548c2ecf20Sopenharmony_ci 558c2ecf20Sopenharmony_ci jecxz 1f # cr4 Pentium and higher, skip if zero 568c2ecf20Sopenharmony_ci andl $~(X86_CR4_PGE), %ecx 578c2ecf20Sopenharmony_ci movl %ecx, %cr4; # turn off PGE 588c2ecf20Sopenharmony_ci movl %cr3, %eax; # flush TLB 598c2ecf20Sopenharmony_ci movl %eax, %cr3 608c2ecf20Sopenharmony_ci1: 618c2ecf20Sopenharmony_ci movl restore_pblist, %edx 628c2ecf20Sopenharmony_ci .p2align 4,,7 638c2ecf20Sopenharmony_ci 648c2ecf20Sopenharmony_cicopy_loop: 658c2ecf20Sopenharmony_ci testl %edx, %edx 668c2ecf20Sopenharmony_ci jz done 678c2ecf20Sopenharmony_ci 688c2ecf20Sopenharmony_ci movl pbe_address(%edx), %esi 698c2ecf20Sopenharmony_ci movl pbe_orig_address(%edx), %edi 708c2ecf20Sopenharmony_ci 718c2ecf20Sopenharmony_ci movl $(PAGE_SIZE >> 2), %ecx 728c2ecf20Sopenharmony_ci rep 738c2ecf20Sopenharmony_ci movsl 748c2ecf20Sopenharmony_ci 758c2ecf20Sopenharmony_ci movl pbe_next(%edx), %edx 768c2ecf20Sopenharmony_ci jmp copy_loop 778c2ecf20Sopenharmony_ci .p2align 4,,7 788c2ecf20Sopenharmony_ci 798c2ecf20Sopenharmony_cidone: 808c2ecf20Sopenharmony_ci jmpl *%ebx 818c2ecf20Sopenharmony_ciSYM_CODE_END(core_restore_code) 828c2ecf20Sopenharmony_ci 838c2ecf20Sopenharmony_ci /* code below belongs to the image kernel */ 848c2ecf20Sopenharmony_ci .align PAGE_SIZE 858c2ecf20Sopenharmony_ciSYM_FUNC_START(restore_registers) 868c2ecf20Sopenharmony_ci /* go back to the original page tables */ 878c2ecf20Sopenharmony_ci movl %ebp, %cr3 888c2ecf20Sopenharmony_ci movl mmu_cr4_features, %ecx 898c2ecf20Sopenharmony_ci jecxz 1f # cr4 Pentium and higher, skip if zero 908c2ecf20Sopenharmony_ci movl %ecx, %cr4; # turn PGE back on 918c2ecf20Sopenharmony_ci1: 928c2ecf20Sopenharmony_ci 938c2ecf20Sopenharmony_ci movl saved_context_esp, %esp 948c2ecf20Sopenharmony_ci movl saved_context_ebp, %ebp 958c2ecf20Sopenharmony_ci movl saved_context_ebx, %ebx 968c2ecf20Sopenharmony_ci movl saved_context_esi, %esi 978c2ecf20Sopenharmony_ci movl saved_context_edi, %edi 988c2ecf20Sopenharmony_ci 998c2ecf20Sopenharmony_ci pushl saved_context_eflags 1008c2ecf20Sopenharmony_ci popfl 1018c2ecf20Sopenharmony_ci 1028c2ecf20Sopenharmony_ci /* Saved in save_processor_state. */ 1038c2ecf20Sopenharmony_ci movl $saved_context, %eax 1048c2ecf20Sopenharmony_ci lgdt saved_context_gdt_desc(%eax) 1058c2ecf20Sopenharmony_ci 1068c2ecf20Sopenharmony_ci xorl %eax, %eax 1078c2ecf20Sopenharmony_ci 1088c2ecf20Sopenharmony_ci /* tell the hibernation core that we've just restored the memory */ 1098c2ecf20Sopenharmony_ci movl %eax, in_suspend 1108c2ecf20Sopenharmony_ci 1118c2ecf20Sopenharmony_ci RET 1128c2ecf20Sopenharmony_ciSYM_FUNC_END(restore_registers) 113