| /* SPDX-License-Identifier: GPL-2.0 */ |
| .text |
| #include <linux/linkage.h> |
| #include <asm/segment.h> |
| #include <asm/page.h> |
| #include <asm/pgtable_32.h> |
| |
| .macro writepost,value |
| movb $0x34, %al |
| outb %al, $0x70 |
| movb $\value, %al |
| outb %al, $0x71 |
| .endm |
| |
| wakeup_start: |
| # OFW lands us here, running in protected mode, with a |
| # kernel-compatible GDT already setup. |
| |
| # Clear any dangerous flags |
| pushl $0 |
| popfl |
| |
| writepost 0x31 |
| |
| # Set up %cr3 |
| movl $initial_page_table - __PAGE_OFFSET, %eax |
| movl %eax, %cr3 |
| |
| movl saved_cr4, %eax |
| movl %eax, %cr4 |
| |
| movl saved_cr0, %eax |
| movl %eax, %cr0 |
| |
| # Control registers were modified, pipeline resync is needed |
| jmp 1f |
| 1: |
| |
| movw $__KERNEL_DS, %ax |
| movw %ax, %ss |
| movw %ax, %ds |
| movw %ax, %es |
| movw %ax, %fs |
| movw %ax, %gs |
| |
| lgdt saved_gdt |
| lidt saved_idt |
| lldt saved_ldt |
| ljmp $(__KERNEL_CS),$1f |
| 1: |
| movl %cr3, %eax |
| movl %eax, %cr3 |
| wbinvd |
| |
| # Go back to the return point |
| jmp ret_point |
| |
| save_registers: |
| sgdt saved_gdt |
| sidt saved_idt |
| sldt saved_ldt |
| |
| pushl %edx |
| movl %cr4, %edx |
| movl %edx, saved_cr4 |
| |
| movl %cr0, %edx |
| movl %edx, saved_cr0 |
| |
| popl %edx |
| |
| movl %ebx, saved_context_ebx |
| movl %ebp, saved_context_ebp |
| movl %esi, saved_context_esi |
| movl %edi, saved_context_edi |
| |
| pushfl |
| popl saved_context_eflags |
| |
| ret |
| |
| restore_registers: |
| movl saved_context_ebp, %ebp |
| movl saved_context_ebx, %ebx |
| movl saved_context_esi, %esi |
| movl saved_context_edi, %edi |
| |
| pushl saved_context_eflags |
| popfl |
| |
| ret |
| |
| SYM_CODE_START(do_olpc_suspend_lowlevel) |
| call save_processor_state |
| call save_registers |
| |
| # This is the stack context we want to remember |
| movl %esp, saved_context_esp |
| |
| pushl $3 |
| call xo1_do_sleep |
| |
| jmp wakeup_start |
| .p2align 4,,7 |
| ret_point: |
| movl saved_context_esp, %esp |
| |
| writepost 0x32 |
| |
| call restore_registers |
| call restore_processor_state |
| ret |
| SYM_CODE_END(do_olpc_suspend_lowlevel) |
| |
| .data |
| saved_gdt: .long 0,0 |
| saved_idt: .long 0,0 |
| saved_ldt: .long 0 |
| saved_cr4: .long 0 |
| saved_cr0: .long 0 |
| saved_context_esp: .long 0 |
| saved_context_edi: .long 0 |
| saved_context_esi: .long 0 |
| saved_context_ebx: .long 0 |
| saved_context_ebp: .long 0 |
| saved_context_eflags: .long 0 |
