diff options
Diffstat (limited to 'arch/x86/boot/compressed/head_64.S')
| -rw-r--r-- | arch/x86/boot/compressed/head_64.S | 125 |
1 files changed, 96 insertions, 29 deletions
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 1f1f6c8139b3..f7bacc4c1494 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -53,19 +53,7 @@ SYM_FUNC_START(startup_32) * all need to be under the 4G limit. */ cld - /* - * Test KEEP_SEGMENTS flag to see if the bootloader is asking - * us to not reload segments - */ - testb $KEEP_SEGMENTS, BP_loadflags(%esi) - jnz 1f - cli - movl $(__BOOT_DS), %eax - movl %eax, %ds - movl %eax, %es - movl %eax, %ss -1: /* * Calculate the delta between where we were compiled to run @@ -80,10 +68,21 @@ SYM_FUNC_START(startup_32) 1: popl %ebp subl $1b, %ebp + /* Load new GDT with the 64bit segments using 32bit descriptor */ + leal gdt(%ebp), %eax + movl %eax, 2(%eax) + lgdt (%eax) + + /* Load segment registers with our descriptors */ + movl $__BOOT_DS, %eax + movl %eax, %ds + movl %eax, %es + movl %eax, %fs + movl %eax, %gs + movl %eax, %ss + /* setup a stack and make sure cpu supports long mode. */ - movl $boot_stack_end, %eax - addl %ebp, %eax - movl %eax, %esp + leal boot_stack_end(%ebp), %esp call verify_cpu testl %eax, %eax @@ -120,10 +119,6 @@ SYM_FUNC_START(startup_32) * Prepare for entering 64 bit mode */ - /* Load new GDT with the 64bit segments using 32bit descriptor */ - addl %ebp, gdt+2(%ebp) - lgdt gdt(%ebp) - /* Enable PAE mode */ movl %cr4, %eax orl $X86_CR4_PAE, %eax @@ -212,8 +207,13 @@ SYM_FUNC_START(startup_32) cmp $0, %edi jz 1f leal efi64_stub_entry(%ebp), %eax - movl %esi, %edx movl efi32_boot_args+4(%ebp), %esi + movl efi32_boot_args+8(%ebp), %edx // saved bootparams pointer + cmpl $0, %edx + jnz 1f + leal efi_pe_entry(%ebp), %eax + movl %edi, %ecx // MS calling convention + movl %esi, %edx 1: #endif pushl %eax @@ -238,11 +238,17 @@ SYM_FUNC_START(efi32_stub_entry) 1: pop %ebp subl $1b, %ebp + movl %esi, efi32_boot_args+8(%ebp) +SYM_INNER_LABEL(efi32_pe_stub_entry, SYM_L_LOCAL) movl %ecx, efi32_boot_args(%ebp) movl %edx, efi32_boot_args+4(%ebp) - sgdtl efi32_boot_gdt(%ebp) movb $0, efi_is64(%ebp) + /* Save firmware GDTR and code/data selectors */ + sgdtl efi32_boot_gdt(%ebp) + movw %cs, efi32_boot_cs(%ebp) + movw %ds, efi32_boot_ds(%ebp) + /* Disable paging */ movl %cr0, %eax btrl $X86_CR0_PG_BIT, %eax @@ -266,6 +272,9 @@ SYM_CODE_START(startup_64) * and command line. */ + cld + cli + /* Setup data segments. */ xorl %eax, %eax movl %eax, %ds @@ -354,9 +363,9 @@ SYM_CODE_START(startup_64) */ /* Make sure we have GDT with 32-bit code segment */ - leaq gdt(%rip), %rax - movq %rax, gdt64+2(%rip) - lgdt gdt64(%rip) + leaq gdt64(%rip), %rax + addq %rax, 2(%rax) + lgdt (%rax) /* * paging_prepare() sets up the trampoline and checks if we need to @@ -441,6 +450,16 @@ trampoline_return: cld popq %rsi + /* + * The GDT may get overwritten either during the copy we just did or + * during extract_kernel below. To avoid any issues, repoint the GDTR + * to the new copy of the GDT. + */ + leaq gdt64(%rbx), %rax + subq %rbp, 2(%rax) + addq %rbx, 2(%rax) + lgdt (%rax) + /* * Jump to the relocated address. */ @@ -613,13 +632,13 @@ SYM_FUNC_END(.Lno_longmode) .data SYM_DATA_START_LOCAL(gdt64) - .word gdt_end - gdt - .quad 0 + .word gdt_end - gdt - 1 + .quad gdt - gdt64 SYM_DATA_END(gdt64) .balign 8 SYM_DATA_START_LOCAL(gdt) - .word gdt_end - gdt - .long gdt + .word gdt_end - gdt - 1 + .long 0 .word 0 .quad 0x00cf9a000000ffff /* __KERNEL32_CS */ .quad 0x00af9a000000ffff /* __KERNEL_CS */ @@ -629,8 +648,56 @@ SYM_DATA_START_LOCAL(gdt) SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end) #ifdef CONFIG_EFI_MIXED -SYM_DATA_LOCAL(efi32_boot_args, .long 0, 0) +SYM_DATA_LOCAL(efi32_boot_args, .long 0, 0, 0) SYM_DATA(efi_is64, .byte 1) + +#define ST32_boottime 60 // offsetof(efi_system_table_32_t, boottime) +#define BS32_handle_protocol 88 // offsetof(efi_boot_services_32_t, handle_protocol) +#define LI32_image_base 32 // offsetof(efi_loaded_image_32_t, image_base) + + .text + .code32 +SYM_FUNC_START(efi32_pe_entry) + pushl %ebp + + call verify_cpu // check for long mode support + testl %eax, %eax + movl $0x80000003, %eax // EFI_UNSUPPORTED + jnz 3f + + call 1f +1: pop %ebp + subl $1b, %ebp + + /* Get the loaded image protocol pointer from the image handle */ + subl $12, %esp // space for the loaded image pointer + pushl %esp // pass its address + leal 4f(%ebp), %eax + pushl %eax // pass the GUID address + pushl 28(%esp) // pass the image handle + + movl 36(%esp), %eax // sys_table + movl ST32_boottime(%eax), %eax // sys_table->boottime + call *BS32_handle_protocol(%eax) // sys_table->boottime->handle_protocol + cmp $0, %eax + jnz 2f + + movl 32(%esp), %ecx // image_handle + movl 36(%esp), %edx // sys_table + movl 12(%esp), %esi // loaded_image + movl LI32_image_base(%esi), %esi // loaded_image->image_base + jmp efi32_pe_stub_entry + +2: addl $24, %esp +3: popl %ebp + ret +SYM_FUNC_END(efi32_pe_entry) + + .section ".rodata" + /* EFI loaded image protocol GUID */ +4: .long 0x5B1B31A1 + .word 0x9562, 0x11d2 + .byte 0x8E, 0x3F, 0x00, 0xA0, 0xC9, 0x69, 0x72, 0x3B #endif /* |