* 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
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. */
leal boot_stack_end(%ebp), %esp
#ifdef CONFIG_RELOCATABLE
movl %ebp, %ebx
+
+#ifdef CONFIG_EFI_STUB
+/*
+ * If we were loaded via the EFI LoadImage service, startup_32 will be at an
+ * offset to the start of the space allocated for the image. efi_pe_entry will
+ * set up image_offset to tell us where the image actually starts, so that we
+ * can use the full available buffer.
+ * image_offset = startup_32 - image_base
+ * Otherwise image_offset will be zero and has no effect on the calculations.
+ */
+ subl image_offset(%ebp), %ebx
+#endif
+
movl BP_kernel_alignment(%esi), %eax
decl %eax
addl %eax, %ebx
notl %eax
andl %eax, %ebx
cmpl $LOAD_PHYSICAL_ADDR, %ebx
- jge 1f
+ jae 1f
#endif
movl $LOAD_PHYSICAL_ADDR, %ebx
1:
/* Target address to relocate to for decompression */
- movl BP_init_size(%esi), %eax
- subl $_end, %eax
- addl %eax, %ebx
+ addl BP_init_size(%esi), %ebx
+ subl $_end, %ebx
/*
* 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
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
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
* and command line.
*/
+ cld
+ cli
+
/* Setup data segments. */
xorl %eax, %eax
movl %eax, %ds
/* Start with the delta to where the kernel will run at. */
#ifdef CONFIG_RELOCATABLE
leaq startup_32(%rip) /* - $startup_32 */, %rbp
+
+#ifdef CONFIG_EFI_STUB
+/*
+ * If we were loaded via the EFI LoadImage service, startup_32 will be at an
+ * offset to the start of the space allocated for the image. efi_pe_entry will
+ * set up image_offset to tell us where the image actually starts, so that we
+ * can use the full available buffer.
+ * image_offset = startup_32 - image_base
+ * Otherwise image_offset will be zero and has no effect on the calculations.
+ */
+ movl image_offset(%rip), %eax
+ subq %rax, %rbp
+#endif
+
movl BP_kernel_alignment(%rsi), %eax
decl %eax
addq %rax, %rbp
notq %rax
andq %rax, %rbp
cmpq $LOAD_PHYSICAL_ADDR, %rbp
- jge 1f
+ jae 1f
#endif
movq $LOAD_PHYSICAL_ADDR, %rbp
1:
*/
/* 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
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
+ leaq gdt(%rbx), %rdx
+ movq %rdx, 2(%rax)
+ lgdt (%rax)
+
/*
* Jump to the relocated address.
*/
SYM_FUNC_START(efi64_stub_entry)
SYM_FUNC_START_ALIAS(efi_stub_entry)
and $~0xf, %rsp /* realign the stack */
+ movq %rdx, %rbx /* save boot_params pointer */
call efi_main
- movq %rax,%rsi
- movl BP_code32_start(%esi), %eax
+ movq %rbx,%rsi
leaq startup_64(%rax), %rax
jmp *%rax
SYM_FUNC_END(efi64_stub_entry)
leaq input_data(%rip), %rdx /* input_data */
movl $z_input_len, %ecx /* input_len */
movq %rbp, %r8 /* output target address */
- movq $z_output_len, %r9 /* decompressed length, end of relocs */
+ movl $z_output_len, %r9d /* decompressed length, end of relocs */
call extract_kernel /* returns kernel location in %rax */
popq %rsi
.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 */
.quad 0x0000000000000000 /* TS continued */
SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end)
+#ifdef CONFIG_EFI_STUB
+SYM_DATA(image_offset, .long 0)
+#endif
+
#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)
+/*
+ * efi_status_t efi32_pe_entry(efi_handle_t image_handle,
+ * efi_system_table_32_t *sys_table)
+ */
+
+ pushl %ebp
+ movl %esp, %ebp
+ pushl %eax // dummy push to allocate loaded_image
+
+ pushl %ebx // save callee-save registers
+ pushl %edi
+
+ call verify_cpu // check for long mode support
+ testl %eax, %eax
+ movl $0x80000003, %eax // EFI_UNSUPPORTED
+ jnz 2f
+
+ call 1f
+1: pop %ebx
+ subl $1b, %ebx
+
+ /* Get the loaded image protocol pointer from the image handle */
+ leal -4(%ebp), %eax
+ pushl %eax // &loaded_image
+ leal loaded_image_proto(%ebx), %eax
+ pushl %eax // pass the GUID address
+ pushl 8(%ebp) // pass the image handle
+
+ /*
+ * Note the alignment of the stack frame.
+ * sys_table
+ * handle <-- 16-byte aligned on entry by ABI
+ * return address
+ * frame pointer
+ * loaded_image <-- local variable
+ * saved %ebx <-- 16-byte aligned here
+ * saved %edi
+ * &loaded_image
+ * &loaded_image_proto
+ * handle <-- 16-byte aligned for call to handle_protocol
+ */
+
+ movl 12(%ebp), %eax // sys_table
+ movl ST32_boottime(%eax), %eax // sys_table->boottime
+ call *BS32_handle_protocol(%eax) // sys_table->boottime->handle_protocol
+ addl $12, %esp // restore argument space
+ testl %eax, %eax
+ jnz 2f
+
+ movl 8(%ebp), %ecx // image_handle
+ movl 12(%ebp), %edx // sys_table
+ movl -4(%ebp), %esi // loaded_image
+ movl LI32_image_base(%esi), %esi // loaded_image->image_base
+ movl %ebx, %ebp // startup_32 for efi32_pe_stub_entry
+ /*
+ * We need to set the image_offset variable here since startup_32() will
+ * use it before we get to the 64-bit efi_pe_entry() in C code.
+ */
+ subl %esi, %ebx
+ movl %ebx, image_offset(%ebp) // save image_offset
+ jmp efi32_pe_stub_entry
+
+2: popl %edi // restore callee-save registers
+ popl %ebx
+ leave
+ ret
+SYM_FUNC_END(efi32_pe_entry)
+
+ .section ".rodata"
+ /* EFI loaded image protocol GUID */
+ .balign 4
+SYM_DATA_START_LOCAL(loaded_image_proto)
+ .long 0x5b1b31a1
+ .word 0x9562, 0x11d2
+ .byte 0x8e, 0x3f, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b
+SYM_DATA_END(loaded_image_proto)
#endif
/*
/*
* Space for page tables (not in .bss so not zeroed)
*/
- .section ".pgtable","a",@nobits
+ .section ".pgtable","aw",@nobits
.balign 4096
SYM_DATA_LOCAL(pgtable, .fill BOOT_PGT_SIZE, 1, 0)
projects / linux.git / commitdiff