serenity/Kernel/Arch/i386/Boot/boot.S
Andreas Kling 5f610417d0 Kernel: Remove kprintf()
There are no remaining users of this API.
2021-02-17 16:33:43 +01:00

401 lines
9.4 KiB
ArmAsm

.set MULTIBOOT_MAGIC, 0x1badb002
.set MULTIBOOT_PAGE_ALIGN, 0x1
.set MULTIBOOT_MEMORY_INFO, 0x2
.set MULTIBOOT_VIDEO_MODE, 0x4
.set multiboot_flags, MULTIBOOT_PAGE_ALIGN | MULTIBOOT_MEMORY_INFO | MULTIBOOT_VIDEO_MODE
.set multiboot_checksum, -(MULTIBOOT_MAGIC + multiboot_flags)
.section .multiboot
.align 4
.long MULTIBOOT_MAGIC
.long multiboot_flags
.long multiboot_checksum
/* for MULTIBOOT_MEMORY_INFO */
.long 0x00000000 /* header_addr */
.long 0x00000000 /* load_addr */
.long 0x00000000 /* load_end_addr */
.long 0x00000000 /* bss_end_addr */
.long 0x00000000 /* entry_addr */
/* for MULTIBOOT_VIDEO_MODE */
.long 0x00000000 /* mode_type */
.long 1280 /* width */
.long 1024 /* height */
.long 32 /* depth */
.section .stack, "aw", @nobits
stack_bottom:
.skip 32768
stack_top:
.section .page_tables, "aw", @nobits
.align 4096
.global boot_pdpt
boot_pdpt:
.skip 4096
.global boot_pd0
boot_pd0:
.skip 4096
.global boot_pd3
boot_pd3:
.skip 4096
.global boot_pd0_pt0
boot_pd0_pt0:
.skip 4096 * 4
.global boot_pd3_pts
boot_pd3_pts:
.skip 4096 * 4
.global boot_pd3_pt1023
boot_pd3_pt1023:
.skip 4096
.section .text
.global start
.type start, @function
.extern init
.type init, @function
.extern multiboot_info_ptr
.type multiboot_info_ptr, @object
/*
construct the following (32-bit PAE) page table layout:
pdpt
0: boot_pd0 (0-1GB)
1: n/a (1-2GB)
2: n/a (2-3GB)
3: boot_pd3 (3-4GB)
boot_pd0 : 512 pde's
0: boot_pd0_pt0 (0-2MB) (id 512 4KB pages)
boot_pd3 : 512 pde's
0: boot_pd3_pts[0] (3072-3074MB) (pseudo 512 4KB pages)
1: boot_pd3_pts[1] (3074-3076MB) (pseudo 512 4KB pages)
2: boot_pd3_pts[2] (3076-3078MB) (pseudo 512 4KB pages)
3: boot_pd3_pts[3] (3078-3080MB) (pseudo 512 4KB pages)
4: boot_pd3_pt1023 (4094-4096MB) (for page table mappings)
the 9 page tables each contain 512 pte's that map individual 4KB pages
*/
start:
cli
cld
/* clear pdpt */
movl $(boot_pdpt - 0xc0000000), %edi
movl $1024, %ecx
xorl %eax, %eax
rep stosl
/* set up pdpt[0] and pdpt[3] */
movl $(boot_pdpt - 0xc0000000), %edi
movl $((boot_pd0 - 0xc0000000) + 1), 0(%edi)
movl $((boot_pd3 - 0xc0000000) + 1), 24(%edi)
/* clear pd0 */
movl $(boot_pd0 - 0xc0000000), %edi
movl $1024, %ecx
xorl %eax, %eax
rep stosl
/* clear pd3 */
movl $(boot_pd3 - 0xc0000000), %edi
movl $1024, %ecx
xorl %eax, %eax
rep stosl
/* clear pd0's pt's */
movl $(boot_pd0_pt0 - 0xc0000000), %edi
movl $(1024 * 4), %ecx
xorl %eax, %eax
rep stosl
/* clear pd3's pt's */
movl $(boot_pd3_pts - 0xc0000000), %edi
movl $(1024 * 5), %ecx
xorl %eax, %eax
rep stosl
/* add boot_pd0_pt0 to boot_pd0 */
movl $(boot_pd0 - 0xc0000000), %edi
movl $(boot_pd0_pt0 - 0xc0000000), %eax
movl %eax, 0(%edi)
/* R/W + Present */
orl $0x3, 0(%edi)
/* add boot_pd3_pts to boot_pd3 */
movl $4, %ecx
movl $(boot_pd3 - 0xc0000000), %edi
movl $(boot_pd3_pts - 0xc0000000), %eax
1:
movl %eax, 0(%edi)
/* R/W + Present */
orl $0x3, 0(%edi)
addl $8, %edi
addl $4096, %eax
loop 1b
/* identity map the 0 to 2MB range */
movl $512, %ecx
movl $(boot_pd0_pt0 - 0xc0000000), %edi
xorl %eax, %eax
1:
movl %eax, 0(%edi)
/* R/W + Present */
orl $0x3, 0(%edi)
addl $8, %edi
addl $4096, %eax
loop 1b
/* pseudo identity map the 3072-3080MB range */
movl $(512 * 4), %ecx
movl $(boot_pd3_pts - 0xc0000000), %edi
xorl %eax, %eax
1:
movl %eax, 0(%edi)
/* R/W + Present */
orl $0x3, 0(%edi)
addl $8, %edi
addl $4096, %eax
loop 1b
/* create an empty page table for the top 2MB at the 4GB mark */
movl $(boot_pd3 - 0xc0000000), %edi
movl $(boot_pd3_pt1023 - 0xc0000000), 4088(%edi)
orl $0x3, 4088(%edi)
movl $0, 4092(%edi)
/* point CR3 to PDPT */
movl $(boot_pdpt - 0xc0000000), %eax
movl %eax, %cr3
/* enable PAE + PSE */
movl %cr4, %eax
orl $0x60, %eax
movl %eax, %cr4
/* enable PG */
movl %cr0, %eax
orl $0x80000000, %eax
movl %eax, %cr0
/* set up stack */
mov $stack_top, %esp
and $-16, %esp
/* jmp to an address above the 3GB mark */
movl $1f,%eax
jmp *%eax
1:
movl %cr3, %eax
movl %eax, %cr3
/* unmap the 0-1MB range, which isn't used after jmp-ing up here */
movl $256, %ecx
movl $(boot_pd0_pt0 - 0xc0000000), %edi
xorl %eax, %eax
1:
movl %eax, 0(%edi)
addl $8, %edi
loop 1b
/* jump into C++ land */
addl $0xc0000000, %ebx
movl %ebx, multiboot_info_ptr
call init
add $4, %esp
cli
loop:
hlt
jmp loop
.extern init_ap
.type init_ap, @function
/*
The apic_ap_start function will be loaded to P0x00008000 where the APIC
will boot the AP from in real mode. This code also contains space for
special variables that *must* remain here. When initializing the APIC,
the code here gets copied to P0x00008000, the variables in here get
populated and then the the boot of the APs will be triggered. Having
the variables here allows us to access them from real mode. Also, the
code here avoids the need for relocation entries.
Basically, the variables between apic_ap_start and end_apic_ap_start
*MUST* remain here and cannot be moved into a .bss or any other location.
*/
.global apic_ap_start
.type apic_ap_start, @function
apic_ap_start:
.code16
cli
jmp $0x800, $(1f - apic_ap_start) /* avoid relocation entries */
1:
mov %cs, %ax
mov %ax, %ds
xor %ax, %ax
mov %ax, %sp
/* load the first temporary gdt */
lgdt (ap_cpu_gdtr_initial - apic_ap_start)
/* enable PM */
movl %cr0, %eax
orl $1, %eax
movl %eax, %cr0
ljmpl $8, $(apic_ap_start32 - apic_ap_start + 0x8000)
apic_ap_start32:
.code32
mov $0x10, %ax
mov %ax, %ss
mov %ax, %ds
mov %ax, %es
mov %ax, %fs
mov %ax, %gs
movl $0x8000, %ebp
/* generate a unique ap cpu id (0 means 1st ap, not bsp!) */
xorl %eax, %eax
incl %eax
lock; xaddl %eax, (ap_cpu_id - apic_ap_start)(%ebp) /* avoid relocation entries */
movl %eax, %esi
/* find our allocated stack based on the generated id */
movl (ap_cpu_init_stacks - apic_ap_start)(%ebp, %eax, 4), %esp
/* check if we support NX and enable it if we do */
movl $0x80000001, %eax
cpuid
testl $0x100000, %edx
je (1f - apic_ap_start + 0x8000)
/* turn on IA32_EFER.NXE */
movl $0xc0000080, %ecx
rdmsr
orl $0x800, %eax
wrmsr
1:
/* load the bsp's cr3 value */
movl (ap_cpu_init_cr3 - apic_ap_start)(%ebp), %eax
movl %eax, %cr3
/* enable PAE + PSE */
movl %cr4, %eax
orl $0x60, %eax
movl %eax, %cr4
/* enable PG */
movl %cr0, %eax
orl $0x80000000, %eax
movl %eax, %cr0
/* load a second temporary gdt that points above 3GB */
lgdt (ap_cpu_gdtr_initial2 - apic_ap_start + 0xc0008000)
/* jump above 3GB into our identity mapped area now */
ljmp $8, $(apic_ap_start32_2 - apic_ap_start + 0xc0008000)
apic_ap_start32_2:
/* flush the TLB */
movl %cr3, %eax
movl %eax, %cr3
movl $0xc0008000, %ebp
/* now load the final gdt and idt from the identity mapped area */
movl (ap_cpu_gdtr - apic_ap_start)(%ebp), %eax
lgdt (%eax)
movl (ap_cpu_idtr - apic_ap_start)(%ebp), %eax
lidt (%eax)
/* set same cr0 and cr4 values as the BSP */
movl (ap_cpu_init_cr0 - apic_ap_start)(%ebp), %eax
movl %eax, %cr0
movl (ap_cpu_init_cr4 - apic_ap_start)(%ebp), %eax
movl %eax, %cr4
/* push the Processor pointer this CPU is going to use */
movl (ap_cpu_init_processor_info_array - apic_ap_start)(%ebp), %eax
addl $0xc0000000, %eax
movl 0(%eax, %esi, 4), %eax
push %eax
/* push the cpu id, 0 representing the bsp and call into c++ */
incl %esi
push %esi
xor %ebp, %ebp
cld
/* We are in identity mapped P0x8000 and the BSP will unload this code
once all APs are initialized, so call init_ap but return to our
infinite loop */
push $loop
ljmp $8, $init_ap
.align 4
.global apic_ap_start_size
apic_ap_start_size:
.2byte end_apic_ap_start - apic_ap_start
ap_cpu_id:
.4byte 0x0
ap_cpu_gdt:
/* null */
.8byte 0x0
/* code */
.4byte 0x0000FFFF
.4byte 0x00cf9a00
/* data */
.4byte 0x0000FFFF
.4byte 0x00cf9200
ap_cpu_gdt_end:
ap_cpu_gdtr_initial:
.2byte ap_cpu_gdt_end - ap_cpu_gdt - 1
.4byte (ap_cpu_gdt - apic_ap_start) + 0x8000
ap_cpu_gdtr_initial2:
.2byte ap_cpu_gdt_end - ap_cpu_gdt - 1
.4byte (ap_cpu_gdt - apic_ap_start) + 0xc0008000
.global ap_cpu_gdtr
ap_cpu_gdtr:
.4byte 0x0 /* will be set at runtime */
.global ap_cpu_idtr
ap_cpu_idtr:
.4byte 0x0 /* will be set at runtime */
.global ap_cpu_init_cr0
ap_cpu_init_cr0:
.4byte 0x0 /* will be set at runtime */
.global ap_cpu_init_cr3
ap_cpu_init_cr3:
.4byte 0x0 /* will be set at runtime */
.global ap_cpu_init_cr4
ap_cpu_init_cr4:
.4byte 0x0 /* will be set at runtime */
.global ap_cpu_init_processor_info_array
ap_cpu_init_processor_info_array:
.4byte 0x0 /* will be set at runtime */
.global ap_cpu_init_stacks
ap_cpu_init_stacks:
/* array of allocated stack pointers */
/* NOTE: ap_cpu_init_stacks must be the last variable before
end_apic_ap_start! */
.set end_apic_ap_start, .