| 26,10 → 26,11 |
|---|
| # THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| # |
| |
| .section K_TEXT_START |
| .global kernel_image_start |
| #include <arch/mm/ptl.h> |
| |
| .code16 |
| #define START_STACK 0x7c00 |
| #define START_STACK_64 $0xffffffff80007c00 |
| |
| # |
| # This is where we require any SPARTAN-kernel-compatible boot loader |
| # to pass control in real mode. |
| 38,14 → 39,17 |
|---|
| # time. So we can just load the respective table registers and |
| # switch to protected mode. |
| # |
| .section K_TEXT_START |
| .code16 |
| .global kernel_image_start |
| kernel_image_start: |
| cli |
| xorw %ax,%ax |
| movw %ax,%ds |
| movw %ax,%ss # initialize stack segment register |
| movl $0x7c00,%esp # initialize stack pointer |
| movl START_STACK,%esp # initialize stack pointer |
| |
| call memmap_arch_init |
| # call memmap_arch_init |
| |
| mov $0x80000000, %eax |
| cpuid |
| 56,38 → 60,99 |
|---|
| bt $29, %edx # Test if long mode is supported. |
| jnc no_long_mode |
| |
| # Fill out GDTR.base, IDTR.base |
| leal gdtr, %eax |
| movl gdt_addr, %ebx |
| movl %ebx, 2(%eax) |
| # Load gdtr, idtr |
| lgdt gdtr_inst |
| lidt idtr_inst |
| |
| movl %cr0,%eax |
| orl $0x1,%eax |
| movl %eax,%cr0 # switch to protected mode |
| |
| movl idt_addr, %ebx |
| leal idtr, %eax |
| movl %ebx, 2(%eax) |
| jmpl $40, $now_in_prot |
| |
| # Load gdtr, idtr |
| lgdt gdtr |
| lidt idtr |
| no_long_mode: |
| 1: |
| jmp 1b |
| |
| # Protected 16-bit. We want to reuse the code-seg descriptor, |
| # the Default operand size must not be 1 when entering long mode |
| now_in_prot: |
| # Set up stack & data descriptors |
| movw $16, %ax |
| movw %ax, %ds |
| movw %ax, %fs |
| movw %ax, %gs |
| movw %ax, %ss |
| |
| # Enable 64-bit page transaltion entries - CR4.PAE = 1. |
| # Paging is not enabled until after long mode is enabled |
| movl %cr4, %eax |
| btsl $5, %eax |
| movl %eax, %cr4 |
| |
| # Set up paging tables |
| leal ptl_0, %eax |
| movl %eax, %cr3 |
| |
| # Enable long mode |
| movl $0xc0000080, %ecx # EFER MSR number |
| rdmsr # Read EFER |
| btsl $8, %eax # Set LME=1 |
| wrmsr # Write EFER |
| |
| mov $1, %eax # Enable protected mode (CR0.PE = 1) |
| mov %eax, %cr0 |
| # Enable paging to activate long mode (set CR0.PG=1) |
| movl %cr0, %eax |
| btsl $31, %eax |
| movl %eax, %cr0 |
| |
| # At this point we are in compatibility mode |
| jmpl $8, $start64 |
| |
| jmpl $8, $now_in_prot |
| .code64 |
| start64: |
| movq START_STACK_64, %rsp |
| |
| now_in_prot: |
| lidt idtr_inst |
| |
| |
| no_long_mode: |
| call main_bsp # never returns |
| 1: |
| jmp 1b |
| |
| |
| .section K_DATA_START |
| .section K_DATA_START |
| .align 4096 |
| page_directory: |
| .space 4096, 0 |
| .global ptl_2 |
| ptl_2: |
| .quad 0x0 | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE) |
| .quad 0x200000 | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE) |
| .quad 0x400000 | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE) |
| .quad 0x600000 | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE) |
| .quad 0x800000 | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE) |
| .quad 0xa00000 | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE) |
| .quad 0xc00000 | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE) |
| .quad 0xe00000 | (PTL_WRITABLE | PTL_PRESENT | PTL_2MB_PAGE) |
| |
| .align 4096 |
| .global ptl_1 |
| ptl_1: |
| .quad ptl_2 + (PTL_WRITABLE | PTL_PRESENT) |
| .fill 509,8,0 |
| .quad ptl_2 + (PTL_WRITABLE | PTL_PRESENT) |
| .fill 2,8,0 |
| |
| .align 4096 |
| .global ptl_0 |
| ptl_0: |
| .quad ptl_1 + (PTL_WRITABLE | PTL_PRESENT) |
| .fill 510,8,0 |
| .quad ptl_1 + (PTL_WRITABLE | PTL_PRESENT) |
| |
| gdt_addr: |
| .quad gdt + 0x80000000 |
| idt_addr: |
| .quad idt + 0x80000000 |
| .global gdtr_inst |
| gdtr_inst: |
| .word 7*8 # GDT_ITEMS * 8 |
| .long gdt + 0x80000000 |
| |
| .global idtr_inst |
| idtr_inst: |
| .word 0 |
| .long idt + 0x80000000 |