diff options
Diffstat (limited to 'xxx/boot2/pm.asm')
| -rw-r--r-- | xxx/boot2/pm.asm | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/xxx/boot2/pm.asm b/xxx/boot2/pm.asm new file mode 100644 index 0000000..e6f3474 --- /dev/null +++ b/xxx/boot2/pm.asm @@ -0,0 +1,36 @@ +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;;;;;;; Miguel's FoolOS Helper Functions ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +; +; switch_to_pm - actual switch from 16bit real to 32bit protected +; init_pm - sets up some regs and calls boot_32_pm +; + +[bits 16] +switch_to_pm: + + cli ;switch off interrupts! + lgdt [gdt_descriptor] ;load descriptor table! +; lldt [gdt_descriptor] ;load descriptor table! (local) + + ;switch on 32-bit protected mode + mov eax, cr0 + or eax,0x1 + mov cr0, eax + + jmp CODE_SEG:init_pm + +[bits 32] +init_pm: + + mov ax, DATA_SEG + mov ds, ax + mov ss, ax + mov es, ax + mov fs, ax + mov gs, ax + + mov ebp, 0x07bff + mov esp, ebp + + call boot_32_pm ;continue booting in 32-bit protected mode |