From e3cc5f6c89ba9f37bf2c1edf588d0f75c1d63c57 Mon Sep 17 00:00:00 2001 From: Michal Idziorek Date: Fri, 14 Nov 2014 11:08:04 +0100 Subject: rename dirs --- boot2/pm.asm | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 boot2/pm.asm (limited to 'boot2/pm.asm') diff --git a/boot2/pm.asm b/boot2/pm.asm new file mode 100644 index 0000000..e6f3474 --- /dev/null +++ b/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 -- cgit v1.2.3