Load ELF kernel instead of flat binary

[nameless-os.git] / boot / x86 / stage3 / loader.s

diff --git a/boot/x86/stage3/loader.s b/boot/x86/stage3/loader.s
index b89d9245f62bad488bec74ca13bd80000db7806c..87598f4b0c93a6d95cbb1aa21dcf6a87723ff1da 100644 (file)
--- a/boot/x86/stage3/loader.s
+++ b/boot/x86/stage3/loader.s
@@ -1,7 +1,9 @@
 bits 16
 cpu 686
-org 0x1800
 
+extern run_kernel
+
+section .text
 %include "../fat32/fat32-structs.s"
 
 %macro print 1
@@ -11,10 +13,14 @@ org 0x1800
        pop si
 %endmacro
 
+extern __STACK_BOTTOM__
+
+global _start
 _start:
+       mov sp, __STACK_BOTTOM__
        mov [BOOT_DRIVE], dl
        call enable_unreal
-       print string
+       print begin
        call check_a20
        jc .a20_enabled
        call enable_a20
@@ -55,13 +61,24 @@ _start:
        pop si
        pop cx
        print kernel_found
+       mov eax, [es:di+dir_entry.filesize]
+       mov [KERNEL_SIZE], eax
        mov ax, [es:di+dir_entry.firstclushi]
        shl eax, 16
-       mov ax, [es:di+(dir_entry.firstcluslo)]
+       mov ax, [es:di+dir_entry.firstcluslo]
        call print_dword
        mov edi, 0x100000
+       print kernel_loading
        call read_clus_chain_unreal ; load kernel
+       print kernel_loaded
        
+       call get_e820_map
+       mov ebx, ecx
+       mov eax, 24
+       mul ecx
+       add eax, 20
+       sub sp, ax
+
        cli
        lgdt [gdt]
        mov eax, cr0
@@ -143,32 +160,43 @@ memcpy:
        pop esi
        ret
 
-
 %include "unreal.s"
 %include "a20.s"
 %include "../fat32/fat32.s"
 %include "gdt.s"
 %include "print.s"
+%include "e820.s"
 
-in_protected:
 bits 32
+section .text
+in_protected:
        mov ax, 0x10
        mov ds, ax
        mov es, ax
        mov ss, ax
        mov fs, ax
        mov gs, ax
-       call 0x100000
-       hlt
-       jmp $-1
 
-kernel_name: db "KERNEL  BIN"
-string: db "Hello from LOADER.BIN!", 0xd, 0xa, 0
-a20_enabled: db "A20 is enabled", 0xd, 0xa, 0
+       push dword [KERNEL_SIZE]
+       push 0x100000
+       push ebx
+       push edi
+       call run_kernel
+
+section .bss
+KERNEL_SIZE: resd 1
+
+section .rodata
+
+kernel_name: db "KERNEL  ELF"
+begin: db "Nameless Bootloader revision ", GIT_REVISION, 0xd, 0xa, 0
+a20_enabled: db "A20 has been enabled", 0xd, 0xa, "Searching for kernel...", 0xd, 0xa, 0
 a20_fail: db "Failed to enable A20, giving up!", 0xd, 0xa, 0
 crit_err: db "A critical error occurred, dumping registers now: ", 0xd, 0xa, 0
 kernel_found: db "Found kernel at cluster ", 0
-missing_kernel: db "Could not find KERNEL.BIN", 0xd, 0xa, 0
+kernel_loading: db 0xd, 0xa, "Loading kernel...", 0xd, 0xa, 0
+kernel_loaded: db "Kernel successfully loaded.", 0xd, 0xa, "Setting up kernel environment and running kernel...", 0xd, 0xa, 0
+missing_kernel: db "Could not find KERNEL.ELF", 0xd, 0xa, 0
 eax_s: db "EAX: ", 0
 ebx_s: db "EBX: ", 0
 ecx_s: db "ECX: ", 0