Import backup from 2005-11-01

kernel/boot.asm

@@ -89,10 +89,7 @@ segmented_start:
 	mov	ecx, _rm_params			; put real mode params here (video mode etc...)
 	sub	ecx, VIRT_OFFSET
 	
-	mov	eax, cr0
+	jmp	0xC0005010			; jump to rmmod
-	and	eax, 0x7FFFFFFE			; leave PM
-	mov	cr0, eax
-	jmp	0x0:0x5010			; jump to rmmod
 
 ;Next we enable paging with the first 4mb mapped 1:1 virtual:physical
 ; and with the 4mb starting at 0xC000_0000 mapped to the first 4mb physical.
@@ -191,12 +188,12 @@ idle_loop:					; system idle loop
 gdtrbs32:
 	dw	gdt_endbs32-gdtbs32-1
 	dd	gdtbs32-VIRT_OFFSET
-gdtbs32:				;null descriptor
+gdtbs32:			; 0 = null descriptor
 	dd	0
 	dd	0
 
 	;a base of 0x4000_0000, when added to 0xC000_0000 will produce 0x0000_0000 physical before paging in effect
-KERNEL_CODE_BS32 equ $-gdtbs32
+KERNEL_CODE_BS32 equ $-gdtbs32	; 8
 	db	0xff		;limit	7:0
 	db	0xff		;limit	15:8
 	db	0x00		;base	7:0
@@ -206,7 +203,7 @@ KERNEL_CODE_BS32 equ $-gdtbs32
 	db	0xcf		;flags / limit 19:16
 	db	0x40		;base	31:24
 
-KERNEL_DATA_BS32 equ $-gdtbs32
+KERNEL_DATA_BS32 equ $-gdtbs32	; 16
 	db	0xff		;limit	7:0
 	db	0xff		;limit	15:8
 	db	0x00		;base	7:0
@@ -216,6 +213,22 @@ KERNEL_DATA_BS32 equ $-gdtbs32
 	db	0xcf		;flags / limit 19:16
 	db	0x40		;base	31:24
 
+KERNEL_CODE_BS6_ equ $-gdtbs32	; 24
+	dw	0xffff		;limit 15:0
+	dw	0x0000		;base  15:0
+	db	0x00		;base  23:16
+	db	0x9A		;access ([P][DPL][1][Executable][Direction/Conforming][Writable/Readable][A])
+	db	0x00		;flags ([G][D/B][0][0]) / limit 19:16
+	db	0x00		;base  31:24
+
+KERNEL_DATA_BS16 equ $-gdtbs32	; 32
+	dw	0xffff		;limit 15:0
+	dw	0x0000		;base  15:0
+	db	0x00		;base  23:16
+	db	0x92		;access ([P][DPL][1][Executable][Direction/Conforming][Writable/Readable][A])
+	db	0x00		;flags ([G][D/B][0][0]) / limit 19:16
+	db	0x00		;base  31:24
+
 gdt_endbs32:
 
 %include "gdt.inc"

kernel/gdt.inc

@@ -6,11 +6,11 @@
 gdtr:
 	dw	gdt_end-gdt-1
 	dd	GDT_V
-gdt:
+gdt:			; 0
 	dd	0
 	dd	0
 
-KERNEL_CODE equ $-gdt
+KERNEL_CODE equ $-gdt	; 8
 	dw	0xffff	;limit 15:0
 	dw	0x0000	;base  15:0
 	db	0x00	;base  23:16
@@ -18,7 +18,7 @@ KERNEL_CODE equ $-gdt
 	db	0xCF	;flags ([G][D/B][0][0]) / limit 19:16
 	db	0x00	;base  31:24
 
-KERNEL_DATA equ $-gdt
+KERNEL_DATA equ $-gdt	; 16
 	dw	0xffff	;limit 15:0
 	dw	0x0000	;base  15:0
 	db	0x00	;base  23:16
@@ -27,7 +27,7 @@ KERNEL_DATA equ $-gdt
 	db	0x00	;base  31:24
 
 
-USER_CODE equ $-gdt
+USER_CODE equ $-gdt	; 24
 	dw	0xffff	;limit 15:0
 	dw	0x0000	;base  15:0
 	db	0x00	;base  23:16
@@ -35,7 +35,7 @@ USER_CODE equ $-gdt
 	db	0xCF	;flags ([G][D/B][0][0]) / limit 19:16
 	db	0x00	;base  31:24
 
-USER_DATA equ $-gdt
+USER_DATA equ $-gdt	; 32
 	dw	0xffff	;limit 15:0
 	dw	0x0000	;base  15:0
 	db	0x00	;base  23:16
@@ -43,7 +43,7 @@ USER_DATA equ $-gdt
 	db	0xCF	;flags ([G][D/B][0][0]) / limit 19:16
 	db	0x00	;base  31:24
 
-TSS0_SEG equ $-gdt
+TSS0_SEG equ $-gdt	; 40
 	dw	0x67	;limit 15:0
 	dw	0	;base  15:0
 	db	0	;base  23:16

rmmod/rmmod.asm

@@ -10,7 +10,7 @@
 
 ; the bootstrap process will jump us to 0x0:0x5010 so we'd better be ready for it
 [org 0x5000]
-[bits 16]
+[bits 32]
 			;HOS module header, better be 16 bytes!
 	dd	0x4D534F48	; magic identifier "HOSM"
 	dd	1		; real mode module
@@ -20,10 +20,16 @@
 ; ebx = return address
 ; ecx = where to store real mode parameter table
 start:
-	jmp blah
+	jmp	24:start_pm16
-blah:
+[bits 16]
-	jmp $
+start_pm16:					; in 16-bit protected mode
-	jmp	0:start_refreshed
+	mov	ax, 32
+	mov	ss, ax
+	mov	eax, cr0
+	and	eax, 0x7FFFFFFE
+	mov	cr0, eax			; leave PM
+	
+	jmp	0:start_refreshed		; enter RM
 
 %include "conio.inc"
 %include "vesa.inc"