sconst.inc

这是《自己动手写操作系统》的原文件和代码

; ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
;                               sconst.inc
; ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
;                                                     Forrest Yu, 2005
; ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

P_STACKBASE	equ	0
GSREG		equ	P_STACKBASE
FSREG		equ	GSREG		+ 4
ESREG		equ	FSREG		+ 4
DSREG		equ	ESREG		+ 4
EDIREG		equ	DSREG		+ 4
ESIREG		equ	EDIREG		+ 4
EBPREG		equ	ESIREG		+ 4
KERNELESPREG	equ	EBPREG		+ 4
EBXREG		equ	KERNELESPREG	+ 4
EDXREG		equ	EBXREG		+ 4
ECXREG		equ	EDXREG		+ 4
EAXREG		equ	ECXREG		+ 4
RETADR		equ	EAXREG		+ 4
EIPREG		equ	RETADR		+ 4
CSREG		equ	EIPREG		+ 4
EFLAGSREG	equ	CSREG		+ 4
ESPREG		equ	EFLAGSREG	+ 4
SSREG		equ	ESPREG		+ 4
P_STACKTOP	equ	SSREG		+ 4
P_LDT_SEL	equ	P_STACKTOP
P_LDT		equ	P_LDT_SEL	+ 4

TSS3_S_SP0	equ	4

INT_M_CTL	equ	0x20	; I/O port for interrupt controller         <Master>
INT_M_CTLMASK	equ	0x21	; setting bits in this port disables ints   <Master>
INT_S_CTL	equ	0xA0	; I/O port for second interrupt controller  <Slave>
INT_S_CTLMASK	equ	0xA1	; setting bits in this port disables ints   <Slave>

EOI		equ	0x20

; 以下选择子值必须与 protect.h 中保持一致!!!
SELECTOR_FLAT_C		equ		0x08		; LOADER 里面已经确定了的.
SELECTOR_TSS		equ		0x20		; TSS. 从外层跳到内存时 SS 和 ESP 的值从里面获得.
SELECTOR_KERNEL_CS	equ		SELECTOR_FLAT_C