~kris/9p

9hist

ref: 5f2a65731e6b8719e39a418354a8be588374e214 9hist/pc/l.s -rw-r--r-- 1.8 KiB
5f2a6573 — David du Colombier Plan 9 from Bell Labs 1991-06-25 35 years ago 
                                                                                
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#include "mem.h"

GLOBL	gdtptr(SB),$6

	DATA	gdtptr+0(SB)/2, $(6*8)
	DATA	gdtptr+2(SB)/4, $gdt(SB)

/*
 *  boot processor
 */
TEXT	start(SB),$0

	CLI			/* disable interrupts */
	MOVW	$NULLSEL,IDTR	/* force shutdown on error */

	/* point data segment at low memory */
	XORL	AX,AX
	MOVW	AX,DS

	/* load gdt address (valid after paging) */
	LEAL	gdtptr(SB),AX
	MOVL	-KZERO(AX),GDTR

	CALL	main(SB)
	/* never returns */

/*
 *  first 16 ``standard'' traps
 */
TEXT	trap0(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$0
	JMP	alltrap

TEXT	trap1(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$1
	JMP	alltrap

TEXT	trap2(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$2
	JMP	alltrap

TEXT	trap3(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$3
	JMP	alltrap

TEXT	trap4(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$4
	JMP	alltrap

TEXT	trap5(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$5
	JMP	alltrap

TEXT	trap6(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$6
	JMP	alltrap

TEXT	trap7(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$7
	JMP	alltrap

TEXT	trap8(SB),$0

	PUSHL	$8
	JMP	alltrap

TEXT	trap9(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$9
	JMP	alltrap

TEXT	trap10(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$10
	JMP	alltrap

TEXT	trap11(SB),$0

	PUSHL	$11
	JMP	alltrap

TEXT	trap12(SB),$0

	PUSHL	$12
	JMP	alltrap

TEXT	trap13(SB),$0

	PUSHL	$13
	JMP	alltrap

TEXT	trap14(SB),$0

	PUSHL	$14
	JMP	alltrap

TEXT	trap15(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$15
	JMP	alltrap

/*
 *  invalid trap
 */
TEXT	invtrap(SB),$0

	PUSHL	$0	/* put on an error code */
	PUSHL	$16
	JMP	alltrap

/*
 *  common trap code
 */
alltrap:

	PUSHL	DS
	PUSHAL
	MOVL	$KDSEL, AX
	MOVW	AX, DS
	CALL	trap(SB)
	POPAL
	POPL	DS
	ADDL	$8,SP		/* pop the trap and error codes */
	IRETL