getidprom.s

来自「操作系统SunOS 4.1.3版本的源码」· S 代码 · 共 32 行

/*
 *	.seg	"data"
 *	.asciz	"@(#)getidprom.s 1.1 92/07/30"
 *	Copyright (c) 1986 by Sun Microsystems, Inc.
 */
 	.seg	"text"
 	.align	4

IDPROMBASE=0x00000000		! base address of idprom in CTL space
IDPROMSIZE=0x20			! size of idprom
ASI_CTL=2			! address space indentifier for CTL space
!
! getidprom(addr, size)
!
! Read the ID prom.
! This is mapped from IDPROMBASE for IDPROMSIZE bytes in the
! ASI_CTL address space for byte access only.
! 
	.global _getidprom
_getidprom:
	set     IDPROMBASE, %g1
	clr     %g2
1:
	lduba   [%g1 + %g2]ASI_CTL, %g7 ! get id prom byte
	add     %g2, 1, %g2		! interlock
	stb     %g7, [%o0]		! put it out
	cmp     %g2, %o1		! done yet?
	bne,a   1b
	add     %o0, 1, %o0		! delay slot
	retl				! leaf routine return
	lduba   [%g1]ASI_CTL, %o0	! return id prom format byte