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Revision 1.1.1.1 (vendor branch), Tue Mar 4 16:15:13 2008 UTC (16 years, 4 months ago) by nbrk
Branch: OPENBSD_4_2_BASE, MAIN
CVS Tags: jornada-partial-support-wip, HEAD
Changes since 1.1: +0 -0 lines 

Import of OpenBSD 4.2 release kernel tree with initial code to support 
Jornada 720/728, StrongARM 1110-based handheld PC.
At this point kernel roots on NFS and boots into vfs_mountroot() and traps.
What is supported:
- glass console, Jornada framebuffer (jfb) works in 16bpp direct color mode
(needs some palette tweaks for non black/white/blue colors, i think)
- saic, SA11x0 interrupt controller (needs cleanup)
- sacom, SA11x0 UART (supported only as boot console for now)
- SA11x0 GPIO controller fully supported (but can't handle multiple interrupt
handlers on one gpio pin)
- sassp, SSP port on SA11x0 that attaches spibus
- Jornada microcontroller (jmcu) to control kbd, battery, etc throught
the SPI bus (wskbd attaches on jmcu, but not tested)
- tod functions seem work
- initial code for SA-1111 (chip companion) : this is TODO

Next important steps, i think:
- gpio and intc on sa1111
- pcmcia support for sa11x0 (and sa1111 help logic)
- REAL root on nfs when we have PCMCIA support (we may use any of supported pccard NICs)
- root on wd0! (using already supported PCMCIA-ATA)

/*	$OpenBSD: bzero.S,v 1.3 2007/05/25 20:32:29 krw Exp $	*/

/*
 * Written by J.T. Conklin <jtc@netbsd.org>.
 * Public domain.
 */

#include <machine/asm.h>

ENTRY(bzero)
	pushl	%edi
	movl	8(%esp),%edi
	movl	12(%esp),%edx

	cld				/* set fill direction forward */
	xorl	%eax,%eax		/* set fill data to 0 */

	/*
	 * if the string is too short, it's really not worth the overhead
	 * of aligning to word boundaries, etc.  So we jump to a plain
	 * unaligned set.
	 */
	cmpl	$16,%edx
	jb	L1

	movl	%edi,%ecx		/* compute misalignment */
	negl	%ecx
	andl	$3,%ecx
	subl	%ecx,%edx
	rep				/* zero until word aligned */
	stosb

	movl	%edx,%ecx		/* zero by words */
	shrl	$2,%ecx
	andl	$3,%edx
	rep
	stosl

L1:	movl	%edx,%ecx		/* zero remainder by bytes */
	rep
	stosb

	popl	%edi
	ret