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Revision 1.1.1.1 (vendor branch), Tue Mar 4 16:15:12 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)

/*
 * Written by J.T. Conklin <jtc@netbsd.org>.
 * Public domain.
 * Adapted for NetBSD/x86_64 by Frank van der Linden <fvdl@wasabisystems.com>
 */

#include <machine/asm.h>

#if defined(LIBC_SCCS)
	RCSID("$NetBSD: memcmp.S,v 1.1 2001/06/19 00:22:46 fvdl Exp $")
#endif

ENTRY(memcmp)
	cld				/* set compare direction forward */
	movq	%rdx,%rcx		/* compare by longs */
	shrq	$3,%rcx
	repe
	cmpsq
	jne	L5			/* do we match so far? */

	movq	%rdx,%rcx		/* compare remainder by bytes */
	andq	$7,%rcx
	repe
	cmpsb
	jne	L6			/* do we match? */

	xorl	%eax,%eax		/* we match, return zero	*/
	ret

L5:	movl	$8,%ecx			/* We know that one of the next	*/
	subq	%rcx,%rdi		/* eight pairs of bytes do not	*/
	subq	%rcx,%rsi		/* match.			*/
	repe
	cmpsb
L6:	xorl	%eax,%eax		/* Perform unsigned comparison	*/
	movb	-1(%rdi),%al
	xorl	%edx,%edx
	movb	-1(%rsi),%dl
	subl    %edx,%eax
	ret