[BACK]Return to memset.S CVS log [TXT][DIR] Up to [local] / sys / lib / libkern / arch / amd64

File: [local] / sys / lib / libkern / arch / amd64 / memset.S (download)

Revision 1.1.1.1 (vendor branch), Tue Mar 4 16:15:12 2008 UTC (16 years, 3 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: memset.S,v 1.1 2001/06/19 00:22:46 fvdl Exp $")
#endif

ENTRY(memset)
	movq	%rsi,%rax
	movq	%rdx,%rcx
	movq	%rdi,%r11

	cld				/* set fill direction forward */

	/*
	 * 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.
	 */
	cmpq	$0x0f,%rcx
	jle	L1

	movb	%al,%ah			/* copy char to all bytes in word */
	movl	%eax,%edx
	sall	$16,%eax
	orl	%edx,%eax

	movl	%eax,%edx
	salq	$32,%rax
	orq	%rdx,%rax

	movq	%rdi,%rdx		/* compute misalignment */
	negq	%rdx
	andq	$7,%rdx
	movq	%rcx,%r8
	subq	%rdx,%r8

	movq	%rdx,%rcx		/* set until word aligned */
	rep
	stosb

	movq	%r8,%rcx
	shrq	$3,%rcx			/* set by words */
	rep
	stosq

	movq	%r8,%rcx		/* set remainder by bytes */
	andq	$7,%rcx
L1:	rep
	stosb
	movq	%r11,%rax

	ret