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Revision 1.1.1.1 (vendor branch), Tue Mar 4 16:15:05 2008 UTC (16 years, 2 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: ffs.c,v 1.7 2004/11/28 07:23:41 mickey Exp $	*/

/*
 * Public domain.
 * Written by Dale Rahn.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$OpenBSD: ffs.c,v 1.7 2004/11/28 07:23:41 mickey Exp $";
#endif /* LIBC_SCCS and not lint */

#if !defined(_KERNEL) && !defined(_STANDALONE)
#include <string.h>
#else
#include <lib/libkern/libkern.h>
#endif

/*
 * ffs -- vax ffs instruction
 */
int
ffs(int mask)
{
	int bit;
	unsigned int r = mask;
	static const signed char t[16] = {
		-28, 1, 2, 1,
		  3, 1, 2, 1,
		  4, 1, 2, 1,
		  3, 1, 2, 1
	};

	bit = 0;
	if (!(r & 0xffff)) {
		bit += 16;
		r >>= 16;
	}
	if (!(r & 0xff)) {
		bit += 8;
		r >>= 8;
	}
	if (!(r & 0xf)) {
		bit += 4;
		r >>= 4;
	}

	return (bit + t[ r & 0xf ]);
}