machdep.c

早期freebsd实现

	/*
	 * fuword failed (bogus sc_ap value).
	 */
	if (flags == -1)
		return (EINVAL);
	if (flags == 0 || copyin((caddr_t)rf, (caddr_t)&tstate, sizeof tstate))
		return (EJUSTRETURN);
#ifdef DEBUG
	if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
		printf("sigreturn(%d): ssp %x usp %x scp %x ft %d\n",
		       p->p_pid, &flags, scp->sc_sp, uap->sigcntxp,
		       (flags&SS_RTEFRAME) ? tstate.ss_frame.f_format : -1);
#endif
	/*
	 * Restore most of the users registers except for A6 and SP
	 * which were handled above.
	 */
	if (flags & SS_USERREGS)
		bcopy((caddr_t)tstate.ss_frame.f_regs,
		      (caddr_t)frame->f_regs, sizeof(frame->f_regs)-2*NBPW);
	/*
	 * Restore long stack frames.  Note that we do not copy
	 * back the saved SR or PC, they were picked up above from
	 * the sigcontext structure.
	 */
	if (flags & SS_RTEFRAME) {
		register int sz;
		
		/* grab frame type and validate */
		sz = tstate.ss_frame.f_format;
		if (sz > 15 || (sz = exframesize[sz]) < 0)
			return (EINVAL);
		frame->f_stackadj -= sz;
		frame->f_format = tstate.ss_frame.f_format;
		frame->f_vector = tstate.ss_frame.f_vector;
		bcopy((caddr_t)&tstate.ss_frame.F_u, (caddr_t)&frame->F_u, sz);
#ifdef DEBUG
		if (sigdebug & SDB_FOLLOW)
			printf("sigreturn(%d): copy in %d of frame type %d\n",
			       p->p_pid, sz, tstate.ss_frame.f_format);
#endif
	}
#ifdef FPCOPROC
	/*
	 * Finally we restore the original FP context
	 */
	if (flags & SS_FPSTATE)
		m68881_restore(&tstate.ss_fpstate);
#ifdef DEBUG
	if ((sigdebug & SDB_FPSTATE) && *(char *)&tstate.ss_fpstate)
		printf("sigreturn(%d): copied in FP state (%x) at %x\n",
		       p->p_pid, *(u_int *)&tstate.ss_fpstate,
		       &tstate.ss_fpstate);
#endif
#endif
#ifdef DEBUG
	if ((sigdebug & SDB_FOLLOW) ||
	    ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid))
		printf("sigreturn(%d): returns\n", p->p_pid);
#endif
	return (EJUSTRETURN);
}

int	waittime = -1;

boot(howto)
	register int howto;
{
	/* take a snap shot before clobbering any registers */
	if (curproc)
		savectx(curproc->p_addr, 0);

	boothowto = howto;
	if ((howto&RB_NOSYNC) == 0 && waittime < 0) {
		register struct buf *bp;
		int iter, nbusy;

		waittime = 0;
		(void) spl0();
		printf("syncing disks... ");
		/*
		 * Release vnodes held by texts before sync.
		 */
		if (panicstr == 0)
			vnode_pager_umount(NULL);
#ifdef notdef
#include "fd.h"
#if NFD > 0
		fdshutdown();
#endif
#endif
		sync(&proc0, (void *)NULL, (int *)NULL);

		for (iter = 0; iter < 20; iter++) {
			nbusy = 0;
			for (bp = &buf[nbuf]; --bp >= buf; )
				if ((bp->b_flags & (B_BUSY|B_INVAL)) == B_BUSY)
					nbusy++;
			if (nbusy == 0)
				break;
			printf("%d ", nbusy);
			DELAY(40000 * iter);
		}
		if (nbusy)
			printf("giving up\n");
		else
			printf("done\n");

		/*
		 * If we've been adjusting the clock, the todr
		 * will be out of synch; adjust it now.
		 */
		resettodr();
	}
	splhigh();			/* extreme priority */
	if (howto&RB_HALT) {
		printf("halted\n\n");
		asm("	stop	#0x2700");
	} else {
		printf("\r\n\n");
		if (howto & RB_DUMP)
			dumpsys();
		doboot();
		/*NOTREACHED*/
	}
	/*NOTREACHED*/
}

int	dumpmag = 0x8fca0101;	/* magic number for savecore */
int	dumpsize = 0;		/* also for savecore */
long	dumplo = 0;

dumpconf()
{
	int nblks;

	dumpsize = physmem;
	if (dumpdev != NODEV && bdevsw[major(dumpdev)].d_psize) {
		nblks = (*bdevsw[major(dumpdev)].d_psize)(dumpdev);
		if (dumpsize > btoc(dbtob(nblks - dumplo)))
			dumpsize = btoc(dbtob(nblks - dumplo));
		else if (dumplo == 0)
			dumplo = nblks - btodb(ctob(physmem));
	}
	/*
	 * Don't dump on the first CLBYTES (why CLBYTES?)
	 * in case the dump device includes a disk label.
	 */
	if (dumplo < btodb(CLBYTES))
		dumplo = btodb(CLBYTES);
}

/*
 * Doadump comes here after turning off memory management and
 * getting on the dump stack, either when called above, or by
 * the auto-restart code.
 */
dumpsys()
{

	msgbufmapped = 0;
	if (dumpdev == NODEV)
		return;
	/*
	 * For dumps during autoconfiguration,
	 * if dump device has already configured...
	 */
	if (dumpsize == 0)
		dumpconf();
	if (dumplo < 0)
		return;
	printf("\ndumping to dev %x, offset %d\n", dumpdev, dumplo);
	printf("dump ");
	switch ((*bdevsw[major(dumpdev)].d_dump)(dumpdev)) {

	case ENXIO:
		printf("device bad\n");
		break;

	case EFAULT:
		printf("device not ready\n");
		break;

	case EINVAL:
		printf("area improper\n");
		break;

	case EIO:
		printf("i/o error\n");
		break;

	default:
		printf("succeeded\n");
		break;
	}
}

/*
 * machine dependent system variables.
 */
cpu_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
	int *name;
	u_int namelen;
	void *oldp;
	size_t *oldlenp;
	void *newp;
	size_t newlen;
	struct proc *p;
{

	/* all sysctl names at this level are terminal */
	if (namelen != 1)
		return (ENOTDIR);		/* overloaded */

	switch (name[0]) {
	case CPU_CONSDEV:
		return (sysctl_rdstruct(oldp, oldlenp, newp, &cn_tty->t_dev,
		    sizeof cn_tty->t_dev));
	default:
		return (EOPNOTSUPP);
	}
	/* NOTREACHED */
}

initcpu()
{
#ifdef MAPPEDCOPY
	extern u_int mappedcopysize;

	/*
	 * Initialize lower bound for doing copyin/copyout using
	 * page mapping (if not already set).  We don't do this on
	 * VAC machines as it loses big time.
	 */
	if (mappedcopysize == 0) {
		if (ectype == EC_VIRT)
			mappedcopysize = (u_int) -1;
		else
			mappedcopysize = NBPG;
	}
#endif
	parityenable();
}

straytrap(pc, evec)
	int pc;
	u_short evec;
{
	printf("unexpected trap (vector offset %x) from %x\n",
	       evec & 0xFFF, pc);
}

int	*nofault;

badaddr(addr)
	register caddr_t addr;
{
	register int i;
	label_t	faultbuf;

#ifdef lint
	i = *addr; if (i) return(0);
#endif
	nofault = (int *) &faultbuf;
	if (setjmp((label_t *)nofault)) {
		nofault = (int *) 0;
		return(1);
	}
	i = *(volatile short *)addr;
	nofault = (int *) 0;
	return(0);
}

badbaddr(addr)
	register caddr_t addr;
{
	register int i;
	label_t	faultbuf;

#ifdef lint
	i = *addr; if (i) return(0);
#endif
	nofault = (int *) &faultbuf;
	if (setjmp((label_t *)nofault)) {
		nofault = (int *) 0;
		return(1);
	}
	i = *(volatile char *)addr;
	nofault = (int *) 0;
	return(0);
}

netintr()
{
#ifdef INET
	if (netisr & (1 << NETISR_ARP)) {
		netisr &= ~(1 << NETISR_ARP);
		arpintr();
	}
	if (netisr & (1 << NETISR_IP)) {
		netisr &= ~(1 << NETISR_IP);
		ipintr();
	}
#endif
#ifdef NS
	if (netisr & (1 << NETISR_NS)) {
		netisr &= ~(1 << NETISR_NS);
		nsintr();
	}
#endif
#ifdef ISO
	if (netisr & (1 << NETISR_ISO)) {
		netisr &= ~(1 << NETISR_ISO);
		clnlintr();
	}
#endif
#ifdef CCITT
	if (netisr & (1 << NETISR_CCITT)) {
		netisr &= ~(1 << NETISR_CCITT);
		ccittintr();
	}
#endif
}

#ifdef	notfdef
intrhand(sr)
	int sr;
{
	register struct isr *isr;
	register int found = 0;
	register int ipl;
	extern struct isr isrqueue[];

	ipl = (sr >> 8) & 7;
	switch (ipl) {

	case 3:
	case 4:
	case 5:
		ipl = ISRIPL(ipl);
		isr = isrqueue[ipl].isr_forw;
		for (; isr != &isrqueue[ipl]; isr = isr->isr_forw) {
			if ((isr->isr_intr)(isr->isr_arg)) {
				found++;
				break;
			}
		}
		if (found == 0)
			printf("stray interrupt, sr 0x%x\n", sr);
		break;

	case 0:
	case 1:
	case 2:
	case 6:
	case 7:
		printf("intrhand: unexpected sr 0x%x\n", sr);
		break;
	}
}
#endif

#if defined(DEBUG) && !defined(PANICBUTTON)
#define PANICBUTTON
#endif

#ifdef PANICBUTTON
int panicbutton = 1;	/* non-zero if panic buttons are enabled */
int crashandburn = 0;
int candbdelay = 50;	/* give em half a second */

void
candbtimer(arg)
	void *arg;
{

	crashandburn = 0;
}
#endif

/*
 * Level 7 interrupts can be caused by the keyboard or parity errors.
 */
nmihand(frame)
	struct frame frame;
{
#ifdef PANICBUTTON
       	static int innmihand = 0;

       	/*
       	 * Attempt to reduce the window of vulnerability for recursive
       	 * NMIs (e.g. someone holding down the keyboard reset button).
       	 */
       	if (innmihand == 0) {
       		innmihand = 1;
       		printf("Got a keyboard NMI\n");
       		innmihand = 0;
       	}
       	if (panicbutton) {
       		if (crashandburn) {
       			crashandburn = 0;
       			panic(panicstr ?
       			      "forced crash, nosync" : "forced crash");
       		}
       		crashandburn++;
       		timeout(candbtimer, (void *)0, candbdelay);
       	}
#endif
       	return;
}

regdump(fp, sbytes)
	struct frame *fp; /* must not be register */
	int sbytes;
{
	static int doingdump = 0;
	register int i;
	int s;
	extern char *hexstr();

	if (doingdump)
		return;
	s = splhigh();
	doingdump = 1;
	printf("pid = %d, pc = %s, ",
	       curproc ? curproc->p_pid : -1, hexstr(fp->f_pc, 8));
	printf("ps = %s, ", hexstr(fp->f_sr, 4));
	printf("sfc = %s, ", hexstr(getsfc(), 4));
	printf("dfc = %s\n", hexstr(getdfc(), 4));
	printf("Registers:\n     ");
	for (i = 0; i < 8; i++)
		printf("        %d", i);
	printf("\ndreg:");
	for (i = 0; i < 8; i++)
		printf(" %s", hexstr(fp->f_regs[i], 8));
	printf("\nareg:");
	for (i = 0; i < 8; i++)
		printf(" %s", hexstr(fp->f_regs[i+8], 8));
	if (sbytes > 0) {
		if (fp->f_sr & PSL_S) {
			printf("\n\nKernel stack (%s):",
			       hexstr((int)(((int *)&fp)-1), 8));
			dumpmem(((int *)&fp)-1, sbytes, 0);
		} else {
			printf("\n\nUser stack (%s):", hexstr(fp->f_regs[SP], 8));
			dumpmem((int *)fp->f_regs[SP], sbytes, 1);
		}
	}
	doingdump = 0;
	splx(s);
}

extern char kstack[];
#define KSADDR	((int *)&(kstack[(UPAGES-1)*NBPG]))

dumpmem(ptr, sz, ustack)
	register int *ptr;
	int sz;
{
	register int i, val;
	extern char *hexstr();

	for (i = 0; i < sz; i++) {
		if ((i & 7) == 0)
			printf("\n%s: ", hexstr((int)ptr, 6));
		else
			printf(" ");
		if (ustack == 1) {
			if ((val = fuword(ptr++)) == -1)
				break;
		} else {
			if (ustack == 0 &&
			    (ptr < KSADDR || ptr > KSADDR+(NBPG/4-1)))
				break;
			val = *ptr++;
		}
		printf("%s", hexstr(val, 8));
	}
	printf("\n");
}

char *
hexstr(val, len)
	register int val;
{
	static char nbuf[9];
	register int x, i;

	if (len > 8)
		return("");
	nbuf[len] = '\0';
	for (i = len-1; i >= 0; --i) {
		x = val & 0xF;
		if (x > 9)
			nbuf[i] = x - 10 + 'A';
		else
			nbuf[i] = x + '0';
		val >>= 4;
	}
	return(nbuf);
}

#ifdef DEBUG
char oflowmsg[] = "k-stack overflow";
char uflowmsg[] = "k-stack underflow";

badkstack(oflow, fr)
	int oflow;
	struct frame fr;
{
#ifdef	notdef
	extern char kstackatbase[];

	printf("%s: sp should be %x\n", 
	       oflow ? oflowmsg : uflowmsg,
	       kstackatbase - (exframesize[fr.f_format] + 8));
#endif
	printf("%s: sp should be ????????\n", oflow ? oflowmsg : uflowmsg);
	regdump(&fr, 0);
	panic(oflow ? oflowmsg : uflowmsg);
}
#endif

/* for LUNA */

/*
 * Enable parity detection
 */
#define PARREG		((volatile short *)0x49000003)
#define	PARITY_ENABLE	0xC
parityenable()
{
	*PARREG = PARITY_ENABLE;
}

#ifdef FPCOPROC
#define EXT_FPP_ADDR		0x6F000000	/* External 68882 board  */
#define INT_FPP_ADDR		0x6B000000	/* Internal 68881 chip   */

#define FPP_ON			0x80		/* selected fpp on	 */
#define FPP_OFF			0x00		/* selected fpp off    	 */

#define	SET_INT_FPP	(*(char *)INT_FPP_ADDR = FPP_ON);(*(char *)EXT_FPP_ADDR = FPP_OFF)
#define	SET_EXT_FPP	(*(char *)INT_FPP_ADDR = FPP_OFF);(*(char *)EXT_FPP_ADDR = FPP_ON)

#define	FPP68881	1
#define	FPP68882	2

unsigned char fpp_svarea[212];

#ifndef	OLD_LUNA
/*
 * Check FPP type 68881/68882.
 */

void checkfpp()
{
#ifdef LUNA2
	if (machineid == LUNA_II) {
		return;
	}
#endif
    SET_INT_FPP;	/* internal = on, external = off */
    if( is_68882() )
      fpptype = FPP68882;
    else
      fpptype = FPP68881;
    return;
}
#else

/*
 * Check in/ex-ternal fpp, and determine which we use.
 * Also set fpp type(MC68881/68882).
 */

void checkfpp()
{
int	internal_exist,external_exist;
int	external_68882;
#ifdef LUNA2
	if (machineid == LUNA_II) {
		return;
	}
#endif

    SET_INT_FPP;	/* internal = on, external = off */
    if ( internal_exist = havefpp() && is_68882() ) {	/* internal = 68882 */
	fpptype = FPP68882;
	return;
    } else {		/* internal don't exist  or it is not 68882 */
        SET_EXT_FPP;	/* internal = off, external = on */
	if ( internal_exist && 	/* internal = 68882, external <> 68882 */
	     (!(external_exist = havefpp()) || !(external_68882 = is_68882())) ) {
	   SET_INT_FPP;	/* internal = on, external = off */
	   fpptype = FPP68881;
	   return;
        }
	if ( internal_exist ) { /* internal = 68881, external = 68882 */
	   fpptype = FPP68882;
	   return;
        }
	if ( external_exist )  /* internal not exist, external exist */
	    if ( external_68882 ) { 	/* external = 68882 */
		fpptype = FPP68882;
		return;
	    } else { 			/* external = 68881 */
		fpptype = FPP68881;
		return;
	    }
	else		/* in/ex-ternal non exist */
	    panic("fpp non-existence");
    }
}
#endif
#endif