machdep.c

早期freebsd实现

/*
 * Copyright (c) 1988 University of Utah.
 * Copyright (c) 1992 OMRON Corporation.
 * Copyright (c) 1982, 1986, 1990, 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * from: Utah $Hdr: machdep.c 1.63 91/04/24$
 * from: hp300/hp300/machdep.c	8.3 (Berkeley) 11/14/93
 *
 *	@(#)machdep.c	8.3 (Berkeley) 1/12/94
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/signalvar.h>
#include <sys/kernel.h>
#include <sys/map.h>
#include <sys/proc.h>
#include <sys/buf.h>
#include <sys/reboot.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <sys/clist.h>
#include <sys/callout.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/msgbuf.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/mount.h>
#include <sys/user.h>
#include <sys/exec.h>
#include <sys/sysctl.h>
#ifdef SYSVSHM
#include <sys/shm.h>
#endif

#include <machine/cpu.h>
#include <machine/reg.h>
#include <machine/psl.h>
#include <luna68k/luna68k/cons.h>
#include <luna68k/luna68k/pte.h>
#include <net/netisr.h>

#define	MAXMEM	64*1024*CLSIZE	/* XXX - from cmap.h */
#include <vm/vm_kern.h>

/* the following is used externally (sysctl_hw) */
char machine[] = "luna68k";		/* cpu "architecture" */

vm_map_t buffer_map;
extern vm_offset_t avail_end;

/*
 * Declare these as initialized data so we can patch them.
 */
int	nswbuf = 0;
#ifdef	NBUF
int	nbuf = NBUF;
#else
int	nbuf = 0;
#endif
#ifdef	BUFPAGES
int	bufpages = BUFPAGES;
#else
int	bufpages = 0;
#endif
int	msgbufmapped;		/* set when safe to use msgbuf */
int	maxmem;			/* max memory per process */
int	physmem = MAXMEM;	/* max supported memory, changes to actual */
/*
 * safepri is a safe priority for sleep to set for a spin-wait
 * during autoconfiguration or after a panic.
 */
int	safepri = PSL_LOWIPL;

extern	u_int lowram;
extern	short exframesize[];

#ifdef FPCOPROC
int	fpptype = -1;
#endif

/*
 * Console initialization: called early on from main,
 * before vm init or startup.  Do enough configuration
 * to choose and initialize a console.
 */
consinit()
{

	/*
	 * Set cpuspeed immediately since cninit() called routines
	 * might use delay.
	 */

	cpuspeed = MHZ_25;

	/*
         * Find what hardware is attached to this machine.
         */
	find_devs();

	/*
	 * Initialize the console before we print anything out.
	 */
	cninit();
}

/*
 * cpu_startup: allocate memory for variable-sized tables,
 * initialize cpu, and do autoconfiguration.
 */
cpu_startup()
{
	register unsigned i;
	register caddr_t v, firstaddr;
	int base, residual;
	vm_offset_t minaddr, maxaddr;
	vm_size_t size;
#ifdef DEBUG
	extern int pmapdebug;
	int opmapdebug = pmapdebug;

	pmapdebug = 0;
#endif
	/*
	 * Initialize error message buffer (at end of core).
	 */
	for (i = 0; i < btoc(sizeof (struct msgbuf)); i++)
		pmap_enter(kernel_pmap, (vm_offset_t)msgbufp,
		    avail_end + i * NBPG, VM_PROT_ALL, TRUE);
	msgbufmapped = 1;

	/*
	 * Good {morning,afternoon,evening,night}.
	 */
	printf(version);
	identifyfpu();
	printf("real mem = %d\n", ctob(physmem));

	/*
	 * Allocate space for system data structures.
	 * The first available real memory address is in "firstaddr".
	 * The first available kernel virtual address is in "v".
	 * As pages of kernel virtual memory are allocated, "v" is incremented.
	 * As pages of memory are allocated and cleared,
	 * "firstaddr" is incremented.
	 * An index into the kernel page table corresponding to the
	 * virtual memory address maintained in "v" is kept in "mapaddr".
	 */
	/*
	 * Make two passes.  The first pass calculates how much memory is
	 * needed and allocates it.  The second pass assigns virtual
	 * addresses to the various data structures.
	 */
	firstaddr = 0;
again:
	v = (caddr_t)firstaddr;

#define	valloc(name, type, num) \
	    (name) = (type *)v; v = (caddr_t)((name)+(num))
#define	valloclim(name, type, num, lim) \
	    (name) = (type *)v; v = (caddr_t)((lim) = ((name)+(num)))
	valloc(cfree, struct cblock, nclist);
	valloc(callout, struct callout, ncallout);
	valloc(swapmap, struct map, nswapmap = maxproc * 2);
#ifdef SYSVSHM
	valloc(shmsegs, struct shmid_ds, shminfo.shmmni);
#endif
	
	/*
	 * Determine how many buffers to allocate.
	 * Since HPs tend to be long on memory and short on disk speed,
	 * we allocate more buffer space than the BSD standard of
	 * use 10% of memory for the first 2 Meg, 5% of remaining.
	 * We just allocate a flat 10%.  Insure a minimum of 16 buffers.
	 * We allocate 1/2 as many swap buffer headers as file i/o buffers.
	 */
	if (bufpages == 0)
		bufpages = physmem / 10 / CLSIZE;
	if (nbuf == 0) {
		nbuf = bufpages;
		if (nbuf < 16)
			nbuf = 16;
	}
	if (nswbuf == 0) {
		nswbuf = (nbuf / 2) &~ 1;	/* force even */
		if (nswbuf > 256)
			nswbuf = 256;		/* sanity */
	}
	valloc(swbuf, struct buf, nswbuf);
	valloc(buf, struct buf, nbuf);
	/*
	 * End of first pass, size has been calculated so allocate memory
	 */
	if (firstaddr == 0) {
		size = (vm_size_t)(v - firstaddr);
		firstaddr = (caddr_t) kmem_alloc(kernel_map, round_page(size));
		if (firstaddr == 0)
			panic("startup: no room for tables");
		goto again;
	}
	/*
	 * End of second pass, addresses have been assigned
	 */
	if ((vm_size_t)(v - firstaddr) != size)
		panic("startup: table size inconsistency");
	/*
	 * Now allocate buffers proper.  They are different than the above
	 * in that they usually occupy more virtual memory than physical.
	 */
	size = MAXBSIZE * nbuf;
	buffer_map = kmem_suballoc(kernel_map, (vm_offset_t *)&buffers,
				   &maxaddr, size, TRUE);
	minaddr = (vm_offset_t)buffers;
	if (vm_map_find(buffer_map, vm_object_allocate(size), (vm_offset_t)0,
			&minaddr, size, FALSE) != KERN_SUCCESS)
		panic("startup: cannot allocate buffers");
	base = bufpages / nbuf;
	residual = bufpages % nbuf;
	for (i = 0; i < nbuf; i++) {
		vm_size_t curbufsize;
		vm_offset_t curbuf;

		/*
		 * First <residual> buffers get (base+1) physical pages
		 * allocated for them.  The rest get (base) physical pages.
		 *
		 * The rest of each buffer occupies virtual space,
		 * but has no physical memory allocated for it.
		 */
		curbuf = (vm_offset_t)buffers + i * MAXBSIZE;
		curbufsize = CLBYTES * (i < residual ? base+1 : base);
		vm_map_pageable(buffer_map, curbuf, curbuf+curbufsize, FALSE);
		vm_map_simplify(buffer_map, curbuf);
	}
	/*
	 * Allocate a submap for exec arguments.  This map effectively
	 * limits the number of processes exec'ing at any time.
	 */
	exec_map = kmem_suballoc(kernel_map, &minaddr, &maxaddr,
				 16*NCARGS, TRUE);
	/*
	 * Allocate a submap for physio
	 */
	phys_map = kmem_suballoc(kernel_map, &minaddr, &maxaddr,
				 VM_PHYS_SIZE, TRUE);

	/*
	 * Finally, allocate mbuf pool.  Since mclrefcnt is an off-size
	 * we use the more space efficient malloc in place of kmem_alloc.
	 */
	mclrefcnt = (char *)malloc(NMBCLUSTERS+CLBYTES/MCLBYTES,
				   M_MBUF, M_NOWAIT);
	bzero(mclrefcnt, NMBCLUSTERS+CLBYTES/MCLBYTES);
	mb_map = kmem_suballoc(kernel_map, (vm_offset_t *)&mbutl, &maxaddr,
			       VM_MBUF_SIZE, FALSE);
	/*
	 * Initialize callouts
	 */
	callfree = callout;
	for (i = 1; i < ncallout; i++)
		callout[i-1].c_next = &callout[i];
	callout[i-1].c_next = NULL;

#ifdef DEBUG
	pmapdebug = opmapdebug;
#endif
	printf("avail mem = %d\n", ptoa(cnt.v_free_count));
	printf("using %d buffers containing %d bytes of memory\n",
		nbuf, bufpages * CLBYTES);
	/*
	 * Set up CPU-specific registers, cache, etc.
	 */
	initcpu();

	/*
	 * Set up buffers, so they can be used to read disk labels.
	 */
	bufinit();

	/*
	 * Configure the system.
	 */
	configure();
}

/*
 * Set registers on exec.
 * XXX Should clear registers except sp, pc,
 * but would break init; should be fixed soon.
 */
setregs(p, entry, retval)
	register struct proc *p;
	u_long entry;
	int retval[2];
{
	struct frame *frame = (struct frame *)p->p_md.md_regs;

	frame->f_pc = entry & ~1;
#ifdef FPCOPROC
	/* restore a null state frame */
	p->p_addr->u_pcb.pcb_fpregs.fpf_null = 0;
	m68881_restore(&p->p_addr->u_pcb.pcb_fpregs);
#endif
}

/*
 * Info for CTL_HW
 */
extern	char machine[];
char	cpu_model[120];
extern	char ostype[], osrelease[], version[];

identifyfpu()
{
#ifdef LUNA2
	if (machineid == LUNA_II) {
		sprintf(cpu_model, "LUNA-II (25MHz MC68040 CPU+MMU+FPU)");
		printf("%s\n", cpu_model);
		return;
	}
#endif
	if ( fpptype == -1 ) {
		printf("unknow FPU type \n");
		panic("startup");
	}
	sprintf(cpu_model, "LUNA-I (20MHz MC68030 CPU+MMU, 20MHz MC6888%d FPU)", fpptype);
	printf("%s\n", cpu_model);

/*
	printf("LUNA(20Mhz MC68030 CPU, 20Mhz MC6888%d FPU)\n",fpptype);
 */
}

#define SS_RTEFRAME	1
#define SS_FPSTATE	2
#define SS_USERREGS	4

struct sigstate {
	int	ss_flags;		/* which of the following are valid */
	struct	frame ss_frame;		/* original exception frame */
	struct	fpframe ss_fpstate;	/* 68881/68882 state info */
};

/*
 * WARNING: code in locore.s assumes the layout shown for sf_signum
 * thru sf_handler so... don't screw with them!
 */
struct sigframe {
	int	sf_signum;		/* signo for handler */
	int	sf_code;		/* additional info for handler */
	struct	sigcontext *sf_scp;	/* context ptr for handler */
	sig_t	sf_handler;		/* handler addr for u_sigc */
	struct	sigstate sf_state;	/* state of the hardware */
	struct	sigcontext sf_sc;	/* actual context */
};

#ifdef DEBUG
int sigdebug = 0;
int sigpid = 0;
#define SDB_FOLLOW	0x01
#define SDB_KSTACK	0x02
#define SDB_FPSTATE	0x04
#endif

/*
 * Send an interrupt to process.
 */
void
sendsig(catcher, sig, mask, code)
	sig_t catcher;
	int sig, mask;
	unsigned code;
{
	register struct proc *p = curproc;
	register struct sigframe *fp, *kfp;
	register struct frame *frame;
	register struct sigacts *psp = p->p_sigacts;
	register short ft;
	int oonstack, fsize;
	extern char sigcode[], esigcode[];

	frame = (struct frame *)p->p_md.md_regs;
	ft = frame->f_format;
	oonstack = psp->ps_sigstk.ss_flags & SA_ONSTACK;
	/*
	 * Allocate and validate space for the signal handler
	 * context. Note that if the stack is in P0 space, the
	 * call to grow() is a nop, and the useracc() check
	 * will fail if the process has not already allocated
	 * the space with a `brk'.
	 */
	fsize = sizeof(struct sigframe);
	if ((psp->ps_flags & SAS_ALTSTACK) &&
	    (psp->ps_sigstk.ss_flags & SA_ONSTACK) == 0 &&
	    (psp->ps_sigonstack & sigmask(sig))) {
		fp = (struct sigframe *)(psp->ps_sigstk.ss_base +
					 psp->ps_sigstk.ss_size - fsize);
		psp->ps_sigstk.ss_flags |= SA_ONSTACK;
	} else
		fp = (struct sigframe *)(frame->f_regs[SP] - fsize);
	if ((unsigned)fp <= USRSTACK - ctob(p->p_vmspace->vm_ssize)) 
		(void)grow(p, (unsigned)fp);
#ifdef DEBUG
	if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
		printf("sendsig(%d): sig %d ssp %x usp %x scp %x ft %d\n",
		       p->p_pid, sig, &oonstack, fp, &fp->sf_sc, ft);
#endif
	if (useracc((caddr_t)fp, fsize, B_WRITE) == 0) {
#ifdef DEBUG
		if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
			printf("sendsig(%d): useracc failed on sig %d\n",
			       p->p_pid, sig);
#endif
		/*
		 * Process has trashed its stack; give it an illegal
		 * instruction to halt it in its tracks.
		 */
		SIGACTION(p, SIGILL) = SIG_DFL;
		sig = sigmask(SIGILL);
		p->p_sigignore &= ~sig;
		p->p_sigcatch &= ~sig;
		p->p_sigmask &= ~sig;
		psignal(p, SIGILL);
		return;
	}
	kfp = (struct sigframe *)malloc((u_long)fsize, M_TEMP, M_WAITOK);
	/* 
	 * Build the argument list for the signal handler.
	 */
	kfp->sf_signum = sig;
	kfp->sf_code = code;
	kfp->sf_scp = &fp->sf_sc;
	kfp->sf_handler = catcher;
	/*
	 * Save necessary hardware state.  Currently this includes:
	 *	- general registers
	 *	- original exception frame (if not a "normal" frame)
	 *	- FP coprocessor state
	 */
	kfp->sf_state.ss_flags = SS_USERREGS;
	bcopy((caddr_t)frame->f_regs,
	      (caddr_t)kfp->sf_state.ss_frame.f_regs, sizeof frame->f_regs);
	if (ft >= FMT7) {
#ifdef DEBUG
		if (ft > 15 || exframesize[ft] < 0)
			panic("sendsig: bogus frame type");
#endif
		kfp->sf_state.ss_flags |= SS_RTEFRAME;
		kfp->sf_state.ss_frame.f_format = frame->f_format;
		kfp->sf_state.ss_frame.f_vector = frame->f_vector;
		bcopy((caddr_t)&frame->F_u,
		      (caddr_t)&kfp->sf_state.ss_frame.F_u, exframesize[ft]);
		/*
		 * Leave an indicator that we need to clean up the kernel
		 * stack.  We do this by setting the "pad word" above the
		 * hardware stack frame to the amount the stack must be
		 * adjusted by.
		 *
		 * N.B. we increment rather than just set f_stackadj in
		 * case we are called from syscall when processing a
		 * sigreturn.  In that case, f_stackadj may be non-zero.
		 */
		frame->f_stackadj += exframesize[ft];
		frame->f_format = frame->f_vector = 0;
#ifdef DEBUG
		if (sigdebug & SDB_FOLLOW)
			printf("sendsig(%d): copy out %d of frame %d\n",
			       p->p_pid, exframesize[ft], ft);
#endif
	}
#ifdef FPCOPROC
	kfp->sf_state.ss_flags |= SS_FPSTATE;
	m68881_save(&kfp->sf_state.ss_fpstate);
#ifdef DEBUG
	if ((sigdebug & SDB_FPSTATE) && *(char *)&kfp->sf_state.ss_fpstate)
		printf("sendsig(%d): copy out FP state (%x) to %x\n",
		       p->p_pid, *(u_int *)&kfp->sf_state.ss_fpstate,
		       &kfp->sf_state.ss_fpstate);
#endif
#endif
	/*
	 * Build the signal context to be used by sigreturn.
	 */
	kfp->sf_sc.sc_onstack = oonstack;
	kfp->sf_sc.sc_mask = mask;
	kfp->sf_sc.sc_sp = frame->f_regs[SP];
	kfp->sf_sc.sc_fp = frame->f_regs[A6];
	kfp->sf_sc.sc_ap = (int)&fp->sf_state;
	kfp->sf_sc.sc_pc = frame->f_pc;
	kfp->sf_sc.sc_ps = frame->f_sr;
	(void) copyout((caddr_t)kfp, (caddr_t)fp, fsize);
	frame->f_regs[SP] = (int)fp;
#ifdef DEBUG
	if (sigdebug & SDB_FOLLOW)
		printf("sendsig(%d): sig %d scp %x fp %x sc_sp %x sc_ap %x\n",
		       p->p_pid, sig, kfp->sf_scp, fp,
		       kfp->sf_sc.sc_sp, kfp->sf_sc.sc_ap);
#endif
	/*
	 * Signal trampoline code is at base of user stack.
	 */
	frame->f_pc = (int)PS_STRINGS - (esigcode - sigcode);
#ifdef DEBUG
	if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
		printf("sendsig(%d): sig %d returns\n",
		       p->p_pid, sig);
#endif
	free((caddr_t)kfp, M_TEMP);
}

/*
 * System call to cleanup state after a signal
 * has been taken.  Reset signal mask and
 * stack state from context left by sendsig (above).
 * Return to previous pc and psl as specified by
 * context left by sendsig. Check carefully to
 * make sure that the user has not modified the
 * psl to gain improper priviledges or to cause
 * a machine fault.
 */
struct sigreturn_args {
	struct sigcontext *sigcntxp;
};
/* ARGSUSED */
sigreturn(p, uap, retval)
	struct proc *p;
	struct sigreturn_args *uap;
	int *retval;
{
	register struct sigcontext *scp;
	register struct frame *frame;
	register int rf;
	struct sigcontext tsigc;
	struct sigstate tstate;
	int flags;

	scp = uap->sigcntxp;
#ifdef DEBUG
	if (sigdebug & SDB_FOLLOW)
		printf("sigreturn: pid %d, scp %x\n", p->p_pid, scp);
#endif
	if ((int)scp & 1)
		return (EINVAL);
	/*
	 * Test and fetch the context structure.
	 * We grab it all at once for speed.
	 */
	if (useracc((caddr_t)scp, sizeof (*scp), B_WRITE) == 0 ||
	    copyin((caddr_t)scp, (caddr_t)&tsigc, sizeof tsigc))
		return (EINVAL);
	scp = &tsigc;
	if ((scp->sc_ps & (PSL_MBZ|PSL_IPL|PSL_S)) != 0)
		return (EINVAL);
	/*
	 * Restore the user supplied information
	 */
	if (scp->sc_onstack & 01)
		p->p_sigacts->ps_sigstk.ss_flags |= SA_ONSTACK;
	else
		p->p_sigacts->ps_sigstk.ss_flags &= ~SA_ONSTACK;
	p->p_sigmask = scp->sc_mask &~ sigcantmask;
	frame = (struct frame *) p->p_md.md_regs;
	frame->f_regs[SP] = scp->sc_sp;
	frame->f_regs[A6] = scp->sc_fp;
	frame->f_pc = scp->sc_pc;
	frame->f_sr = scp->sc_ps;
	/*
	 * Grab pointer to hardware state information.
	 * If zero, the user is probably doing a longjmp.
	 */
	if ((rf = scp->sc_ap) == 0)
		return (EJUSTRETURN);
	/*
	 * See if there is anything to do before we go to the
	 * expense of copying in close to 1/2K of data
	 */
	flags = fuword((caddr_t)rf);
#ifdef DEBUG
	if (sigdebug & SDB_FOLLOW)
		printf("sigreturn(%d): sc_ap %x flags %x\n",
		       p->p_pid, rf, flags);
#endif