+/*-
+ * Copyright (c) 1990 William Jolitz.
+ * Copyright (c) 1991 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * 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.
+ *
+ * @(#)npx.c 7.2 (Berkeley) 5/12/91
+ */
+static char rcsid[] = "$Header: /usr/bill/working/sys/i386/isa/RCS/npx.c,v 1.2 92/01/21 14:34:27 william Exp $";
+#include "npx.h"
+#if NNPX > 0
+
+#include "param.h"
+#include "systm.h"
+#include "conf.h"
+#include "file.h"
+#include "proc.h"
+#include "machine/cpu.h"
+#include "machine/pcb.h"
+#include "machine/trap.h"
+#include "ioctl.h"
+#include "machine/specialreg.h"
+#include "i386/isa/isa_device.h"
+#include "icu.h"
+/*
+ * 387 and 287 Numeric Coprocessor Extension (NPX) Driver.
+ */
+
+int npxprobe(), npxattach(), npxintr();
+struct isa_driver npxdriver = {
+ npxprobe, npxattach, "npx",
+};
+
+struct proc *npxproc; /* process who owns device, otherwise zero */
+struct pcb *npxpcb; /* owners context structure */
+int npxexists;
+extern long npx0mask;
+
+/*
+ * Probe routine - look device, otherwise set emulator bit
+ */
+npxprobe(dvp)
+ struct isa_device *dvp;
+{ static status, control;
+
+#ifdef lint
+ npxintr();
+#endif
+
+ /* insure EM bit off */
+ load_cr0(rcr0() & ~CR0_EM); /* stop emulating */
+ asm(" fninit "); /* put device in known state */
+
+ /* check for a proper status of zero */
+ status = 0x5a5a;
+ asm (" fnstsw %0 " : "=m" (status) : "m" (status) );
+
+ if ((status&0xff) == 0) {
+
+ /* good, now check for a proper control word */
+ asm (" fnstcw %0 " : "=m" (status) : "m" (status));
+
+ if ((status&0x103f) == 0x3f) {
+ /* then we have a numeric coprocessor */
+ /* XXX should force an exception here to generate an intr */
+ return (1);
+ }
+ }
+
+ /* insure EM bit on */
+ load_cr0(rcr0() | CR0_EM); /* start emulating */
+ return (0);
+}
+
+/*
+ * Attach routine - announce which it is, and wire into system
+ */
+npxattach(dvp)
+ struct isa_device *dvp;
+{
+
+ npxinit(__INITIAL_NPXCW__);
+ npxexists++;
+ npx0mask = dvp->id_irq;
+}
+
+/*
+ * Initialize floating point unit.
+ */
+npxinit(control) {
+ static short wd;
+
+ if (npxexists == 0) return;
+
+
+ wd = control;
+ wd = 0x272;
+ load_cr0(rcr0() & ~CR0_EM); /* stop emulating */
+ asm (" fninit");
+ asm(" fldcw %0" : : "g" (wd));
+ if (curpcb) {
+ asm(" fnsave %0 " : : "g" (curpcb->pcb_savefpu) );
+ curpcb->pcb_flags |= FP_NEEDSRESTORE;
+ }
+ load_cr0(rcr0() | CR0_EM); /* start emulating */
+ outb(0xb1,0); /* reset processor */
+}
+
+/*
+ * Load floating point context and record ownership to suite
+ */
+npxload() {
+
+ if (npxproc) panic ("npxload");
+ npxproc = curproc;
+ npxpcb = curpcb;
+ asm(" frstor %0 " : : "g" (curpcb->pcb_savefpu) );
+}
+
+/*
+ * Unload floating point context and relinquish ownership
+ */
+npxunload() {
+
+ if (npxproc == 0) panic ("npxunload");
+ asm(" fsave %0 " : : "g" (npxpcb->pcb_savefpu) );
+ npxproc = 0 ;
+}
+
+/*
+ * Record information needed in processing an exception and clear status word
+ */
+npxintr(frame) struct intrframe frame; {
+ int code;
+static status;
+
+ outb(0xf0,0); /* reset processor */
+/*pg("npxintr");*/
+
+ asm (" fnstsw %0 " : "=m" (status) : "m" (status) );
+ /* sync state in process context structure, in advance of debugger/process looking for it */
+ if (npxproc == 0 || npxexists == 0) panic ("npxintr");
+ asm (" fnsave %0 " : : "g" (npxpcb->pcb_savefpu) );
+
+#ifdef notyet
+ /* encode the appropriate code for detailed information on this exception */
+ code = ???;
+#else
+ code = 0; /* XXX */
+#endif
+
+/*if((pg("status %x", status) & 0x7f) == 't') {*/
+ /* pass exception to process, which may not be the current one */
+ if (npxproc == curproc) {
+ /* Q: what if in an interrupt, or in trap processing? */
+ if (ISPL(frame.if_cs) == SEL_UPL) {
+ curproc->p_regs = (int *)&frame.if_es;
+ curpcb->pcb_flags |= FM_TRAP; /* used by sendsig */
+ } /* else printf("*");*/
+ trapsignal(curproc, SIGFPE, code);
+ curpcb->pcb_flags &= ~FM_TRAP; /* used by sendsig */
+ } else {
+ /* printf("P");*/
+ psignal(npxproc, SIGFPE);
+ }
+/*}*/
+
+ /* clear the exception so we can catch others like it */
+ asm (" fnclex");
+}
+
+/*
+ * Implement device not available (DNA) exception
+ */
+npxdna() {
+/*pg("npxdna");*/
+
+
+ if (npxexists == 0) return(0);
+ load_cr0(rcr0() & ~CR0_EM); /* stop emulating */
+ if (curpcb->pcb_flags & FP_NEEDSRESTORE)
+ asm(" frstor %0 " : : "g" (curpcb->pcb_savefpu));
+ curpcb->pcb_flags |= FP_WASUSED | FP_NEEDSSAVE;
+ curpcb->pcb_flags &= ~FP_NEEDSRESTORE;
+ npxproc = curproc;
+ npxpcb = curpcb;
+ return (1);
+}
+#endif
projects / unix-history / commitdiff