1c1771cb5b
simpler for npx exceptions that start as traps (no assembly required...) and works better for npx exceptions that start as interrupts (there is no longer a problem for nested interrupts). Submitted by: original (pre-SMPng) version by luoqi
987 lines
30 KiB
C
987 lines
30 KiB
C
/*-
|
|
* 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.
|
|
*
|
|
* from: @(#)npx.c 7.2 (Berkeley) 5/12/91
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include "opt_debug_npx.h"
|
|
#include "opt_math_emulate.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/bus.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/module.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/sysctl.h>
|
|
#include <machine/bus.h>
|
|
#include <sys/rman.h>
|
|
#ifdef NPX_DEBUG
|
|
#include <sys/syslog.h>
|
|
#endif
|
|
#include <sys/signalvar.h>
|
|
#include <sys/user.h>
|
|
|
|
#ifndef SMP
|
|
#include <machine/asmacros.h>
|
|
#endif
|
|
#include <machine/cputypes.h>
|
|
#include <machine/frame.h>
|
|
#include <machine/md_var.h>
|
|
#include <machine/pcb.h>
|
|
#include <machine/psl.h>
|
|
#ifndef SMP
|
|
#include <machine/clock.h>
|
|
#endif
|
|
#include <machine/resource.h>
|
|
#include <machine/specialreg.h>
|
|
#include <machine/segments.h>
|
|
|
|
#ifndef SMP
|
|
#include <i386/isa/icu.h>
|
|
#include <i386/isa/intr_machdep.h>
|
|
#include <i386/isa/isa.h>
|
|
#endif
|
|
#include <isa/isavar.h>
|
|
|
|
/*
|
|
* 387 and 287 Numeric Coprocessor Extension (NPX) Driver.
|
|
*/
|
|
|
|
/* Configuration flags. */
|
|
#define NPX_DISABLE_I586_OPTIMIZED_BCOPY (1 << 0)
|
|
#define NPX_DISABLE_I586_OPTIMIZED_BZERO (1 << 1)
|
|
#define NPX_DISABLE_I586_OPTIMIZED_COPYIO (1 << 2)
|
|
#define NPX_PREFER_EMULATOR (1 << 3)
|
|
|
|
#ifdef __GNUC__
|
|
|
|
#define fldcw(addr) __asm("fldcw %0" : : "m" (*(addr)))
|
|
#define fnclex() __asm("fnclex")
|
|
#define fninit() __asm("fninit")
|
|
#define fnsave(addr) __asm __volatile("fnsave %0" : "=m" (*(addr)))
|
|
#define fnstcw(addr) __asm __volatile("fnstcw %0" : "=m" (*(addr)))
|
|
#define fnstsw(addr) __asm __volatile("fnstsw %0" : "=m" (*(addr)))
|
|
#define fp_divide_by_0() __asm("fldz; fld1; fdiv %st,%st(1); fnop")
|
|
#define frstor(addr) __asm("frstor %0" : : "m" (*(addr)))
|
|
#define start_emulating() __asm("smsw %%ax; orb %0,%%al; lmsw %%ax" \
|
|
: : "n" (CR0_TS) : "ax")
|
|
#define stop_emulating() __asm("clts")
|
|
|
|
#else /* not __GNUC__ */
|
|
|
|
void fldcw __P((caddr_t addr));
|
|
void fnclex __P((void));
|
|
void fninit __P((void));
|
|
void fnsave __P((caddr_t addr));
|
|
void fnstcw __P((caddr_t addr));
|
|
void fnstsw __P((caddr_t addr));
|
|
void fp_divide_by_0 __P((void));
|
|
void frstor __P((caddr_t addr));
|
|
void start_emulating __P((void));
|
|
void stop_emulating __P((void));
|
|
|
|
#endif /* __GNUC__ */
|
|
|
|
typedef u_char bool_t;
|
|
|
|
static int npx_attach __P((device_t dev));
|
|
static void npx_identify __P((driver_t *driver, device_t parent));
|
|
#ifndef SMP
|
|
static void npx_intr __P((void *));
|
|
#endif
|
|
static int npx_probe __P((device_t dev));
|
|
static int npx_probe1 __P((device_t dev));
|
|
#ifdef I586_CPU
|
|
static long timezero __P((const char *funcname,
|
|
void (*func)(void *buf, size_t len)));
|
|
#endif /* I586_CPU */
|
|
|
|
int hw_float; /* XXX currently just alias for npx_exists */
|
|
|
|
SYSCTL_INT(_hw,HW_FLOATINGPT, floatingpoint,
|
|
CTLFLAG_RD, &hw_float, 0,
|
|
"Floatingpoint instructions executed in hardware");
|
|
|
|
#ifndef SMP
|
|
static volatile u_int npx_intrs_while_probing;
|
|
static volatile u_int npx_traps_while_probing;
|
|
#endif
|
|
|
|
static bool_t npx_ex16;
|
|
static bool_t npx_exists;
|
|
static bool_t npx_irq13;
|
|
static int npx_irq; /* irq number */
|
|
|
|
#ifndef SMP
|
|
/*
|
|
* Special interrupt handlers. Someday intr0-intr15 will be used to count
|
|
* interrupts. We'll still need a special exception 16 handler. The busy
|
|
* latch stuff in probeintr() can be moved to npxprobe().
|
|
*/
|
|
inthand_t probeintr;
|
|
__asm(" \n\
|
|
.text \n\
|
|
.p2align 2,0x90 \n\
|
|
.type " __XSTRING(CNAME(probeintr)) ",@function \n\
|
|
" __XSTRING(CNAME(probeintr)) ": \n\
|
|
ss \n\
|
|
incl " __XSTRING(CNAME(npx_intrs_while_probing)) " \n\
|
|
pushl %eax \n\
|
|
movb $0x20,%al # EOI (asm in strings loses cpp features) \n\
|
|
outb %al,$0xa0 # IO_ICU2 \n\
|
|
outb %al,$0x20 # IO_ICU1 \n\
|
|
movb $0,%al \n\
|
|
outb %al,$0xf0 # clear BUSY# latch \n\
|
|
popl %eax \n\
|
|
iret \n\
|
|
");
|
|
|
|
inthand_t probetrap;
|
|
__asm(" \n\
|
|
.text \n\
|
|
.p2align 2,0x90 \n\
|
|
.type " __XSTRING(CNAME(probetrap)) ",@function \n\
|
|
" __XSTRING(CNAME(probetrap)) ": \n\
|
|
ss \n\
|
|
incl " __XSTRING(CNAME(npx_traps_while_probing)) " \n\
|
|
fnclex \n\
|
|
iret \n\
|
|
");
|
|
#endif /* SMP */
|
|
|
|
/*
|
|
* Identify routine. Create a connection point on our parent for probing.
|
|
*/
|
|
static void
|
|
npx_identify(driver, parent)
|
|
driver_t *driver;
|
|
device_t parent;
|
|
{
|
|
device_t child;
|
|
|
|
child = BUS_ADD_CHILD(parent, 0, "npx", 0);
|
|
if (child == NULL)
|
|
panic("npx_identify");
|
|
}
|
|
|
|
#ifndef SMP
|
|
/*
|
|
* Do minimal handling of npx interrupts to convert them to traps.
|
|
*/
|
|
static void
|
|
npx_intr(dummy)
|
|
void *dummy;
|
|
{
|
|
struct proc *p;
|
|
|
|
/*
|
|
* The BUSY# latch must be cleared in all cases so that the next
|
|
* unmasked npx exception causes an interrupt.
|
|
*/
|
|
outb(0xf0, 0);
|
|
|
|
/*
|
|
* npxproc is normally non-null here. In that case, schedule an
|
|
* AST to finish the exception handling in the correct context
|
|
* (this interrupt may occur after the process has entered the
|
|
* kernel via a syscall or an interrupt). Otherwise, the npx
|
|
* state of the process that caused this interrupt must have been
|
|
* pushed to the process' pcb, and clearing of the busy latch
|
|
* above has finished the (essentially null) handling of this
|
|
* interrupt. Control will eventually return to the instruction
|
|
* that caused it and it will repeat. We will eventually (usually
|
|
* soon) win the race to handle the interrupt properly.
|
|
*/
|
|
p = PCPU_GET(npxproc);
|
|
if (p != NULL) {
|
|
p->p_addr->u_pcb.pcb_flags |= PCB_NPXTRAP;
|
|
mtx_lock_spin(&sched_lock);
|
|
aston(p);
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* XXX these "local" variables of npx_probe() are non-local so that
|
|
* npxprobe1() can abuse them.
|
|
*/
|
|
static int npx_intrno;
|
|
static struct gate_descriptor save_idt_npxintr;
|
|
#endif /* !SMP */
|
|
|
|
/*
|
|
* Probe routine. Initialize cr0 to give correct behaviour for [f]wait
|
|
* whether the device exists or not (XXX should be elsewhere). Set flags
|
|
* to tell npxattach() what to do. Modify device struct if npx doesn't
|
|
* need to use interrupts. Return 1 if device exists.
|
|
*/
|
|
static int
|
|
npx_probe(dev)
|
|
device_t dev;
|
|
{
|
|
#ifdef SMP
|
|
|
|
if (resource_int_value("npx", 0, "irq", &npx_irq) != 0)
|
|
npx_irq = 13;
|
|
return npx_probe1(dev);
|
|
|
|
#else /* SMP */
|
|
|
|
int result;
|
|
critical_t savecrit;
|
|
u_char save_icu1_mask;
|
|
u_char save_icu2_mask;
|
|
struct gate_descriptor save_idt_npxtrap;
|
|
/*
|
|
* This routine is now just a wrapper for npxprobe1(), to install
|
|
* special npx interrupt and trap handlers, to enable npx interrupts
|
|
* and to disable other interrupts. Someday isa_configure() will
|
|
* install suitable handlers and run with interrupts enabled so we
|
|
* won't need to do so much here.
|
|
*/
|
|
if (resource_int_value("npx", 0, "irq", &npx_irq) != 0)
|
|
npx_irq = 13;
|
|
npx_intrno = NRSVIDT + npx_irq;
|
|
savecrit = critical_enter();
|
|
save_icu1_mask = inb(IO_ICU1 + 1);
|
|
save_icu2_mask = inb(IO_ICU2 + 1);
|
|
save_idt_npxintr = idt[npx_intrno];
|
|
save_idt_npxtrap = idt[16];
|
|
outb(IO_ICU1 + 1, ~IRQ_SLAVE);
|
|
outb(IO_ICU2 + 1, ~(1 << (npx_irq - 8)));
|
|
setidt(16, probetrap, SDT_SYS386TGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
|
|
setidt(npx_intrno, probeintr, SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
|
|
|
|
/*
|
|
* XXX This looks highly bogus, but it appears that npc_probe1
|
|
* needs interrupts enabled. Does this make any difference
|
|
* here?
|
|
*/
|
|
critical_exit(savecrit);
|
|
result = npx_probe1(dev);
|
|
savecrit = critical_enter();
|
|
outb(IO_ICU1 + 1, save_icu1_mask);
|
|
outb(IO_ICU2 + 1, save_icu2_mask);
|
|
idt[npx_intrno] = save_idt_npxintr;
|
|
idt[16] = save_idt_npxtrap;
|
|
critical_exit(savecrit);
|
|
return (result);
|
|
|
|
#endif /* SMP */
|
|
}
|
|
|
|
static int
|
|
npx_probe1(dev)
|
|
device_t dev;
|
|
{
|
|
#ifndef SMP
|
|
u_short control;
|
|
u_short status;
|
|
#endif
|
|
|
|
/*
|
|
* Partially reset the coprocessor, if any. Some BIOS's don't reset
|
|
* it after a warm boot.
|
|
*/
|
|
outb(0xf1, 0); /* full reset on some systems, NOP on others */
|
|
outb(0xf0, 0); /* clear BUSY# latch */
|
|
/*
|
|
* Prepare to trap all ESC (i.e., NPX) instructions and all WAIT
|
|
* instructions. We must set the CR0_MP bit and use the CR0_TS
|
|
* bit to control the trap, because setting the CR0_EM bit does
|
|
* not cause WAIT instructions to trap. It's important to trap
|
|
* WAIT instructions - otherwise the "wait" variants of no-wait
|
|
* control instructions would degenerate to the "no-wait" variants
|
|
* after FP context switches but work correctly otherwise. It's
|
|
* particularly important to trap WAITs when there is no NPX -
|
|
* otherwise the "wait" variants would always degenerate.
|
|
*
|
|
* Try setting CR0_NE to get correct error reporting on 486DX's.
|
|
* Setting it should fail or do nothing on lesser processors.
|
|
*/
|
|
load_cr0(rcr0() | CR0_MP | CR0_NE);
|
|
/*
|
|
* But don't trap while we're probing.
|
|
*/
|
|
stop_emulating();
|
|
/*
|
|
* Finish resetting the coprocessor, if any. If there is an error
|
|
* pending, then we may get a bogus IRQ13, but probeintr() will handle
|
|
* it OK. Bogus halts have never been observed, but we enabled
|
|
* IRQ13 and cleared the BUSY# latch early to handle them anyway.
|
|
*/
|
|
fninit();
|
|
|
|
#ifdef SMP
|
|
/*
|
|
* Exception 16 MUST work for SMP.
|
|
*/
|
|
npx_irq13 = 0;
|
|
npx_ex16 = hw_float = npx_exists = 1;
|
|
device_set_desc(dev, "math processor");
|
|
return (0);
|
|
|
|
#else /* !SMP */
|
|
device_set_desc(dev, "math processor");
|
|
|
|
/*
|
|
* Don't use fwait here because it might hang.
|
|
* Don't use fnop here because it usually hangs if there is no FPU.
|
|
*/
|
|
DELAY(1000); /* wait for any IRQ13 */
|
|
#ifdef DIAGNOSTIC
|
|
if (npx_intrs_while_probing != 0)
|
|
printf("fninit caused %u bogus npx interrupt(s)\n",
|
|
npx_intrs_while_probing);
|
|
if (npx_traps_while_probing != 0)
|
|
printf("fninit caused %u bogus npx trap(s)\n",
|
|
npx_traps_while_probing);
|
|
#endif
|
|
/*
|
|
* Check for a status of mostly zero.
|
|
*/
|
|
status = 0x5a5a;
|
|
fnstsw(&status);
|
|
if ((status & 0xb8ff) == 0) {
|
|
/*
|
|
* Good, now check for a proper control word.
|
|
*/
|
|
control = 0x5a5a;
|
|
fnstcw(&control);
|
|
if ((control & 0x1f3f) == 0x033f) {
|
|
hw_float = npx_exists = 1;
|
|
/*
|
|
* We have an npx, now divide by 0 to see if exception
|
|
* 16 works.
|
|
*/
|
|
control &= ~(1 << 2); /* enable divide by 0 trap */
|
|
fldcw(&control);
|
|
npx_traps_while_probing = npx_intrs_while_probing = 0;
|
|
fp_divide_by_0();
|
|
if (npx_traps_while_probing != 0) {
|
|
/*
|
|
* Good, exception 16 works.
|
|
*/
|
|
npx_ex16 = 1;
|
|
return (0);
|
|
}
|
|
if (npx_intrs_while_probing != 0) {
|
|
int rid;
|
|
struct resource *r;
|
|
void *intr;
|
|
/*
|
|
* Bad, we are stuck with IRQ13.
|
|
*/
|
|
npx_irq13 = 1;
|
|
|
|
/*
|
|
* We allocate these resources permanently,
|
|
* so there is no need to keep track of them.
|
|
*/
|
|
rid = 0;
|
|
r = bus_alloc_resource(dev, SYS_RES_IOPORT,
|
|
&rid, IO_NPX, IO_NPX,
|
|
IO_NPXSIZE, RF_ACTIVE);
|
|
if (r == 0)
|
|
panic("npx: can't get ports");
|
|
rid = 0;
|
|
r = bus_alloc_resource(dev, SYS_RES_IRQ,
|
|
&rid, npx_irq, npx_irq,
|
|
1, RF_ACTIVE);
|
|
if (r == 0)
|
|
panic("npx: can't get IRQ");
|
|
BUS_SETUP_INTR(device_get_parent(dev),
|
|
dev, r,
|
|
INTR_TYPE_MISC | INTR_FAST,
|
|
npx_intr, 0, &intr);
|
|
if (intr == 0)
|
|
panic("npx: can't create intr");
|
|
|
|
/*
|
|
* XXX BUS_SETUP_INTR() has changed
|
|
* idt[npx_intrno] to point to Xfastintr0
|
|
* instead of Xfastintr0. Adjust
|
|
* save_idt_npxintr so that npxprobe()
|
|
* doesn't undo this.
|
|
*/
|
|
save_idt_npxintr = idt[npx_intrno];
|
|
|
|
return (0);
|
|
}
|
|
/*
|
|
* Worse, even IRQ13 is broken. Use emulator.
|
|
*/
|
|
}
|
|
}
|
|
/*
|
|
* Probe failed, but we want to get to npxattach to initialize the
|
|
* emulator and say that it has been installed. XXX handle devices
|
|
* that aren't really devices better.
|
|
*/
|
|
return (0);
|
|
#endif /* SMP */
|
|
}
|
|
|
|
/*
|
|
* Attach routine - announce which it is, and wire into system
|
|
*/
|
|
int
|
|
npx_attach(dev)
|
|
device_t dev;
|
|
{
|
|
int flags;
|
|
|
|
if (resource_int_value("npx", 0, "flags", &flags) != 0)
|
|
flags = 0;
|
|
|
|
if (flags)
|
|
device_printf(dev, "flags 0x%x ", flags);
|
|
if (npx_irq13) {
|
|
device_printf(dev, "using IRQ 13 interface\n");
|
|
} else {
|
|
#if defined(MATH_EMULATE) || defined(GPL_MATH_EMULATE)
|
|
if (npx_ex16) {
|
|
if (!(flags & NPX_PREFER_EMULATOR))
|
|
device_printf(dev, "INT 16 interface\n");
|
|
else {
|
|
device_printf(dev, "FPU exists, but flags request "
|
|
"emulator\n");
|
|
hw_float = npx_exists = 0;
|
|
}
|
|
} else if (npx_exists) {
|
|
device_printf(dev, "error reporting broken; using 387 emulator\n");
|
|
hw_float = npx_exists = 0;
|
|
} else
|
|
device_printf(dev, "387 emulator\n");
|
|
#else
|
|
if (npx_ex16) {
|
|
device_printf(dev, "INT 16 interface\n");
|
|
if (flags & NPX_PREFER_EMULATOR) {
|
|
device_printf(dev, "emulator requested, but none compiled "
|
|
"into kernel, using FPU\n");
|
|
}
|
|
} else
|
|
device_printf(dev, "no 387 emulator in kernel and no FPU!\n");
|
|
#endif
|
|
}
|
|
npxinit(__INITIAL_NPXCW__);
|
|
|
|
#ifdef I586_CPU_XXX
|
|
if (cpu_class == CPUCLASS_586 && npx_ex16 && npx_exists &&
|
|
timezero("i586_bzero()", i586_bzero) <
|
|
timezero("bzero()", bzero) * 4 / 5) {
|
|
if (!(flags & NPX_DISABLE_I586_OPTIMIZED_BCOPY)) {
|
|
bcopy_vector = i586_bcopy;
|
|
ovbcopy_vector = i586_bcopy;
|
|
}
|
|
if (!(flags & NPX_DISABLE_I586_OPTIMIZED_BZERO))
|
|
bzero = i586_bzero;
|
|
if (!(flags & NPX_DISABLE_I586_OPTIMIZED_COPYIO)) {
|
|
copyin_vector = i586_copyin;
|
|
copyout_vector = i586_copyout;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
return (0); /* XXX unused */
|
|
}
|
|
|
|
/*
|
|
* Initialize floating point unit.
|
|
*/
|
|
void
|
|
npxinit(control)
|
|
u_short control;
|
|
{
|
|
struct save87 dummy;
|
|
critical_t savecrit;
|
|
|
|
if (!npx_exists)
|
|
return;
|
|
/*
|
|
* fninit has the same h/w bugs as fnsave. Use the detoxified
|
|
* fnsave to throw away any junk in the fpu. npxsave() initializes
|
|
* the fpu and sets npxproc = NULL as important side effects.
|
|
*/
|
|
savecrit = critical_enter();
|
|
npxsave(&dummy);
|
|
stop_emulating();
|
|
fldcw(&control);
|
|
if (PCPU_GET(curpcb) != NULL)
|
|
fnsave(&PCPU_GET(curpcb)->pcb_savefpu);
|
|
start_emulating();
|
|
critical_exit(savecrit);
|
|
}
|
|
|
|
/*
|
|
* Free coprocessor (if we have it).
|
|
*/
|
|
void
|
|
npxexit(p)
|
|
struct proc *p;
|
|
{
|
|
critical_t savecrit;
|
|
|
|
savecrit = critical_enter();
|
|
if (p == PCPU_GET(npxproc))
|
|
npxsave(&PCPU_GET(curpcb)->pcb_savefpu);
|
|
critical_exit(savecrit);
|
|
#ifdef NPX_DEBUG
|
|
if (npx_exists) {
|
|
u_int masked_exceptions;
|
|
|
|
masked_exceptions = PCPU_GET(curpcb)->pcb_savefpu.sv_env.en_cw
|
|
& PCPU_GET(curpcb)->pcb_savefpu.sv_env.en_sw & 0x7f;
|
|
/*
|
|
* Log exceptions that would have trapped with the old
|
|
* control word (overflow, divide by 0, and invalid operand).
|
|
*/
|
|
if (masked_exceptions & 0x0d)
|
|
log(LOG_ERR,
|
|
"pid %d (%s) exited with masked floating point exceptions 0x%02x\n",
|
|
p->p_pid, p->p_comm, masked_exceptions);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* The following mechanism is used to ensure that the FPE_... value
|
|
* that is passed as a trapcode to the signal handler of the user
|
|
* process does not have more than one bit set.
|
|
*
|
|
* Multiple bits may be set if the user process modifies the control
|
|
* word while a status word bit is already set. While this is a sign
|
|
* of bad coding, we have no choise than to narrow them down to one
|
|
* bit, since we must not send a trapcode that is not exactly one of
|
|
* the FPE_ macros.
|
|
*
|
|
* The mechanism has a static table with 127 entries. Each combination
|
|
* of the 7 FPU status word exception bits directly translates to a
|
|
* position in this table, where a single FPE_... value is stored.
|
|
* This FPE_... value stored there is considered the "most important"
|
|
* of the exception bits and will be sent as the signal code. The
|
|
* precedence of the bits is based upon Intel Document "Numerical
|
|
* Applications", Chapter "Special Computational Situations".
|
|
*
|
|
* The macro to choose one of these values does these steps: 1) Throw
|
|
* away status word bits that cannot be masked. 2) Throw away the bits
|
|
* currently masked in the control word, assuming the user isn't
|
|
* interested in them anymore. 3) Reinsert status word bit 7 (stack
|
|
* fault) if it is set, which cannot be masked but must be presered.
|
|
* 4) Use the remaining bits to point into the trapcode table.
|
|
*
|
|
* The 6 maskable bits in order of their preference, as stated in the
|
|
* above referenced Intel manual:
|
|
* 1 Invalid operation (FP_X_INV)
|
|
* 1a Stack underflow
|
|
* 1b Stack overflow
|
|
* 1c Operand of unsupported format
|
|
* 1d SNaN operand.
|
|
* 2 QNaN operand (not an exception, irrelavant here)
|
|
* 3 Any other invalid-operation not mentioned above or zero divide
|
|
* (FP_X_INV, FP_X_DZ)
|
|
* 4 Denormal operand (FP_X_DNML)
|
|
* 5 Numeric over/underflow (FP_X_OFL, FP_X_UFL)
|
|
* 6 Inexact result (FP_X_IMP)
|
|
*/
|
|
static char fpetable[128] = {
|
|
0,
|
|
FPE_FLTINV, /* 1 - INV */
|
|
FPE_FLTUND, /* 2 - DNML */
|
|
FPE_FLTINV, /* 3 - INV | DNML */
|
|
FPE_FLTDIV, /* 4 - DZ */
|
|
FPE_FLTINV, /* 5 - INV | DZ */
|
|
FPE_FLTDIV, /* 6 - DNML | DZ */
|
|
FPE_FLTINV, /* 7 - INV | DNML | DZ */
|
|
FPE_FLTOVF, /* 8 - OFL */
|
|
FPE_FLTINV, /* 9 - INV | OFL */
|
|
FPE_FLTUND, /* A - DNML | OFL */
|
|
FPE_FLTINV, /* B - INV | DNML | OFL */
|
|
FPE_FLTDIV, /* C - DZ | OFL */
|
|
FPE_FLTINV, /* D - INV | DZ | OFL */
|
|
FPE_FLTDIV, /* E - DNML | DZ | OFL */
|
|
FPE_FLTINV, /* F - INV | DNML | DZ | OFL */
|
|
FPE_FLTUND, /* 10 - UFL */
|
|
FPE_FLTINV, /* 11 - INV | UFL */
|
|
FPE_FLTUND, /* 12 - DNML | UFL */
|
|
FPE_FLTINV, /* 13 - INV | DNML | UFL */
|
|
FPE_FLTDIV, /* 14 - DZ | UFL */
|
|
FPE_FLTINV, /* 15 - INV | DZ | UFL */
|
|
FPE_FLTDIV, /* 16 - DNML | DZ | UFL */
|
|
FPE_FLTINV, /* 17 - INV | DNML | DZ | UFL */
|
|
FPE_FLTOVF, /* 18 - OFL | UFL */
|
|
FPE_FLTINV, /* 19 - INV | OFL | UFL */
|
|
FPE_FLTUND, /* 1A - DNML | OFL | UFL */
|
|
FPE_FLTINV, /* 1B - INV | DNML | OFL | UFL */
|
|
FPE_FLTDIV, /* 1C - DZ | OFL | UFL */
|
|
FPE_FLTINV, /* 1D - INV | DZ | OFL | UFL */
|
|
FPE_FLTDIV, /* 1E - DNML | DZ | OFL | UFL */
|
|
FPE_FLTINV, /* 1F - INV | DNML | DZ | OFL | UFL */
|
|
FPE_FLTRES, /* 20 - IMP */
|
|
FPE_FLTINV, /* 21 - INV | IMP */
|
|
FPE_FLTUND, /* 22 - DNML | IMP */
|
|
FPE_FLTINV, /* 23 - INV | DNML | IMP */
|
|
FPE_FLTDIV, /* 24 - DZ | IMP */
|
|
FPE_FLTINV, /* 25 - INV | DZ | IMP */
|
|
FPE_FLTDIV, /* 26 - DNML | DZ | IMP */
|
|
FPE_FLTINV, /* 27 - INV | DNML | DZ | IMP */
|
|
FPE_FLTOVF, /* 28 - OFL | IMP */
|
|
FPE_FLTINV, /* 29 - INV | OFL | IMP */
|
|
FPE_FLTUND, /* 2A - DNML | OFL | IMP */
|
|
FPE_FLTINV, /* 2B - INV | DNML | OFL | IMP */
|
|
FPE_FLTDIV, /* 2C - DZ | OFL | IMP */
|
|
FPE_FLTINV, /* 2D - INV | DZ | OFL | IMP */
|
|
FPE_FLTDIV, /* 2E - DNML | DZ | OFL | IMP */
|
|
FPE_FLTINV, /* 2F - INV | DNML | DZ | OFL | IMP */
|
|
FPE_FLTUND, /* 30 - UFL | IMP */
|
|
FPE_FLTINV, /* 31 - INV | UFL | IMP */
|
|
FPE_FLTUND, /* 32 - DNML | UFL | IMP */
|
|
FPE_FLTINV, /* 33 - INV | DNML | UFL | IMP */
|
|
FPE_FLTDIV, /* 34 - DZ | UFL | IMP */
|
|
FPE_FLTINV, /* 35 - INV | DZ | UFL | IMP */
|
|
FPE_FLTDIV, /* 36 - DNML | DZ | UFL | IMP */
|
|
FPE_FLTINV, /* 37 - INV | DNML | DZ | UFL | IMP */
|
|
FPE_FLTOVF, /* 38 - OFL | UFL | IMP */
|
|
FPE_FLTINV, /* 39 - INV | OFL | UFL | IMP */
|
|
FPE_FLTUND, /* 3A - DNML | OFL | UFL | IMP */
|
|
FPE_FLTINV, /* 3B - INV | DNML | OFL | UFL | IMP */
|
|
FPE_FLTDIV, /* 3C - DZ | OFL | UFL | IMP */
|
|
FPE_FLTINV, /* 3D - INV | DZ | OFL | UFL | IMP */
|
|
FPE_FLTDIV, /* 3E - DNML | DZ | OFL | UFL | IMP */
|
|
FPE_FLTINV, /* 3F - INV | DNML | DZ | OFL | UFL | IMP */
|
|
FPE_FLTSUB, /* 40 - STK */
|
|
FPE_FLTSUB, /* 41 - INV | STK */
|
|
FPE_FLTUND, /* 42 - DNML | STK */
|
|
FPE_FLTSUB, /* 43 - INV | DNML | STK */
|
|
FPE_FLTDIV, /* 44 - DZ | STK */
|
|
FPE_FLTSUB, /* 45 - INV | DZ | STK */
|
|
FPE_FLTDIV, /* 46 - DNML | DZ | STK */
|
|
FPE_FLTSUB, /* 47 - INV | DNML | DZ | STK */
|
|
FPE_FLTOVF, /* 48 - OFL | STK */
|
|
FPE_FLTSUB, /* 49 - INV | OFL | STK */
|
|
FPE_FLTUND, /* 4A - DNML | OFL | STK */
|
|
FPE_FLTSUB, /* 4B - INV | DNML | OFL | STK */
|
|
FPE_FLTDIV, /* 4C - DZ | OFL | STK */
|
|
FPE_FLTSUB, /* 4D - INV | DZ | OFL | STK */
|
|
FPE_FLTDIV, /* 4E - DNML | DZ | OFL | STK */
|
|
FPE_FLTSUB, /* 4F - INV | DNML | DZ | OFL | STK */
|
|
FPE_FLTUND, /* 50 - UFL | STK */
|
|
FPE_FLTSUB, /* 51 - INV | UFL | STK */
|
|
FPE_FLTUND, /* 52 - DNML | UFL | STK */
|
|
FPE_FLTSUB, /* 53 - INV | DNML | UFL | STK */
|
|
FPE_FLTDIV, /* 54 - DZ | UFL | STK */
|
|
FPE_FLTSUB, /* 55 - INV | DZ | UFL | STK */
|
|
FPE_FLTDIV, /* 56 - DNML | DZ | UFL | STK */
|
|
FPE_FLTSUB, /* 57 - INV | DNML | DZ | UFL | STK */
|
|
FPE_FLTOVF, /* 58 - OFL | UFL | STK */
|
|
FPE_FLTSUB, /* 59 - INV | OFL | UFL | STK */
|
|
FPE_FLTUND, /* 5A - DNML | OFL | UFL | STK */
|
|
FPE_FLTSUB, /* 5B - INV | DNML | OFL | UFL | STK */
|
|
FPE_FLTDIV, /* 5C - DZ | OFL | UFL | STK */
|
|
FPE_FLTSUB, /* 5D - INV | DZ | OFL | UFL | STK */
|
|
FPE_FLTDIV, /* 5E - DNML | DZ | OFL | UFL | STK */
|
|
FPE_FLTSUB, /* 5F - INV | DNML | DZ | OFL | UFL | STK */
|
|
FPE_FLTRES, /* 60 - IMP | STK */
|
|
FPE_FLTSUB, /* 61 - INV | IMP | STK */
|
|
FPE_FLTUND, /* 62 - DNML | IMP | STK */
|
|
FPE_FLTSUB, /* 63 - INV | DNML | IMP | STK */
|
|
FPE_FLTDIV, /* 64 - DZ | IMP | STK */
|
|
FPE_FLTSUB, /* 65 - INV | DZ | IMP | STK */
|
|
FPE_FLTDIV, /* 66 - DNML | DZ | IMP | STK */
|
|
FPE_FLTSUB, /* 67 - INV | DNML | DZ | IMP | STK */
|
|
FPE_FLTOVF, /* 68 - OFL | IMP | STK */
|
|
FPE_FLTSUB, /* 69 - INV | OFL | IMP | STK */
|
|
FPE_FLTUND, /* 6A - DNML | OFL | IMP | STK */
|
|
FPE_FLTSUB, /* 6B - INV | DNML | OFL | IMP | STK */
|
|
FPE_FLTDIV, /* 6C - DZ | OFL | IMP | STK */
|
|
FPE_FLTSUB, /* 6D - INV | DZ | OFL | IMP | STK */
|
|
FPE_FLTDIV, /* 6E - DNML | DZ | OFL | IMP | STK */
|
|
FPE_FLTSUB, /* 6F - INV | DNML | DZ | OFL | IMP | STK */
|
|
FPE_FLTUND, /* 70 - UFL | IMP | STK */
|
|
FPE_FLTSUB, /* 71 - INV | UFL | IMP | STK */
|
|
FPE_FLTUND, /* 72 - DNML | UFL | IMP | STK */
|
|
FPE_FLTSUB, /* 73 - INV | DNML | UFL | IMP | STK */
|
|
FPE_FLTDIV, /* 74 - DZ | UFL | IMP | STK */
|
|
FPE_FLTSUB, /* 75 - INV | DZ | UFL | IMP | STK */
|
|
FPE_FLTDIV, /* 76 - DNML | DZ | UFL | IMP | STK */
|
|
FPE_FLTSUB, /* 77 - INV | DNML | DZ | UFL | IMP | STK */
|
|
FPE_FLTOVF, /* 78 - OFL | UFL | IMP | STK */
|
|
FPE_FLTSUB, /* 79 - INV | OFL | UFL | IMP | STK */
|
|
FPE_FLTUND, /* 7A - DNML | OFL | UFL | IMP | STK */
|
|
FPE_FLTSUB, /* 7B - INV | DNML | OFL | UFL | IMP | STK */
|
|
FPE_FLTDIV, /* 7C - DZ | OFL | UFL | IMP | STK */
|
|
FPE_FLTSUB, /* 7D - INV | DZ | OFL | UFL | IMP | STK */
|
|
FPE_FLTDIV, /* 7E - DNML | DZ | OFL | UFL | IMP | STK */
|
|
FPE_FLTSUB, /* 7F - INV | DNML | DZ | OFL | UFL | IMP | STK */
|
|
};
|
|
|
|
/*
|
|
* Preserve the FP status word, clear FP exceptions, then generate a SIGFPE.
|
|
*
|
|
* Clearing exceptions is necessary mainly to avoid IRQ13 bugs. We now
|
|
* depend on longjmp() restoring a usable state. Restoring the state
|
|
* or examining it might fail if we didn't clear exceptions.
|
|
*
|
|
* The error code chosen will be one of the FPE_... macros. It will be
|
|
* sent as the second argument to old BSD-style signal handlers and as
|
|
* "siginfo_t->si_code" (second argument) to SA_SIGINFO signal handlers.
|
|
*
|
|
* XXX the FP state is not preserved across signal handlers. So signal
|
|
* handlers cannot afford to do FP unless they preserve the state or
|
|
* longjmp() out. Both preserving the state and longjmp()ing may be
|
|
* destroyed by IRQ13 bugs. Clearing FP exceptions is not an acceptable
|
|
* solution for signals other than SIGFPE.
|
|
*/
|
|
int
|
|
npxtrap()
|
|
{
|
|
critical_t savecrit;
|
|
u_short control, status;
|
|
|
|
if (!npx_exists) {
|
|
printf("npxtrap: npxproc = %p, curproc = %p, npx_exists = %d\n",
|
|
PCPU_GET(npxproc), curproc, npx_exists);
|
|
panic("npxtrap from nowhere");
|
|
}
|
|
savecrit = critical_enter();
|
|
|
|
/*
|
|
* Interrupt handling (for another interrupt) may have pushed the
|
|
* state to memory. Fetch the relevant parts of the state from
|
|
* wherever they are.
|
|
*/
|
|
if (PCPU_GET(npxproc) != curproc) {
|
|
control = curproc->p_addr->u_pcb.pcb_savefpu.sv_env.en_cw;
|
|
status = curproc->p_addr->u_pcb.pcb_savefpu.sv_env.en_sw;
|
|
} else {
|
|
fnstcw(&control);
|
|
fnstsw(&status);
|
|
}
|
|
|
|
curproc->p_addr->u_pcb.pcb_savefpu.sv_ex_sw = status;
|
|
if (PCPU_GET(npxproc) != curproc)
|
|
curproc->p_addr->u_pcb.pcb_savefpu.sv_env.en_sw &= ~0x80bf;
|
|
else
|
|
fnclex();
|
|
critical_exit(savecrit);
|
|
return (fpetable[status & ((~control & 0x3f) | 0x40)]);
|
|
}
|
|
|
|
/*
|
|
* Implement device not available (DNA) exception
|
|
*
|
|
* It would be better to switch FP context here (if curproc != npxproc)
|
|
* and not necessarily for every context switch, but it is too hard to
|
|
* access foreign pcb's.
|
|
*/
|
|
int
|
|
npxdna()
|
|
{
|
|
critical_t s;
|
|
|
|
if (!npx_exists)
|
|
return (0);
|
|
if (PCPU_GET(npxproc) != NULL) {
|
|
printf("npxdna: npxproc = %p, curproc = %p\n",
|
|
PCPU_GET(npxproc), curproc);
|
|
panic("npxdna");
|
|
}
|
|
s = critical_enter();
|
|
stop_emulating();
|
|
/*
|
|
* Record new context early in case frstor causes an IRQ13.
|
|
*/
|
|
PCPU_SET(npxproc, CURPROC);
|
|
PCPU_GET(curpcb)->pcb_savefpu.sv_ex_sw = 0;
|
|
/*
|
|
* The following frstor may cause an IRQ13 when the state being
|
|
* restored has a pending error. The error will appear to have been
|
|
* triggered by the current (npx) user instruction even when that
|
|
* instruction is a no-wait instruction that should not trigger an
|
|
* error (e.g., fnclex). On at least one 486 system all of the
|
|
* no-wait instructions are broken the same as frstor, so our
|
|
* treatment does not amplify the breakage. On at least one
|
|
* 386/Cyrix 387 system, fnclex works correctly while frstor and
|
|
* fnsave are broken, so our treatment breaks fnclex if it is the
|
|
* first FPU instruction after a context switch.
|
|
*/
|
|
frstor(&PCPU_GET(curpcb)->pcb_savefpu);
|
|
critical_exit(s);
|
|
|
|
return (1);
|
|
}
|
|
|
|
/*
|
|
* Wrapper for fnsave instruction, partly to handle hardware bugs. When npx
|
|
* exceptions are reported via IRQ13, spurious IRQ13's may be triggered by
|
|
* no-wait npx instructions. See the Intel application note AP-578 for
|
|
* details. This doesn't cause any additional complications here. IRQ13's
|
|
* are inherently asynchronous unless the CPU is frozen to deliver them --
|
|
* one that started in userland may be delivered many instructions later,
|
|
* after the process has entered the kernel. It may even be delivered after
|
|
* the fnsave here completes. A spurious IRQ13 for the fnsave is handled in
|
|
* the same way as a very-late-arriving non-spurious IRQ13 from user mode:
|
|
* it is normally ignored at first because we set npxproc to NULL; it is
|
|
* normally retriggered in npxdna() after return to user mode.
|
|
*
|
|
* npxsave() must be called with interrupts disabled, so that it clears
|
|
* npxproc atomically with saving the state. We require callers to do the
|
|
* disabling, since most callers need to disable interrupts anyway to call
|
|
* npxsave() atomically with checking npxproc.
|
|
*
|
|
* A previous version of npxsave() went to great lengths to excecute fnsave
|
|
* with interrupts enabled in case executing it froze the CPU. This case
|
|
* can't happen, at least for Intel CPU/NPX's. Spurious IRQ13's don't imply
|
|
* spurious freezes.
|
|
*/
|
|
void
|
|
npxsave(addr)
|
|
struct save87 *addr;
|
|
{
|
|
|
|
stop_emulating();
|
|
fnsave(addr);
|
|
start_emulating();
|
|
PCPU_SET(npxproc, NULL);
|
|
}
|
|
|
|
#ifdef I586_CPU
|
|
static long
|
|
timezero(funcname, func)
|
|
const char *funcname;
|
|
void (*func) __P((void *buf, size_t len));
|
|
|
|
{
|
|
void *buf;
|
|
#define BUFSIZE 1048576
|
|
long usec;
|
|
struct timeval finish, start;
|
|
|
|
buf = malloc(BUFSIZE, M_TEMP, M_NOWAIT);
|
|
if (buf == NULL)
|
|
return (BUFSIZE);
|
|
microtime(&start);
|
|
(*func)(buf, BUFSIZE);
|
|
microtime(&finish);
|
|
usec = 1000000 * (finish.tv_sec - start.tv_sec) +
|
|
finish.tv_usec - start.tv_usec;
|
|
if (usec <= 0)
|
|
usec = 1;
|
|
if (bootverbose)
|
|
printf("%s bandwidth = %lu kBps\n", funcname,
|
|
(u_int32_t)(((BUFSIZE >> 10) * 1000000) / usec));
|
|
free(buf, M_TEMP);
|
|
return (usec);
|
|
}
|
|
#endif /* I586_CPU */
|
|
|
|
static device_method_t npx_methods[] = {
|
|
/* Device interface */
|
|
DEVMETHOD(device_identify, npx_identify),
|
|
DEVMETHOD(device_probe, npx_probe),
|
|
DEVMETHOD(device_attach, npx_attach),
|
|
DEVMETHOD(device_detach, bus_generic_detach),
|
|
DEVMETHOD(device_shutdown, bus_generic_shutdown),
|
|
DEVMETHOD(device_suspend, bus_generic_suspend),
|
|
DEVMETHOD(device_resume, bus_generic_resume),
|
|
|
|
{ 0, 0 }
|
|
};
|
|
|
|
static driver_t npx_driver = {
|
|
"npx",
|
|
npx_methods,
|
|
1, /* no softc */
|
|
};
|
|
|
|
static devclass_t npx_devclass;
|
|
|
|
/*
|
|
* We prefer to attach to the root nexus so that the usual case (exception 16)
|
|
* doesn't describe the processor as being `on isa'.
|
|
*/
|
|
DRIVER_MODULE(npx, nexus, npx_driver, npx_devclass, 0, 0);
|
|
|
|
/*
|
|
* This sucks up the legacy ISA support assignments from PNPBIOS.
|
|
*/
|
|
static struct isa_pnp_id npxisa_ids[] = {
|
|
{ 0x040cd041, "Legacy ISA coprocessor support" }, /* PNP0C04 */
|
|
{ 0 }
|
|
};
|
|
|
|
static int
|
|
npxisa_probe(device_t dev)
|
|
{
|
|
int result;
|
|
if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, npxisa_ids)) <= 0) {
|
|
device_quiet(dev);
|
|
}
|
|
return(result);
|
|
}
|
|
|
|
static int
|
|
npxisa_attach(device_t dev)
|
|
{
|
|
return (0);
|
|
}
|
|
|
|
static device_method_t npxisa_methods[] = {
|
|
/* Device interface */
|
|
DEVMETHOD(device_probe, npxisa_probe),
|
|
DEVMETHOD(device_attach, npxisa_attach),
|
|
DEVMETHOD(device_detach, bus_generic_detach),
|
|
DEVMETHOD(device_shutdown, bus_generic_shutdown),
|
|
DEVMETHOD(device_suspend, bus_generic_suspend),
|
|
DEVMETHOD(device_resume, bus_generic_resume),
|
|
|
|
{ 0, 0 }
|
|
};
|
|
|
|
static driver_t npxisa_driver = {
|
|
"npxisa",
|
|
npxisa_methods,
|
|
1, /* no softc */
|
|
};
|
|
|
|
static devclass_t npxisa_devclass;
|
|
|
|
DRIVER_MODULE(npxisa, isa, npxisa_driver, npxisa_devclass, 0, 0);
|
|
|