freebsd-dev/sys/sparc64/sparc64/machdep.c
David Xu b8f480ab94 Add a machine depended function thread_siginfo, SA signal code
will use the function to construct a siginfo structure and use
the result to export to userland.

Reviewed by: julian
2003-06-28 06:34:08 +00:00

797 lines
18 KiB
C

/*-
* Copyright (c) 2001 Jake Burkholder.
* Copyright (c) 1992 Terrence R. Lambert.
* Copyright (c) 1982, 1987, 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* 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: @(#)machdep.c 7.4 (Berkeley) 6/3/91
* from: FreeBSD: src/sys/i386/i386/machdep.c,v 1.477 2001/08/27
* $FreeBSD$
*/
#include "opt_compat.h"
#include "opt_ddb.h"
#include "opt_msgbuf.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/cons.h>
#include <sys/imgact.h>
#include <sys/kernel.h>
#include <sys/ktr.h>
#include <sys/linker.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/msgbuf.h>
#include <sys/mutex.h>
#include <sys/pcpu.h>
#include <sys/proc.h>
#include <sys/reboot.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/bus.h>
#include <sys/eventhandler.h>
#include <sys/interrupt.h>
#include <sys/ptrace.h>
#include <sys/signalvar.h>
#include <sys/smp.h>
#include <sys/sysent.h>
#include <sys/sysproto.h>
#include <sys/timetc.h>
#include <sys/user.h>
#include <sys/ucontext.h>
#include <sys/user.h>
#include <sys/ucontext.h>
#include <sys/exec.h>
#include <dev/ofw/openfirm.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_pager.h>
#include <vm/vm_extern.h>
#include <ddb/ddb.h>
#include <machine/cache.h>
#include <machine/clock.h>
#include <machine/cpu.h>
#include <machine/fp.h>
#include <machine/fsr.h>
#include <machine/intr_machdep.h>
#include <machine/md_var.h>
#include <machine/metadata.h>
#include <machine/ofw_machdep.h>
#include <machine/ofw_mem.h>
#include <machine/smp.h>
#include <machine/pmap.h>
#include <machine/pstate.h>
#include <machine/reg.h>
#include <machine/sigframe.h>
#include <machine/tick.h>
#include <machine/tlb.h>
#include <machine/tstate.h>
#include <machine/upa.h>
#include <machine/ver.h>
typedef int ofw_vec_t(void *);
struct tlb_entry *kernel_tlbs;
int kernel_tlb_slots;
int cold = 1;
long Maxmem;
char pcpu0[PCPU_PAGES * PAGE_SIZE];
char uarea0[UAREA_PAGES * PAGE_SIZE];
struct trapframe frame0;
vm_offset_t kstack0;
vm_paddr_t kstack0_phys;
struct kva_md_info kmi;
u_long ofw_vec;
u_long ofw_tba;
static struct timecounter tick_tc;
char sparc64_model[32];
static int cpu_use_vis = 1;
cpu_block_copy_t *cpu_block_copy;
cpu_block_zero_t *cpu_block_zero;
static timecounter_get_t tick_get_timecount;
void sparc64_init(caddr_t mdp, u_long o1, u_long o2, u_long o3,
ofw_vec_t *vec);
void sparc64_shutdown_final(void *dummy, int howto);
static void cpu_startup(void *);
SYSINIT(cpu, SI_SUB_CPU, SI_ORDER_FIRST, cpu_startup, NULL);
CTASSERT((1 << INT_SHIFT) == sizeof(int));
CTASSERT((1 << PTR_SHIFT) == sizeof(char *));
CTASSERT(sizeof(struct reg) == 256);
CTASSERT(sizeof(struct fpreg) == 272);
CTASSERT(sizeof(struct __mcontext) == 512);
CTASSERT((sizeof(struct pcb) & (64 - 1)) == 0);
CTASSERT((offsetof(struct pcb, pcb_kfp) & (64 - 1)) == 0);
CTASSERT((offsetof(struct pcb, pcb_ufp) & (64 - 1)) == 0);
CTASSERT(sizeof(struct pcb) <= ((KSTACK_PAGES * PAGE_SIZE) / 8));
CTASSERT(sizeof(struct pcpu) <= ((PCPU_PAGES * PAGE_SIZE) / 2));
static void
cpu_startup(void *arg)
{
vm_paddr_t physsz;
int i;
tick_tc.tc_get_timecount = tick_get_timecount;
tick_tc.tc_poll_pps = NULL;
tick_tc.tc_counter_mask = ~0u;
tick_tc.tc_frequency = tick_freq;
tick_tc.tc_name = "tick";
tc_init(&tick_tc);
physsz = 0;
for (i = 0; i < sparc64_nmemreg; i++)
physsz += sparc64_memreg[i].mr_size;
printf("real memory = %lu (%lu MB)\n", physsz,
physsz / (1024 * 1024));
vm_ksubmap_init(&kmi);
bufinit();
vm_pager_bufferinit();
EVENTHANDLER_REGISTER(shutdown_final, sparc64_shutdown_final, NULL,
SHUTDOWN_PRI_LAST);
printf("avail memory = %lu (%lu MB)\n", cnt.v_free_count * PAGE_SIZE,
cnt.v_free_count / ((1024 * 1024) / PAGE_SIZE));
if (bootverbose)
printf("machine: %s\n", sparc64_model);
cpu_identify(rdpr(ver), tick_freq, PCPU_GET(cpuid));
}
void
cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t size)
{
struct intr_request *ir;
int i;
pcpu->pc_irtail = &pcpu->pc_irhead;
for (i = 0; i < IR_FREE; i++) {
ir = &pcpu->pc_irpool[i];
ir->ir_next = pcpu->pc_irfree;
pcpu->pc_irfree = ir;
}
}
unsigned
tick_get_timecount(struct timecounter *tc)
{
return ((unsigned)rd(tick));
}
void
sparc64_init(caddr_t mdp, u_long o1, u_long o2, u_long o3, ofw_vec_t *vec)
{
phandle_t child;
phandle_t root;
struct pcpu *pc;
vm_offset_t end;
caddr_t kmdp;
u_int clock;
char *env;
char type[8];
end = 0;
kmdp = NULL;
/*
* Find out what kind of cpu we have first, for anything that changes
* behaviour.
*/
cpu_impl = VER_IMPL(rdpr(ver));
/*
* Initialize openfirmware (needed for console).
*/
OF_init(vec);
/*
* Parse metadata if present and fetch parameters. Must be before the
* console is inited so cninit gets the right value of boothowto.
*/
if (mdp != NULL) {
preload_metadata = mdp;
kmdp = preload_search_by_type("elf kernel");
if (kmdp != NULL) {
boothowto = MD_FETCH(kmdp, MODINFOMD_HOWTO, int);
kern_envp = MD_FETCH(kmdp, MODINFOMD_ENVP, char *);
end = MD_FETCH(kmdp, MODINFOMD_KERNEND, vm_offset_t);
kernel_tlb_slots = MD_FETCH(kmdp, MODINFOMD_DTLB_SLOTS,
int);
kernel_tlbs = (void *)preload_search_info(kmdp,
MODINFO_METADATA | MODINFOMD_DTLB);
}
}
/*
* Initialize the console before printing anything.
*/
cninit();
/*
* Panic is there is no metadata. Most likely the kernel was booted
* directly, instead of through loader(8).
*/
if (mdp == NULL || kmdp == NULL) {
printf("sparc64_init: no loader metadata.\n"
"This probably means you are not using loader(8).\n");
panic("sparc64_init");
}
/*
* Sanity check the kernel end, which is important.
*/
if (end == 0) {
printf("sparc64_init: warning, kernel end not specified.\n"
"Attempting to continue anyway.\n");
end = (vm_offset_t)_end;
}
root = OF_peer(0);
for (child = OF_child(root); child != 0; child = OF_peer(child)) {
OF_getprop(child, "device_type", type, sizeof(type));
if (strcmp(type, "cpu") == 0)
break;
}
if (child == 0)
panic("cpu_startup: no cpu\n");
cache_init(child);
getenv_int("machdep.use_vis", &cpu_use_vis);
if (cpu_use_vis) {
cpu_block_copy = spitfire_block_copy;
cpu_block_zero = spitfire_block_zero;
} else {
cpu_block_copy = bcopy;
cpu_block_zero = bzero;
}
#ifdef DDB
kdb_init();
#endif
#ifdef SMP
mp_tramp = mp_tramp_alloc();
#endif
/*
* Initialize virtual memory and calculate physmem.
*/
pmap_bootstrap(end);
/*
* Initialize tunables.
*/
init_param1();
init_param2(physmem);
env = getenv("kernelname");
if (env != NULL) {
strlcpy(kernelname, env, sizeof(kernelname));
freeenv(env);
}
/*
* Disable tick for now.
*/
tick_stop();
/*
* Initialize the interrupt tables.
*/
intr_init1();
/*
* Initialize proc0 stuff (p_contested needs to be done early).
*/
proc_linkup(&proc0, &ksegrp0, &kse0, &thread0);
proc0.p_md.md_sigtramp = NULL;
proc0.p_md.md_utrap = NULL;
proc0.p_uarea = (struct user *)uarea0;
proc0.p_stats = &proc0.p_uarea->u_stats;
thread0.td_kstack = kstack0;
thread0.td_pcb = (struct pcb *)
(thread0.td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1;
frame0.tf_tstate = TSTATE_IE | TSTATE_PEF | TSTATE_PRIV;
thread0.td_frame = &frame0;
/*
* Prime our per-cpu data page for use. Note, we are using it for our
* stack, so don't pass the real size (PAGE_SIZE) to pcpu_init or
* it'll zero it out from under us.
*/
pc = (struct pcpu *)(pcpu0 + (PCPU_PAGES * PAGE_SIZE)) - 1;
pcpu_init(pc, 0, sizeof(struct pcpu));
pc->pc_curthread = &thread0;
pc->pc_curpcb = thread0.td_pcb;
pc->pc_mid = UPA_CR_GET_MID(ldxa(0, ASI_UPA_CONFIG_REG));
pc->pc_addr = (vm_offset_t)pcpu0;
pc->pc_node = child;
pc->pc_tlb_ctx = TLB_CTX_USER_MIN;
pc->pc_tlb_ctx_min = TLB_CTX_USER_MIN;
pc->pc_tlb_ctx_max = TLB_CTX_USER_MAX;
/*
* Initialize global registers.
*/
cpu_setregs(pc);
/*
* Initialize the message buffer (after setting trap table).
*/
msgbufinit(msgbufp, MSGBUF_SIZE);
mutex_init();
intr_init2();
OF_getprop(PCPU_GET(node), "clock-frequency", &clock, sizeof(clock));
tick_init(clock);
OF_getprop(root, "name", sparc64_model, sizeof(sparc64_model) - 1);
}
void
set_openfirm_callback(ofw_vec_t *vec)
{
ofw_tba = rdpr(tba);
ofw_vec = (u_long)vec;
}
void
sendsig(sig_t catcher, int sig, sigset_t *mask, u_long code)
{
struct trapframe *tf;
struct sigframe *sfp;
struct sigacts *psp;
struct sigframe sf;
struct thread *td;
struct frame *fp;
struct proc *p;
int oonstack;
u_long sp;
oonstack = 0;
td = curthread;
p = td->td_proc;
PROC_LOCK_ASSERT(p, MA_OWNED);
psp = p->p_sigacts;
mtx_assert(&psp->ps_mtx, MA_OWNED);
tf = td->td_frame;
sp = tf->tf_sp + SPOFF;
oonstack = sigonstack(sp);
CTR4(KTR_SIG, "sendsig: td=%p (%s) catcher=%p sig=%d", td, p->p_comm,
catcher, sig);
/* Make sure we have a signal trampoline to return to. */
if (p->p_md.md_sigtramp == NULL) {
/*
* No signal tramoline... kill the process.
*/
CTR0(KTR_SIG, "sendsig: no sigtramp");
printf("sendsig: %s is too old, rebuild it\n", p->p_comm);
sigexit(td, sig);
/* NOTREACHED */
}
/* Save user context. */
bzero(&sf, sizeof(sf));
sf.sf_uc.uc_sigmask = *mask;
sf.sf_uc.uc_stack = p->p_sigstk;
sf.sf_uc.uc_stack.ss_flags = (p->p_flag & P_ALTSTACK)
? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
bcopy(tf, &sf.sf_uc.uc_mcontext, sizeof(*tf));
/* Allocate and validate space for the signal handler context. */
if ((p->p_flag & P_ALTSTACK) != 0 && !oonstack &&
SIGISMEMBER(psp->ps_sigonstack, sig)) {
sfp = (struct sigframe *)(p->p_sigstk.ss_sp +
p->p_sigstk.ss_size - sizeof(struct sigframe));
} else
sfp = (struct sigframe *)sp - 1;
mtx_unlock(&psp->ps_mtx);
PROC_UNLOCK(p);
fp = (struct frame *)sfp - 1;
/* Translate the signal if appropriate. */
if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
/* Build the argument list for the signal handler. */
tf->tf_out[0] = sig;
tf->tf_out[1] = (register_t)&sfp->sf_si;
tf->tf_out[2] = (register_t)&sfp->sf_uc;
tf->tf_out[4] = (register_t)catcher;
/* Fill siginfo structure. */
sf.sf_si.si_signo = sig;
sf.sf_si.si_code = code;
sf.sf_si.si_addr = (void *)tf->tf_sfar;
/* Copy the sigframe out to the user's stack. */
if (rwindow_save(td) != 0 || copyout(&sf, sfp, sizeof(*sfp)) != 0 ||
suword(&fp->fr_in[6], tf->tf_out[6]) != 0) {
/*
* Something is wrong with the stack pointer.
* ...Kill the process.
*/
CTR2(KTR_SIG, "sendsig: sigexit td=%p sfp=%p", td, sfp);
PROC_LOCK(p);
sigexit(td, SIGILL);
/* NOTREACHED */
}
tf->tf_tpc = (u_long)p->p_md.md_sigtramp;
tf->tf_tnpc = tf->tf_tpc + 4;
tf->tf_sp = (u_long)fp - SPOFF;
CTR3(KTR_SIG, "sendsig: return td=%p pc=%#lx sp=%#lx", td, tf->tf_tpc,
tf->tf_sp);
PROC_LOCK(p);
mtx_lock(&psp->ps_mtx);
}
/*
* Build siginfo_t for SA thread
*/
void
thread_siginfo(int sig, u_long code, siginfo_t *si)
{
struct proc *p;
struct thread *td;
td = curthread;
p = td->td_proc;
PROC_LOCK_ASSERT(p, MA_OWNED);
bzero(si, sizeof(*si));
si->si_signo = sig;
si->si_code = code;
/* XXXKSE fill other fields */
}
#ifndef _SYS_SYSPROTO_H_
struct sigreturn_args {
ucontext_t *ucp;
};
#endif
/*
* MPSAFE
*/
int
sigreturn(struct thread *td, struct sigreturn_args *uap)
{
struct trapframe *tf;
struct proc *p;
mcontext_t *mc;
ucontext_t uc;
p = td->td_proc;
if (rwindow_save(td)) {
PROC_LOCK(p);
sigexit(td, SIGILL);
}
CTR2(KTR_SIG, "sigreturn: td=%p ucp=%p", td, uap->sigcntxp);
if (copyin(uap->sigcntxp, &uc, sizeof(uc)) != 0) {
CTR1(KTR_SIG, "sigreturn: efault td=%p", td);
return (EFAULT);
}
mc = &uc.uc_mcontext;
tf = td->td_frame;
if (!TSTATE_SECURE(mc->mc_tstate))
return (EINVAL);
mc->mc_wstate = tf->tf_wstate;
bcopy(mc, tf, sizeof(*tf));
PROC_LOCK(p);
td->td_sigmask = uc.uc_sigmask;
SIG_CANTMASK(td->td_sigmask);
signotify(td);
PROC_UNLOCK(p);
CTR4(KTR_SIG, "sigreturn: return td=%p pc=%#lx sp=%#lx tstate=%#lx",
td, tf->tf_tpc, tf->tf_sp, tf->tf_tstate);
return (EJUSTRETURN);
}
#ifdef COMPAT_FREEBSD4
int
freebsd4_sigreturn(struct thread *td, struct freebsd4_sigreturn_args *uap)
{
return sigreturn(td, (struct sigreturn_args *)uap);
}
#endif
int
get_mcontext(struct thread *td, mcontext_t *mc, int clear_ret)
{
struct trapframe *tf;
struct pcb *pcb;
tf = td->td_frame;
pcb = td->td_pcb;
bcopy(tf, mc, sizeof(*tf));
if (clear_ret != 0) {
mc->mc_out[0] = 0;
mc->mc_out[1] = 0;
}
mc->mc_flags = _MC_VERSION;
critical_enter();
if ((tf->tf_fprs & FPRS_FEF) != 0) {
savefpctx(pcb->pcb_ufp);
tf->tf_fprs &= ~FPRS_FEF;
pcb->pcb_flags |= PCB_FEF;
}
if ((pcb->pcb_flags & PCB_FEF) != 0) {
bcopy(pcb->pcb_ufp, mc->mc_fp, sizeof(mc->mc_fp));
mc->mc_fprs |= FPRS_FEF;
}
critical_exit();
return (0);
}
int
set_mcontext(struct thread *td, const mcontext_t *mc)
{
struct trapframe *tf;
struct pcb *pcb;
uint64_t wstate;
if (!TSTATE_SECURE(mc->mc_tstate) ||
(mc->mc_flags & ((1L << _MC_VERSION_BITS) - 1)) != _MC_VERSION)
return (EINVAL);
tf = td->td_frame;
pcb = td->td_pcb;
wstate = tf->tf_wstate;
bcopy(mc, tf, sizeof(*tf));
tf->tf_wstate = wstate;
if ((mc->mc_fprs & FPRS_FEF) != 0) {
tf->tf_fprs = 0;
bcopy(mc->mc_fp, pcb->pcb_ufp, sizeof(pcb->pcb_ufp));
pcb->pcb_flags |= PCB_FEF;
}
return (0);
}
/*
* Exit the kernel and execute a firmware call that will not return, as
* specified by the arguments.
*/
void
cpu_shutdown(void *args)
{
#ifdef SMP
cpu_mp_shutdown();
#endif
openfirmware_exit(args);
}
/*
* Duplicate OF_exit() with a different firmware call function that restores
* the trap table, otherwise a RED state exception is triggered in at least
* some firmware versions.
*/
void
cpu_halt(void)
{
static struct {
cell_t name;
cell_t nargs;
cell_t nreturns;
} args = {
(cell_t)"exit",
0,
0
};
cpu_shutdown(&args);
}
void
sparc64_shutdown_final(void *dummy, int howto)
{
static struct {
cell_t name;
cell_t nargs;
cell_t nreturns;
} args = {
(cell_t)"SUNW,power-off",
0,
0
};
/* Turn the power off? */
if ((howto & RB_POWEROFF) != 0)
cpu_shutdown(&args);
/* In case of halt, return to the firmware */
if ((howto & RB_HALT) != 0)
cpu_halt();
}
int
ptrace_set_pc(struct thread *td, u_long addr)
{
td->td_frame->tf_tpc = addr;
td->td_frame->tf_tnpc = addr + 4;
return (0);
}
int
ptrace_single_step(struct thread *td)
{
/* TODO; */
return (0);
}
void
exec_setregs(struct thread *td, u_long entry, u_long stack, u_long ps_strings)
{
struct trapframe *tf;
struct md_utrap *ut;
struct pcb *pcb;
struct proc *p;
u_long sp;
/* XXX no cpu_exec */
p = td->td_proc;
p->p_md.md_sigtramp = NULL;
if ((ut = p->p_md.md_utrap) != NULL) {
ut->ut_refcnt--;
if (ut->ut_refcnt == 0)
free(ut, M_SUBPROC);
p->p_md.md_utrap = NULL;
}
pcb = td->td_pcb;
tf = td->td_frame;
sp = rounddown(stack, 16);
bzero(pcb, sizeof(*pcb));
bzero(tf, sizeof(*tf));
tf->tf_out[0] = stack;
tf->tf_out[3] = p->p_sysent->sv_psstrings;
tf->tf_out[6] = sp - SPOFF - sizeof(struct frame);
tf->tf_tnpc = entry + 4;
tf->tf_tpc = entry;
tf->tf_tstate = TSTATE_IE | TSTATE_PEF | TSTATE_MM_TSO;
td->td_retval[0] = tf->tf_out[0];
td->td_retval[1] = tf->tf_out[1];
}
void
Debugger(const char *msg)
{
printf("Debugger(\"%s\")\n", msg);
critical_enter();
breakpoint();
critical_exit();
}
int
fill_regs(struct thread *td, struct reg *regs)
{
bcopy(td->td_frame, regs, sizeof(*regs));
return (0);
}
int
set_regs(struct thread *td, struct reg *regs)
{
struct trapframe *tf;
if (!TSTATE_SECURE(regs->r_tstate))
return (EINVAL);
tf = td->td_frame;
regs->r_wstate = tf->tf_wstate;
bcopy(regs, tf, sizeof(*regs));
return (0);
}
int
fill_dbregs(struct thread *td, struct dbreg *dbregs)
{
return (ENOSYS);
}
int
set_dbregs(struct thread *td, struct dbreg *dbregs)
{
return (ENOSYS);
}
int
fill_fpregs(struct thread *td, struct fpreg *fpregs)
{
struct trapframe *tf;
struct pcb *pcb;
pcb = td->td_pcb;
tf = td->td_frame;
bcopy(pcb->pcb_ufp, fpregs->fr_regs, sizeof(fpregs->fr_regs));
fpregs->fr_fsr = tf->tf_fsr;
fpregs->fr_gsr = tf->tf_gsr;
return (0);
}
int
set_fpregs(struct thread *td, struct fpreg *fpregs)
{
struct trapframe *tf;
struct pcb *pcb;
pcb = td->td_pcb;
tf = td->td_frame;
tf->tf_fprs &= ~FPRS_FEF;
bcopy(fpregs->fr_regs, pcb->pcb_ufp, sizeof(pcb->pcb_ufp));
tf->tf_fsr = fpregs->fr_fsr;
tf->tf_gsr = fpregs->fr_gsr;
return (0);
}