b9dda9d6fe
in AMD FPUs: - Do not clear the affected state in the case that the FPU registers for the thread that already owns the FPU are changed via fpu_setregs(). The only local information the thread would see is its own state in that case. - Fix a type mismatch for the dummy variable used in a "fld". It accepts a float, not a double. Reviewed by: bde Approved by: so (cperciva) MFC after: 1 month
578 lines
18 KiB
C
578 lines
18 KiB
C
/*-
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* Copyright (c) 1990 William Jolitz.
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* Copyright (c) 1991 The Regents of the University of California.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* from: @(#)npx.c 7.2 (Berkeley) 5/12/91
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/bus.h>
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#include <sys/kernel.h>
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#include <sys/lock.h>
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#include <sys/malloc.h>
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#include <sys/module.h>
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#include <sys/mutex.h>
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#include <sys/mutex.h>
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#include <sys/proc.h>
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#include <sys/sysctl.h>
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#include <machine/bus.h>
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#include <sys/rman.h>
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#include <sys/signalvar.h>
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#include <machine/cputypes.h>
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#include <machine/frame.h>
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#include <machine/intr_machdep.h>
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#include <machine/md_var.h>
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#include <machine/pcb.h>
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#include <machine/psl.h>
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#include <machine/resource.h>
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#include <machine/specialreg.h>
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#include <machine/segments.h>
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#include <machine/ucontext.h>
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/*
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* Floating point support.
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*/
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#if defined(__GNUCLIKE_ASM) && !defined(lint)
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#define fldcw(addr) __asm("fldcw %0" : : "m" (*(addr)))
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#define fnclex() __asm("fnclex")
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#define fninit() __asm("fninit")
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#define fnstcw(addr) __asm __volatile("fnstcw %0" : "=m" (*(addr)))
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#define fnstsw(addr) __asm __volatile("fnstsw %0" : "=m" (*(addr)))
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#define fxrstor(addr) __asm("fxrstor %0" : : "m" (*(addr)))
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#define fxsave(addr) __asm __volatile("fxsave %0" : "=m" (*(addr)))
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#define ldmxcsr(r) __asm __volatile("ldmxcsr %0" : : "m" (r))
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#define start_emulating() __asm("smsw %%ax; orb %0,%%al; lmsw %%ax" \
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: : "n" (CR0_TS) : "ax")
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#define stop_emulating() __asm("clts")
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#else /* !(__GNUCLIKE_ASM && !lint) */
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void fldcw(caddr_t addr);
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void fnclex(void);
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void fninit(void);
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void fnstcw(caddr_t addr);
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void fnstsw(caddr_t addr);
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void fxsave(caddr_t addr);
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void fxrstor(caddr_t addr);
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void start_emulating(void);
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void stop_emulating(void);
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#endif /* __GNUCLIKE_ASM && !lint */
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#define GET_FPU_CW(thread) ((thread)->td_pcb->pcb_save.sv_env.en_cw)
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#define GET_FPU_SW(thread) ((thread)->td_pcb->pcb_save.sv_env.en_sw)
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typedef u_char bool_t;
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static void fpu_clean_state(void);
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SYSCTL_INT(_hw, HW_FLOATINGPT, floatingpoint, CTLFLAG_RD,
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NULL, 1, "Floating point instructions executed in hardware");
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static struct savefpu fpu_initialstate;
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/*
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* Initialize the floating point unit. On the boot CPU we generate a
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* clean state that is used to initialize the floating point unit when
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* it is first used by a process.
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*/
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void
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fpuinit(void)
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{
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register_t savecrit;
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u_int mxcsr;
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u_short control;
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savecrit = intr_disable();
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stop_emulating();
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fninit();
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control = __INITIAL_FPUCW__;
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fldcw(&control);
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mxcsr = __INITIAL_MXCSR__;
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ldmxcsr(mxcsr);
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if (PCPU_GET(cpuid) == 0) {
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fxsave(&fpu_initialstate);
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if (fpu_initialstate.sv_env.en_mxcsr_mask)
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cpu_mxcsr_mask = fpu_initialstate.sv_env.en_mxcsr_mask;
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else
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cpu_mxcsr_mask = 0xFFBF;
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bzero(fpu_initialstate.sv_fp, sizeof(fpu_initialstate.sv_fp));
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bzero(fpu_initialstate.sv_xmm, sizeof(fpu_initialstate.sv_xmm));
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}
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start_emulating();
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intr_restore(savecrit);
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}
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/*
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* Free coprocessor (if we have it).
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*/
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void
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fpuexit(struct thread *td)
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{
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register_t savecrit;
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savecrit = intr_disable();
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if (curthread == PCPU_GET(fpcurthread)) {
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stop_emulating();
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fxsave(&PCPU_GET(curpcb)->pcb_save);
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start_emulating();
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PCPU_SET(fpcurthread, 0);
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}
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intr_restore(savecrit);
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}
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int
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fpuformat()
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{
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return (_MC_FPFMT_XMM);
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}
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/*
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* The following mechanism is used to ensure that the FPE_... value
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* that is passed as a trapcode to the signal handler of the user
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* process does not have more than one bit set.
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*
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* Multiple bits may be set if the user process modifies the control
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* word while a status word bit is already set. While this is a sign
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* of bad coding, we have no choise than to narrow them down to one
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* bit, since we must not send a trapcode that is not exactly one of
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* the FPE_ macros.
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*
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* The mechanism has a static table with 127 entries. Each combination
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* of the 7 FPU status word exception bits directly translates to a
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* position in this table, where a single FPE_... value is stored.
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* This FPE_... value stored there is considered the "most important"
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* of the exception bits and will be sent as the signal code. The
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* precedence of the bits is based upon Intel Document "Numerical
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* Applications", Chapter "Special Computational Situations".
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*
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* The macro to choose one of these values does these steps: 1) Throw
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* away status word bits that cannot be masked. 2) Throw away the bits
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* currently masked in the control word, assuming the user isn't
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* interested in them anymore. 3) Reinsert status word bit 7 (stack
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* fault) if it is set, which cannot be masked but must be presered.
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* 4) Use the remaining bits to point into the trapcode table.
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*
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* The 6 maskable bits in order of their preference, as stated in the
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* above referenced Intel manual:
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* 1 Invalid operation (FP_X_INV)
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* 1a Stack underflow
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* 1b Stack overflow
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* 1c Operand of unsupported format
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* 1d SNaN operand.
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* 2 QNaN operand (not an exception, irrelavant here)
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* 3 Any other invalid-operation not mentioned above or zero divide
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* (FP_X_INV, FP_X_DZ)
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* 4 Denormal operand (FP_X_DNML)
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* 5 Numeric over/underflow (FP_X_OFL, FP_X_UFL)
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* 6 Inexact result (FP_X_IMP)
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*/
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static char fpetable[128] = {
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0,
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FPE_FLTINV, /* 1 - INV */
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FPE_FLTUND, /* 2 - DNML */
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FPE_FLTINV, /* 3 - INV | DNML */
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FPE_FLTDIV, /* 4 - DZ */
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FPE_FLTINV, /* 5 - INV | DZ */
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FPE_FLTDIV, /* 6 - DNML | DZ */
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FPE_FLTINV, /* 7 - INV | DNML | DZ */
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FPE_FLTOVF, /* 8 - OFL */
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FPE_FLTINV, /* 9 - INV | OFL */
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FPE_FLTUND, /* A - DNML | OFL */
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FPE_FLTINV, /* B - INV | DNML | OFL */
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FPE_FLTDIV, /* C - DZ | OFL */
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FPE_FLTINV, /* D - INV | DZ | OFL */
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FPE_FLTDIV, /* E - DNML | DZ | OFL */
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FPE_FLTINV, /* F - INV | DNML | DZ | OFL */
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FPE_FLTUND, /* 10 - UFL */
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FPE_FLTINV, /* 11 - INV | UFL */
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FPE_FLTUND, /* 12 - DNML | UFL */
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FPE_FLTINV, /* 13 - INV | DNML | UFL */
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FPE_FLTDIV, /* 14 - DZ | UFL */
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FPE_FLTINV, /* 15 - INV | DZ | UFL */
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FPE_FLTDIV, /* 16 - DNML | DZ | UFL */
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FPE_FLTINV, /* 17 - INV | DNML | DZ | UFL */
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FPE_FLTOVF, /* 18 - OFL | UFL */
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FPE_FLTINV, /* 19 - INV | OFL | UFL */
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FPE_FLTUND, /* 1A - DNML | OFL | UFL */
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FPE_FLTINV, /* 1B - INV | DNML | OFL | UFL */
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FPE_FLTDIV, /* 1C - DZ | OFL | UFL */
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FPE_FLTINV, /* 1D - INV | DZ | OFL | UFL */
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FPE_FLTDIV, /* 1E - DNML | DZ | OFL | UFL */
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FPE_FLTINV, /* 1F - INV | DNML | DZ | OFL | UFL */
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FPE_FLTRES, /* 20 - IMP */
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FPE_FLTINV, /* 21 - INV | IMP */
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FPE_FLTUND, /* 22 - DNML | IMP */
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FPE_FLTINV, /* 23 - INV | DNML | IMP */
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FPE_FLTDIV, /* 24 - DZ | IMP */
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FPE_FLTINV, /* 25 - INV | DZ | IMP */
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FPE_FLTDIV, /* 26 - DNML | DZ | IMP */
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FPE_FLTINV, /* 27 - INV | DNML | DZ | IMP */
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FPE_FLTOVF, /* 28 - OFL | IMP */
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FPE_FLTINV, /* 29 - INV | OFL | IMP */
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FPE_FLTUND, /* 2A - DNML | OFL | IMP */
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FPE_FLTINV, /* 2B - INV | DNML | OFL | IMP */
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FPE_FLTDIV, /* 2C - DZ | OFL | IMP */
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FPE_FLTINV, /* 2D - INV | DZ | OFL | IMP */
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FPE_FLTDIV, /* 2E - DNML | DZ | OFL | IMP */
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FPE_FLTINV, /* 2F - INV | DNML | DZ | OFL | IMP */
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FPE_FLTUND, /* 30 - UFL | IMP */
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FPE_FLTINV, /* 31 - INV | UFL | IMP */
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FPE_FLTUND, /* 32 - DNML | UFL | IMP */
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FPE_FLTINV, /* 33 - INV | DNML | UFL | IMP */
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FPE_FLTDIV, /* 34 - DZ | UFL | IMP */
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FPE_FLTINV, /* 35 - INV | DZ | UFL | IMP */
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FPE_FLTDIV, /* 36 - DNML | DZ | UFL | IMP */
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FPE_FLTINV, /* 37 - INV | DNML | DZ | UFL | IMP */
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FPE_FLTOVF, /* 38 - OFL | UFL | IMP */
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FPE_FLTINV, /* 39 - INV | OFL | UFL | IMP */
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FPE_FLTUND, /* 3A - DNML | OFL | UFL | IMP */
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FPE_FLTINV, /* 3B - INV | DNML | OFL | UFL | IMP */
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FPE_FLTDIV, /* 3C - DZ | OFL | UFL | IMP */
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FPE_FLTINV, /* 3D - INV | DZ | OFL | UFL | IMP */
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FPE_FLTDIV, /* 3E - DNML | DZ | OFL | UFL | IMP */
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FPE_FLTINV, /* 3F - INV | DNML | DZ | OFL | UFL | IMP */
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FPE_FLTSUB, /* 40 - STK */
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FPE_FLTSUB, /* 41 - INV | STK */
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FPE_FLTUND, /* 42 - DNML | STK */
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FPE_FLTSUB, /* 43 - INV | DNML | STK */
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FPE_FLTDIV, /* 44 - DZ | STK */
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FPE_FLTSUB, /* 45 - INV | DZ | STK */
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FPE_FLTDIV, /* 46 - DNML | DZ | STK */
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FPE_FLTSUB, /* 47 - INV | DNML | DZ | STK */
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FPE_FLTOVF, /* 48 - OFL | STK */
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FPE_FLTSUB, /* 49 - INV | OFL | STK */
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FPE_FLTUND, /* 4A - DNML | OFL | STK */
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FPE_FLTSUB, /* 4B - INV | DNML | OFL | STK */
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FPE_FLTDIV, /* 4C - DZ | OFL | STK */
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FPE_FLTSUB, /* 4D - INV | DZ | OFL | STK */
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FPE_FLTDIV, /* 4E - DNML | DZ | OFL | STK */
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FPE_FLTSUB, /* 4F - INV | DNML | DZ | OFL | STK */
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FPE_FLTUND, /* 50 - UFL | STK */
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FPE_FLTSUB, /* 51 - INV | UFL | STK */
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FPE_FLTUND, /* 52 - DNML | UFL | STK */
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FPE_FLTSUB, /* 53 - INV | DNML | UFL | STK */
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FPE_FLTDIV, /* 54 - DZ | UFL | STK */
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FPE_FLTSUB, /* 55 - INV | DZ | UFL | STK */
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FPE_FLTDIV, /* 56 - DNML | DZ | UFL | STK */
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FPE_FLTSUB, /* 57 - INV | DNML | DZ | UFL | STK */
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FPE_FLTOVF, /* 58 - OFL | UFL | STK */
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FPE_FLTSUB, /* 59 - INV | OFL | UFL | STK */
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FPE_FLTUND, /* 5A - DNML | OFL | UFL | STK */
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FPE_FLTSUB, /* 5B - INV | DNML | OFL | UFL | STK */
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FPE_FLTDIV, /* 5C - DZ | OFL | UFL | STK */
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FPE_FLTSUB, /* 5D - INV | DZ | OFL | UFL | STK */
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FPE_FLTDIV, /* 5E - DNML | DZ | OFL | UFL | STK */
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FPE_FLTSUB, /* 5F - INV | DNML | DZ | OFL | UFL | STK */
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FPE_FLTRES, /* 60 - IMP | STK */
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FPE_FLTSUB, /* 61 - INV | IMP | STK */
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FPE_FLTUND, /* 62 - DNML | IMP | STK */
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FPE_FLTSUB, /* 63 - INV | DNML | IMP | STK */
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FPE_FLTDIV, /* 64 - DZ | IMP | STK */
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FPE_FLTSUB, /* 65 - INV | DZ | IMP | STK */
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FPE_FLTDIV, /* 66 - DNML | DZ | IMP | STK */
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FPE_FLTSUB, /* 67 - INV | DNML | DZ | IMP | STK */
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FPE_FLTOVF, /* 68 - OFL | IMP | STK */
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FPE_FLTSUB, /* 69 - INV | OFL | IMP | STK */
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FPE_FLTUND, /* 6A - DNML | OFL | IMP | STK */
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FPE_FLTSUB, /* 6B - INV | DNML | OFL | IMP | STK */
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FPE_FLTDIV, /* 6C - DZ | OFL | IMP | STK */
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FPE_FLTSUB, /* 6D - INV | DZ | OFL | IMP | STK */
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FPE_FLTDIV, /* 6E - DNML | DZ | OFL | IMP | STK */
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FPE_FLTSUB, /* 6F - INV | DNML | DZ | OFL | IMP | STK */
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FPE_FLTUND, /* 70 - UFL | IMP | STK */
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FPE_FLTSUB, /* 71 - INV | UFL | IMP | STK */
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FPE_FLTUND, /* 72 - DNML | UFL | IMP | STK */
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FPE_FLTSUB, /* 73 - INV | DNML | UFL | IMP | STK */
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FPE_FLTDIV, /* 74 - DZ | UFL | IMP | STK */
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FPE_FLTSUB, /* 75 - INV | DZ | UFL | IMP | STK */
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FPE_FLTDIV, /* 76 - DNML | DZ | UFL | IMP | STK */
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FPE_FLTSUB, /* 77 - INV | DNML | DZ | UFL | IMP | STK */
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FPE_FLTOVF, /* 78 - OFL | UFL | IMP | STK */
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FPE_FLTSUB, /* 79 - INV | OFL | UFL | IMP | STK */
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FPE_FLTUND, /* 7A - DNML | OFL | UFL | IMP | STK */
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FPE_FLTSUB, /* 7B - INV | DNML | OFL | UFL | IMP | STK */
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FPE_FLTDIV, /* 7C - DZ | OFL | UFL | IMP | STK */
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FPE_FLTSUB, /* 7D - INV | DZ | OFL | UFL | IMP | STK */
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FPE_FLTDIV, /* 7E - DNML | DZ | OFL | UFL | IMP | STK */
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FPE_FLTSUB, /* 7F - INV | DNML | DZ | OFL | UFL | IMP | STK */
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};
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/*
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* Preserve the FP status word, clear FP exceptions, then generate a SIGFPE.
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*
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* Clearing exceptions is necessary mainly to avoid IRQ13 bugs. We now
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* depend on longjmp() restoring a usable state. Restoring the state
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* or examining it might fail if we didn't clear exceptions.
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*
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* The error code chosen will be one of the FPE_... macros. It will be
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* sent as the second argument to old BSD-style signal handlers and as
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* "siginfo_t->si_code" (second argument) to SA_SIGINFO signal handlers.
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*
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* XXX the FP state is not preserved across signal handlers. So signal
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* handlers cannot afford to do FP unless they preserve the state or
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* longjmp() out. Both preserving the state and longjmp()ing may be
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* destroyed by IRQ13 bugs. Clearing FP exceptions is not an acceptable
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* solution for signals other than SIGFPE.
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*/
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int
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fputrap()
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{
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register_t savecrit;
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u_short control, status;
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savecrit = intr_disable();
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/*
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* Interrupt handling (for another interrupt) may have pushed the
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* state to memory. Fetch the relevant parts of the state from
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* wherever they are.
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*/
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if (PCPU_GET(fpcurthread) != curthread) {
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control = GET_FPU_CW(curthread);
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status = GET_FPU_SW(curthread);
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} else {
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fnstcw(&control);
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fnstsw(&status);
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}
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if (PCPU_GET(fpcurthread) == curthread)
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fnclex();
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intr_restore(savecrit);
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return (fpetable[status & ((~control & 0x3f) | 0x40)]);
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}
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/*
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* Implement device not available (DNA) exception
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*
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* It would be better to switch FP context here (if curthread != fpcurthread)
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|
* and not necessarily for every context switch, but it is too hard to
|
|
* access foreign pcb's.
|
|
*/
|
|
|
|
static int err_count = 0;
|
|
|
|
void
|
|
fpudna(void)
|
|
{
|
|
struct pcb *pcb;
|
|
register_t s;
|
|
|
|
if (PCPU_GET(fpcurthread) == curthread) {
|
|
printf("fpudna: fpcurthread == curthread %d times\n",
|
|
++err_count);
|
|
stop_emulating();
|
|
return;
|
|
}
|
|
if (PCPU_GET(fpcurthread) != NULL) {
|
|
printf("fpudna: fpcurthread = %p (%d), curthread = %p (%d)\n",
|
|
PCPU_GET(fpcurthread),
|
|
PCPU_GET(fpcurthread)->td_proc->p_pid,
|
|
curthread, curthread->td_proc->p_pid);
|
|
panic("fpudna");
|
|
}
|
|
s = intr_disable();
|
|
stop_emulating();
|
|
/*
|
|
* Record new context early in case frstor causes a trap.
|
|
*/
|
|
PCPU_SET(fpcurthread, curthread);
|
|
pcb = PCPU_GET(curpcb);
|
|
|
|
fpu_clean_state();
|
|
|
|
if ((pcb->pcb_flags & PCB_FPUINITDONE) == 0) {
|
|
/*
|
|
* This is the first time this thread has used the FPU or
|
|
* the PCB doesn't contain a clean FPU state. Explicitly
|
|
* load an initial state.
|
|
*/
|
|
fxrstor(&fpu_initialstate);
|
|
if (pcb->pcb_initial_fpucw != __INITIAL_FPUCW__)
|
|
fldcw(&pcb->pcb_initial_fpucw);
|
|
pcb->pcb_flags |= PCB_FPUINITDONE;
|
|
} else
|
|
fxrstor(&pcb->pcb_save);
|
|
intr_restore(s);
|
|
}
|
|
|
|
/*
|
|
* This should be called with interrupts disabled and only when the owning
|
|
* FPU thread is non-null.
|
|
*/
|
|
void
|
|
fpudrop()
|
|
{
|
|
struct thread *td;
|
|
|
|
td = PCPU_GET(fpcurthread);
|
|
PCPU_SET(fpcurthread, NULL);
|
|
td->td_pcb->pcb_flags &= ~PCB_FPUINITDONE;
|
|
start_emulating();
|
|
}
|
|
|
|
/*
|
|
* Get the state of the FPU without dropping ownership (if possible).
|
|
* It returns the FPU ownership status.
|
|
*/
|
|
int
|
|
fpugetregs(struct thread *td, struct savefpu *addr)
|
|
{
|
|
register_t s;
|
|
|
|
if ((td->td_pcb->pcb_flags & PCB_FPUINITDONE) == 0) {
|
|
bcopy(&fpu_initialstate, addr, sizeof(fpu_initialstate));
|
|
addr->sv_env.en_cw = td->td_pcb->pcb_initial_fpucw;
|
|
return (_MC_FPOWNED_NONE);
|
|
}
|
|
s = intr_disable();
|
|
if (td == PCPU_GET(fpcurthread)) {
|
|
fxsave(addr);
|
|
intr_restore(s);
|
|
return (_MC_FPOWNED_FPU);
|
|
} else {
|
|
intr_restore(s);
|
|
bcopy(&td->td_pcb->pcb_save, addr, sizeof(*addr));
|
|
return (_MC_FPOWNED_PCB);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Set the state of the FPU.
|
|
*/
|
|
void
|
|
fpusetregs(struct thread *td, struct savefpu *addr)
|
|
{
|
|
register_t s;
|
|
|
|
s = intr_disable();
|
|
if (td == PCPU_GET(fpcurthread)) {
|
|
fxrstor(addr);
|
|
intr_restore(s);
|
|
} else {
|
|
intr_restore(s);
|
|
bcopy(addr, &td->td_pcb->pcb_save, sizeof(*addr));
|
|
}
|
|
curthread->td_pcb->pcb_flags |= PCB_FPUINITDONE;
|
|
}
|
|
|
|
/*
|
|
* On AuthenticAMD processors, the fxrstor instruction does not restore
|
|
* the x87's stored last instruction pointer, last data pointer, and last
|
|
* opcode values, except in the rare case in which the exception summary
|
|
* (ES) bit in the x87 status word is set to 1.
|
|
*
|
|
* In order to avoid leaking this information across processes, we clean
|
|
* these values by performing a dummy load before executing fxrstor().
|
|
*/
|
|
static void
|
|
fpu_clean_state(void)
|
|
{
|
|
static float dummy_variable = 0.0;
|
|
u_short status;
|
|
|
|
/*
|
|
* Clear the ES bit in the x87 status word if it is currently
|
|
* set, in order to avoid causing a fault in the upcoming load.
|
|
*/
|
|
fnstsw(&status);
|
|
if (status & 0x80)
|
|
fnclex();
|
|
|
|
/*
|
|
* Load the dummy variable into the x87 stack. This mangles
|
|
* the x87 stack, but we don't care since we're about to call
|
|
* fxrstor() anyway.
|
|
*/
|
|
__asm __volatile("ffree %%st(7); fld %0" : : "m" (dummy_variable));
|
|
}
|
|
|
|
/*
|
|
* This really sucks. We want the acpi version only, but it requires
|
|
* the isa_if.h file in order to get the definitions.
|
|
*/
|
|
#include "opt_isa.h"
|
|
#ifdef DEV_ISA
|
|
#include <isa/isavar.h>
|
|
/*
|
|
* This sucks up the legacy ISA support assignments from PNPBIOS/ACPI.
|
|
*/
|
|
static struct isa_pnp_id fpupnp_ids[] = {
|
|
{ 0x040cd041, "Legacy ISA coprocessor support" }, /* PNP0C04 */
|
|
{ 0 }
|
|
};
|
|
|
|
static int
|
|
fpupnp_probe(device_t dev)
|
|
{
|
|
int result;
|
|
|
|
result = ISA_PNP_PROBE(device_get_parent(dev), dev, fpupnp_ids);
|
|
if (result <= 0)
|
|
device_quiet(dev);
|
|
return (result);
|
|
}
|
|
|
|
static int
|
|
fpupnp_attach(device_t dev)
|
|
{
|
|
|
|
return (0);
|
|
}
|
|
|
|
static device_method_t fpupnp_methods[] = {
|
|
/* Device interface */
|
|
DEVMETHOD(device_probe, fpupnp_probe),
|
|
DEVMETHOD(device_attach, fpupnp_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 fpupnp_driver = {
|
|
"fpupnp",
|
|
fpupnp_methods,
|
|
1, /* no softc */
|
|
};
|
|
|
|
static devclass_t fpupnp_devclass;
|
|
|
|
DRIVER_MODULE(fpupnp, acpi, fpupnp_driver, fpupnp_devclass, 0, 0);
|
|
#endif /* DEV_ISA */
|