/* $NetBSD: fpu.c,v 1.8 2005/12/24 22:45:33 perry Exp $ */ /*- * Copyright (c) 2000, 2001 Ben Harris * 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. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. */ /* * fpu.c - Floating point unit support */ #include <sys/param.h> __KERNEL_RCSID(0, "$NetBSD: fpu.c,v 1.8 2005/12/24 22:45:33 perry Exp $"); #include <sys/device.h> #include <sys/proc.h> #include <sys/systm.h> #include <sys/user.h> #include <arm/undefined.h> #include <machine/fpureg.h> #include <machine/pcb.h> #include <arch/acorn26/acorn26/fpuvar.h> #include "opt_fputypes.h" static int fpu_match(struct device *, struct cfdata *, void *); static void fpu_attach(struct device *, struct device *, void *); static register_t fpu_identify(void); CFATTACH_DECL(fpu, sizeof(struct fpu_softc), fpu_match, fpu_attach, NULL, NULL); struct fpu_softc *the_fpu; static int fpu_match(struct device *parent, struct cfdata *cf, void *aux) { return the_fpu == NULL && fpu_identify() != 0; } static void fpu_attach(struct device *parent, struct device *self, void *aux) { int supported; struct fpu_softc *sc = (void *)self; the_fpu = sc; printf(": "); sc->sc_fputype = fpu_identify(); supported = 0; switch (sc->sc_fputype) { case FPSR_SYSID_FPPC: printf("FPPC/WE32206"); #ifdef FPU_FPPC /* XXX Uncomment when we have minimal support. */ supported = 1; sc->sc_ctxload = fpctx_load_fppc; sc->sc_ctxsave = fpctx_save_fppc; sc->sc_enable = fpu_enable_fppc; sc->sc_disable = fpu_disable_fppc; #endif break; case FPSR_SYSID_FPA: printf("FPA"); #ifdef FPU_FPA /* XXX Uncomment when we have minimal support. */ supported = 1; sc->sc_ctxload = fpctx_load_fpa; sc->sc_ctxsave = fpctx_save_fpa; sc->sc_enable = fpu_enable_fpa; sc->sc_disable = fpu_disable_fpa; #endif break; default: printf("Unknown type, ID=0x%02x", sc->sc_fputype >> 24); break; } printf("\n"); if (!supported) printf("%s: WARNING: FPU type not supported by kernel\n", self->dv_xname); } static label_t undef_jmp; static int fpu_undef_handler(u_int addr, u_int insn, struct trapframe *tf, int fault_code) { longjmp(&undef_jmp); } static register_t fpu_identify() { volatile register_t fpsr; void *uh; if (setjmp(&undef_jmp) == 0) { uh = install_coproc_handler(FPA_COPROC, fpu_undef_handler); fpsr = 0; __asm volatile ("rfs %0" : "=r" (fpsr)); } remove_coproc_handler(uh); return fpsr & FPSR_SYSID_MASK; } void fpu_swapout(struct proc *p) { struct pcb *pcb; pcb = &p->p_addr->u_pcb; if (pcb->pcb_flags & PCB_OWNFPU) { the_fpu->sc_ctxsave(&pcb->pcb_ff); the_fpu->sc_disable(); the_fpu->sc_owner = NULL; pcb->pcb_flags &= ~PCB_OWNFPU; } }