/* * Copyright (c) 2005 Jakub Vana * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - 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. * - 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. */ /** @addtogroup ia32 * @{ */ /** @file * */ #include #include #include typedef void (*fpu_context_function)(fpu_context_t *fctx); static fpu_context_function fpu_save, fpu_restore; static void fpu_context_f_save(fpu_context_t *fctx) { asm volatile ( "fnsave %0" : "=m"(*fctx) ); } static void fpu_context_f_restore(fpu_context_t *fctx) { asm volatile ( "frstor %0" : "=m"(*fctx) ); } static void fpu_context_fx_save(fpu_context_t *fctx) { asm volatile ( "fxsave %0" : "=m"(*fctx) ); } static void fpu_context_fx_restore(fpu_context_t *fctx) { asm volatile ( "fxrstor %0" : "=m"(*fctx) ); } /* Setup using fxsr instruction */ void fpu_fxsr(void) { fpu_save=fpu_context_fx_save; fpu_restore=fpu_context_fx_restore; } /* Setup using not fxsr instruction */ void fpu_fsr(void) { fpu_save = fpu_context_f_save; fpu_restore = fpu_context_f_restore; } void fpu_context_save(fpu_context_t *fctx) { fpu_save(fctx); } void fpu_context_restore(fpu_context_t *fctx) { fpu_restore(fctx); } void fpu_init() { uint32_t help0 = 0, help1 = 0; asm volatile ( "fninit;\n" "stmxcsr %0\n" "mov %0,%1;\n" "or %2,%1;\n" "mov %1,%0;\n" "ldmxcsr %0;\n" : "+m" (help0), "+r" (help1) : "i" (0x1f80) ); } /** @} */