+++ /dev/null
-/*
- * linux/arch/x86_64/kernel/i387.c
- *
- * Copyright (C) 1994 Linus Torvalds
- * Copyright (C) 2002 Andi Kleen, SuSE Labs
- *
- * Pentium III FXSR, SSE support
- * General FPU state handling cleanups
- * Gareth Hughes <gareth@valinux.com>, May 2000
- *
- * x86-64 rework 2002 Andi Kleen.
- * Does direct fxsave in and out of user space now for signal handlers.
- * All the FSAVE<->FXSAVE conversion code has been moved to the 32bit emulation,
- * the 64bit user space sees a FXSAVE frame directly.
- */
-
-#include <lwk/task.h>
-#include <lwk/init.h>
-#include <arch/processor.h>
-#include <arch/i387.h>
-#include <arch/sigcontext.h>
-#include <arch/user.h>
-#include <arch/ptrace.h>
-#include <arch/uaccess.h>
-
-unsigned int mxcsr_feature_mask __read_mostly = 0xffffffff;
-
-void mxcsr_feature_mask_init(void)
-{
- unsigned int mask;
- clts();
- memset(¤t->arch.thread.i387.fxsave, 0, sizeof(struct i387_fxsave_struct));
- asm volatile("fxsave %0" : : "m" (current->arch.thread.i387.fxsave));
- mask = current->arch.thread.i387.fxsave.mxcsr_mask;
- if (mask == 0) mask = 0x0000ffbf;
- mxcsr_feature_mask &= mask;
- stts();
-}
-
-/*
- * Called at bootup to set up the initial FPU state that is later cloned
- * into all processes.
- */
-void __cpuinit fpu_init(void)
-{
- unsigned long oldcr0 = read_cr0();
- extern void __bad_fxsave_alignment(void);
-
- if (offsetof(struct task_struct, arch.thread.i387.fxsave) & 15)
- __bad_fxsave_alignment();
- set_in_cr4(X86_CR4_OSFXSR); /* enable fast FPU state save/restore */
- set_in_cr4(X86_CR4_OSXMMEXCPT); /* enable unmasked SSE exceptions */
-
- write_cr0(oldcr0 & ~((1UL<<3)|(1UL<<2))); /* clear TS and EM */
-
- mxcsr_feature_mask_init();
- /* clean state in init */
- current->arch.flags = 0;
- clear_used_math();
-}
-