clear_all_debug_regs();
dbg_restore_debug_regs();
- /*
- * Force FPU initialization:
- */
- current_thread_info()->status = 0;
- clear_used_math();
- mxcsr_feature_mask_init();
-
fpu_init();
xsave_init();
}
#endif
}
-#ifdef CONFIG_X86_64
/*
* 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();
-
- set_in_cr4(X86_CR4_OSFXSR);
- set_in_cr4(X86_CR4_OSXMMEXCPT);
+ unsigned long cr0;
+ unsigned long cr4_mask = 0;
- write_cr0(oldcr0 & ~(X86_CR0_TS|X86_CR0_EM)); /* clear TS and EM */
+ if (cpu_has_fxsr)
+ cr4_mask |= X86_CR4_OSFXSR;
+ if (cpu_has_xmm)
+ cr4_mask |= X86_CR4_OSXMMEXCPT;
+ if (cr4_mask)
+ set_in_cr4(cr4_mask);
+
+ cr0 = read_cr0();
+ cr0 &= ~(X86_CR0_TS|X86_CR0_EM); /* clear TS and EM */
+ if (!HAVE_HWFP)
+ cr0 |= X86_CR0_EM;
+ write_cr0(cr0);
if (!smp_processor_id())
init_thread_xstate();
clear_used_math();
}
-#else /* CONFIG_X86_64 */
-
-void __cpuinit fpu_init(void)
-{
- if (!smp_processor_id())
- init_thread_xstate();
-}
-
-#endif /* CONFIG_X86_32 */
-
void fpu_finit(struct fpu *fpu)
{
#ifdef CONFIG_X86_32
#endif
#ifdef CONFIG_X86_32
- if (cpu_has_fxsr) {
- printk(KERN_INFO "Enabling fast FPU save and restore... ");
- set_in_cr4(X86_CR4_OSFXSR);
- printk("done.\n");
- }
- if (cpu_has_xmm) {
- printk(KERN_INFO
- "Enabling unmasked SIMD FPU exception support... ");
- set_in_cr4(X86_CR4_OSXMMEXCPT);
- printk("done.\n");
- }
-
set_system_trap_gate(SYSCALL_VECTOR, &system_call);
set_bit(SYSCALL_VECTOR, used_vectors);
#endif