x86, fpu: Merge fpu_init()

Make fpu_init() handle 32-bit setup.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1283563039-3466-3-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

3 files changed, 14 insertions, 35 deletions

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 490dac63c2d2..f9e23e8639eb 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1264,13 +1264,6 @@ void __cpuinit cpu_init(void)
         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();
 }
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index 2605c50b11d3..82166519497a 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -85,7 +85,6 @@ static void __cpuinit init_thread_xstate(void)
 #endif
 }
 
-#ifdef CONFIG_X86_64
 /*
  * Called at bootup to set up the initial FPU state that is later cloned
  * into all processes.
@@ -93,12 +92,21 @@ static void __cpuinit init_thread_xstate(void)
 
 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();
@@ -109,16 +117,6 @@ void __cpuinit fpu_init(void)
         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
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 60788dee0f8a..d0029eb58589 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -881,18 +881,6 @@ void __init trap_init(void)
 #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