[PATCH] i386: move SIMD initialization

[PATCH] i386: move SIMD initialization

[Jan Beulich]

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Move some code unrelated to any dealing with hardware bugs from i386's
bugs.h to a more logical place.

From: Jan Beulich <jbeulich@novell.com>

(actual patch attached)


[-- Attachment #2: linux-2.6.14-i386-fxsr.patch --]
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Move some code unrelated to any dealing with hardware bugs from i386's
bugs.h to a more logical place.

From: Jan Beulich <jbeulich@novell.com>

--- 2.6.14/arch/i386/kernel/traps.c	2005-10-28 02:02:08.000000000 +0200
+++ 2.6.14-i386-fxsr/arch/i386/kernel/traps.c	2005-11-04 17:00:47.000000000 +0100
@@ -1101,6 +1101,24 @@ void __init trap_init(void)
 #endif
 	set_trap_gate(19,&simd_coprocessor_error);
 
+	if (cpu_has_fxsr) {
+		/*
+		 * Verify that the FXSAVE/FXRSTOR data will be 16-byte aligned.
+		 */
+		struct fxsrAlignAssert {
+			int _:!(offsetof(struct task_struct, thread.i387.fxsave) & 15);
+		};
+
+		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_gate(SYSCALL_VECTOR,&system_call);
 
 	/*
--- 2.6.14/include/asm-i386/bugs.h	2005-10-28 02:02:08.000000000 +0200
+++ 2.6.14-i386-fxsr/include/asm-i386/bugs.h	2005-11-04 16:19:34.000000000 +0100
@@ -8,9 +8,6 @@
  *        <rreilova@ececs.uc.edu>
  *	- Channing Corn (tests & fixes),
  *	- Andrew D. Balsa (code cleanup).
- *
- *  Pentium III FXSR, SSE support
- *	Gareth Hughes <gareth@valinux.com>, May 2000
  */
 
 /*
@@ -76,25 +73,7 @@ static void __init check_fpu(void)
 		return;
 	}
 
-/* Enable FXSR and company _before_ testing for FP problems. */
-	/*
-	 * Verify that the FXSAVE/FXRSTOR data will be 16-byte aligned.
-	 */
-	if (offsetof(struct task_struct, thread.i387.fxsave) & 15) {
-		extern void __buggy_fxsr_alignment(void);
-		__buggy_fxsr_alignment();
-	}
-	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");
-	}
-
+/* trap_init() enabled FXSR and company _before_ testing for FP problems here. */
 	/* Test for the divl bug.. */
 	__asm__("fninit\n\t"
 		"fldl %1\n\t"