[PATCH 119/208] x86/fpu: Factor out fpu__init_system_early_generic()

From: Ingo Molnar
Date: Tue May 05 2015 - 14:24:13 EST


Move the generic bits of fpu__detect() into fpu__init_system_early_generic().

We'll move some other code here too in a followup patch.

Reviewed-by: Borislav Petkov <bp@xxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/kernel/fpu/init.c | 41 ++++++++++++++++++++++++-----------------
1 file changed, 24 insertions(+), 17 deletions(-)

diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c
index c3f3a89cbbf6..3637c509956d 100644
--- a/arch/x86/kernel/fpu/init.c
+++ b/arch/x86/kernel/fpu/init.c
@@ -65,6 +65,29 @@ void fpu__init_check_bugs(void)
}

/*
+ * The earliest FPU detection code:
+ */
+static void fpu__init_system_early_generic(struct cpuinfo_x86 *c)
+{
+ unsigned long cr0;
+ u16 fsw, fcw;
+
+ fsw = fcw = 0xffff;
+
+ cr0 = read_cr0();
+ cr0 &= ~(X86_CR0_TS | X86_CR0_EM);
+ write_cr0(cr0);
+
+ asm volatile("fninit ; fnstsw %0 ; fnstcw %1"
+ : "+m" (fsw), "+m" (fcw));
+
+ if (fsw == 0 && (fcw & 0x103f) == 0x003f)
+ set_cpu_cap(c, X86_FEATURE_FPU);
+ else
+ clear_cpu_cap(c, X86_FEATURE_FPU);
+}
+
+/*
* Boot time FPU feature detection code:
*/
unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu;
@@ -269,23 +292,7 @@ __setup("no387", no_387);
*/
void fpu__detect(struct cpuinfo_x86 *c)
{
- unsigned long cr0;
- u16 fsw, fcw;
-
- fsw = fcw = 0xffff;
-
- cr0 = read_cr0();
- cr0 &= ~(X86_CR0_TS | X86_CR0_EM);
- write_cr0(cr0);
-
- asm volatile("fninit ; fnstsw %0 ; fnstcw %1"
- : "+m" (fsw), "+m" (fcw));
-
- if (fsw == 0 && (fcw & 0x103f) == 0x003f)
- set_cpu_cap(c, X86_FEATURE_FPU);
- else
- clear_cpu_cap(c, X86_FEATURE_FPU);
-
+ fpu__init_system_early_generic(c);
fpu__init_system();
/* The final cr0 value is set later, in fpu_init() */
}
--
2.1.0

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