From 2e2f3da7714f323a0db65baa19b2b8110cc23f95 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Sun, 26 Apr 2015 14:40:54 +0200 Subject: [PATCH] x86/fpu: Factor out fpu__init_system_early_generic() 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 Cc: Andy Lutomirski Cc: Dave Hansen Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Ingo Molnar --- 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 @@ -64,6 +64,29 @@ void fpu__init_check_bugs(void) check_fpu(); } +/* + * 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: */ @@ -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() */ } -- 2.20.1