From c7f81c9453375d6416658995eafd3397cb9bba1d Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 2 May 2007 19:27:20 +0200 Subject: [PATCH] i386: Verify important CPUID bits in real mode Check some CPUID bits that are needed for compiler generated early in boot. When the system is still in real mode before changing the VESA BIOS mode it is possible to still display an visible error message on the screen. Similar to x86-64. Includes cleanups from Eric Biederman Signed-off-by: Andi Kleen --- include/asm-i386/cpufeature.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/asm-i386/cpufeature.h') diff --git a/include/asm-i386/cpufeature.h b/include/asm-i386/cpufeature.h index d1b8e4ab6c1..e66d004aa65 100644 --- a/include/asm-i386/cpufeature.h +++ b/include/asm-i386/cpufeature.h @@ -7,7 +7,10 @@ #ifndef __ASM_I386_CPUFEATURE_H #define __ASM_I386_CPUFEATURE_H +#ifndef __ASSEMBLY__ #include +#endif +#include #define NCAPINTS 7 /* N 32-bit words worth of info */ -- cgit v1.2.3-70-g09d2 From 3671df8572a299acff9c9cac2bf7279ee614d154 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 2 May 2007 19:27:20 +0200 Subject: [PATCH] i386: Evaluate constant cpu features at runtime Redefine cpu_has() to evaluate cpu features already checked in early boot at compile time. This way the compiler might eliminate some dead code. Signed-off-by: Andi Kleen --- include/asm-i386/cpufeature.h | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'include/asm-i386/cpufeature.h') diff --git a/include/asm-i386/cpufeature.h b/include/asm-i386/cpufeature.h index e66d004aa65..20e849ae6dd 100644 --- a/include/asm-i386/cpufeature.h +++ b/include/asm-i386/cpufeature.h @@ -106,8 +106,12 @@ #define X86_FEATURE_LAHF_LM (6*32+ 0) /* LAHF/SAHF in long mode */ #define X86_FEATURE_CMP_LEGACY (6*32+ 1) /* If yes HyperThreading not valid */ -#define cpu_has(c, bit) test_bit(bit, (c)->x86_capability) -#define boot_cpu_has(bit) test_bit(bit, boot_cpu_data.x86_capability) +#define cpu_has(c, bit) \ + ((__builtin_constant_p(bit) && (bit) < 32 && \ + (1UL << (bit)) & REQUIRED_MASK1) ? \ + 1 : \ + test_bit(bit, (c)->x86_capability)) +#define boot_cpu_has(bit) cpu_has(&boot_cpu_data, bit) #define cpu_has_fpu boot_cpu_has(X86_FEATURE_FPU) #define cpu_has_vme boot_cpu_has(X86_FEATURE_VME) -- cgit v1.2.3-70-g09d2 From 3aefbe0746580a710d4392a884ac1e4aac7c728f Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 2 May 2007 19:27:20 +0200 Subject: [PATCH] i386: Implement X86_FEATURE_SYNC_RDTSC on i386 Syncs up with x86-64. Signed-off-by: Andi Kleen --- arch/i386/kernel/cpu/intel.c | 4 +++- include/asm-i386/cpufeature.h | 1 + include/asm-i386/tsc.h | 4 ---- 3 files changed, 4 insertions(+), 5 deletions(-) (limited to 'include/asm-i386/cpufeature.h') diff --git a/arch/i386/kernel/cpu/intel.c b/arch/i386/kernel/cpu/intel.c index 56fe2658495..dc4e08147b1 100644 --- a/arch/i386/kernel/cpu/intel.c +++ b/arch/i386/kernel/cpu/intel.c @@ -188,8 +188,10 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c) } #endif - if (c->x86 == 15) + if (c->x86 == 15) { set_bit(X86_FEATURE_P4, c->x86_capability); + set_bit(X86_FEATURE_SYNC_RDTSC, c->x86_capability); + } if (c->x86 == 6) set_bit(X86_FEATURE_P3, c->x86_capability); if ((c->x86 == 0xf && c->x86_model >= 0x03) || diff --git a/include/asm-i386/cpufeature.h b/include/asm-i386/cpufeature.h index 20e849ae6dd..b8a3a5a85fd 100644 --- a/include/asm-i386/cpufeature.h +++ b/include/asm-i386/cpufeature.h @@ -79,6 +79,7 @@ #define X86_FEATURE_PEBS (3*32+12) /* Precise-Event Based Sampling */ #define X86_FEATURE_BTS (3*32+13) /* Branch Trace Store */ #define X86_FEATURE_LAPIC_TIMER_BROKEN (3*32+ 14) /* lapic timer broken in C1 */ +#define X86_FEATURE_SYNC_RDTSC (3*32+15) /* RDTSC synchronizes the CPU */ /* Intel-defined CPU features, CPUID level 0x00000001 (ecx), word 4 */ #define X86_FEATURE_XMM3 (4*32+ 0) /* Streaming SIMD Extensions-3 */ diff --git a/include/asm-i386/tsc.h b/include/asm-i386/tsc.h index 346976632e1..0181f9df753 100644 --- a/include/asm-i386/tsc.h +++ b/include/asm-i386/tsc.h @@ -35,7 +35,6 @@ static inline cycles_t get_cycles(void) static __always_inline cycles_t get_cycles_sync(void) { unsigned long long ret; -#ifdef X86_FEATURE_SYNC_RDTSC unsigned eax; /* @@ -44,9 +43,6 @@ static __always_inline cycles_t get_cycles_sync(void) */ alternative_io("cpuid", ASM_NOP2, X86_FEATURE_SYNC_RDTSC, "=a" (eax), "0" (1) : "ebx","ecx","edx","memory"); -#else - sync_core(); -#endif rdtscll(ret); return ret; -- cgit v1.2.3-70-g09d2 From 9bccb23dc5fc2d268ab676e2d4212d29e230fd86 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 2 May 2007 19:27:20 +0200 Subject: [PATCH] i386: Add X86_FEATURE_RDTSCP Following x86-64 Signed-off-by: Andi Kleen --- include/asm-i386/cpufeature.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/asm-i386/cpufeature.h') diff --git a/include/asm-i386/cpufeature.h b/include/asm-i386/cpufeature.h index b8a3a5a85fd..f514e906643 100644 --- a/include/asm-i386/cpufeature.h +++ b/include/asm-i386/cpufeature.h @@ -52,6 +52,7 @@ #define X86_FEATURE_MP (1*32+19) /* MP Capable. */ #define X86_FEATURE_NX (1*32+20) /* Execute Disable */ #define X86_FEATURE_MMXEXT (1*32+22) /* AMD MMX extensions */ +#define X86_FEATURE_RDTSCP (1*32+27) /* RDTSCP */ #define X86_FEATURE_LM (1*32+29) /* Long Mode (x86-64) */ #define X86_FEATURE_3DNOWEXT (1*32+30) /* AMD 3DNow! extensions */ #define X86_FEATURE_3DNOW (1*32+31) /* 3DNow! */ -- cgit v1.2.3-70-g09d2