diff options
Diffstat (limited to 'arch/x86_64/kernel/setup.c')
| -rw-r--r-- | arch/x86_64/kernel/setup.c | 24 |
1 files changed, 16 insertions, 8 deletions
diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c index fc944b5e8f4a..af425a8049fb 100644 --- a/arch/x86_64/kernel/setup.c +++ b/arch/x86_64/kernel/setup.c @@ -471,8 +471,7 @@ void __init setup_arch(char **cmdline_p) if (LOADER_TYPE && INITRD_START) { if (INITRD_START + INITRD_SIZE <= (end_pfn << PAGE_SHIFT)) { reserve_bootmem_generic(INITRD_START, INITRD_SIZE); - initrd_start = - INITRD_START ? INITRD_START + PAGE_OFFSET : 0; + initrd_start = INITRD_START + PAGE_OFFSET; initrd_end = initrd_start+INITRD_SIZE; } else { @@ -732,11 +731,8 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c) /* Fix cpuid4 emulation for more */ num_cache_leaves = 3; - /* When there is only one core no need to synchronize RDTSC */ - if (num_possible_cpus() == 1) - set_bit(X86_FEATURE_SYNC_RDTSC, &c->x86_capability); - else - clear_bit(X86_FEATURE_SYNC_RDTSC, &c->x86_capability); + /* RDTSC can be speculated around */ + clear_bit(X86_FEATURE_SYNC_RDTSC, &c->x86_capability); } static void __cpuinit detect_ht(struct cpuinfo_x86 *c) @@ -835,6 +831,15 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c) set_bit(X86_FEATURE_ARCH_PERFMON, &c->x86_capability); } + if (cpu_has_ds) { + unsigned int l1, l2; + rdmsr(MSR_IA32_MISC_ENABLE, l1, l2); + if (!(l1 & (1<<11))) + set_bit(X86_FEATURE_BTS, c->x86_capability); + if (!(l1 & (1<<12))) + set_bit(X86_FEATURE_PEBS, c->x86_capability); + } + n = c->extended_cpuid_level; if (n >= 0x80000008) { unsigned eax = cpuid_eax(0x80000008); @@ -854,7 +859,10 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c) set_bit(X86_FEATURE_CONSTANT_TSC, &c->x86_capability); if (c->x86 == 6) set_bit(X86_FEATURE_REP_GOOD, &c->x86_capability); - set_bit(X86_FEATURE_SYNC_RDTSC, &c->x86_capability); + if (c->x86 == 15) + set_bit(X86_FEATURE_SYNC_RDTSC, &c->x86_capability); + else + clear_bit(X86_FEATURE_SYNC_RDTSC, &c->x86_capability); c->x86_max_cores = intel_num_cpu_cores(c); srat_detect_node(); |