From: Fenghua Yu Date: Sat, 22 Oct 2016 13:19:54 +0000 (-0700) Subject: x86/intel_rdt: Add Haswell feature discovery X-Git-Tag: microblaze-4.13-rc1~982^2~26 X-Git-Url: http://git.monstr.eu/?a=commitdiff_plain;h=113c60970cf41723891e3a1b303517eaf8510bb5;p=linux-2.6-microblaze.git x86/intel_rdt: Add Haswell feature discovery Some Haswell generation CPUs support RDT, but they don't enumerate this via CPUID. Use rdmsr_safe() and wrmsr_safe() to probe the MSRs on cpu model 63 (INTEL_FAM6_HASWELL_X) Move the relevant defines into a common header file which is shared between RDT/CQM and RDT/Allocation to avoid duplication. Signed-off-by: Fenghua Yu Cc: "Ravi V Shankar" Cc: "Tony Luck" Cc: "David Carrillo-Cisneros" Cc: "Sai Prakhya" Cc: "Peter Zijlstra" Cc: "Stephane Eranian" Cc: "Dave Hansen" Cc: "Shaohua Li" Cc: "Nilay Vaish" Cc: "Vikas Shivappa" Cc: "Ingo Molnar" Cc: "Borislav Petkov" Cc: "H. Peter Anvin" Link: http://lkml.kernel.org/r/1477142405-32078-8-git-send-email-fenghua.yu@intel.com Signed-off-by: Thomas Gleixner --- diff --git a/arch/x86/events/intel/cqm.c b/arch/x86/events/intel/cqm.c index 8f82b02934fa..df868745ad2b 100644 --- a/arch/x86/events/intel/cqm.c +++ b/arch/x86/events/intel/cqm.c @@ -7,9 +7,9 @@ #include #include #include +#include #include "../perf_event.h" -#define MSR_IA32_PQR_ASSOC 0x0c8f #define MSR_IA32_QM_CTR 0x0c8e #define MSR_IA32_QM_EVTSEL 0x0c8d diff --git a/arch/x86/include/asm/intel_rdt.h b/arch/x86/include/asm/intel_rdt.h new file mode 100644 index 000000000000..3aca86ddfa43 --- /dev/null +++ b/arch/x86/include/asm/intel_rdt.h @@ -0,0 +1,6 @@ +#ifndef _ASM_X86_INTEL_RDT_H +#define _ASM_X86_INTEL_RDT_H + +#define IA32_L3_CBM_BASE 0xc90 + +#endif /* _ASM_X86_INTEL_RDT_H */ diff --git a/arch/x86/include/asm/intel_rdt_common.h b/arch/x86/include/asm/intel_rdt_common.h new file mode 100644 index 000000000000..e6e15cfd083f --- /dev/null +++ b/arch/x86/include/asm/intel_rdt_common.h @@ -0,0 +1,6 @@ +#ifndef _ASM_X86_INTEL_RDT_COMMON_H +#define _ASM_X86_INTEL_RDT_COMMON_H + +#define MSR_IA32_PQR_ASSOC 0x0c8f + +#endif /* _ASM_X86_INTEL_RDT_COMMON_H */ diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c index 7d7aebeaac76..f8e35cf28792 100644 --- a/arch/x86/kernel/cpu/intel_rdt.c +++ b/arch/x86/kernel/cpu/intel_rdt.c @@ -27,16 +27,57 @@ #include #include +#include +#include +#include + +/* + * cache_alloc_hsw_probe() - Have to probe for Intel haswell server CPUs + * as they do not have CPUID enumeration support for Cache allocation. + * The check for Vendor/Family/Model is not enough to guarantee that + * the MSRs won't #GP fault because only the following SKUs support + * CAT: + * Intel(R) Xeon(R) CPU E5-2658 v3 @ 2.20GHz + * Intel(R) Xeon(R) CPU E5-2648L v3 @ 1.80GHz + * Intel(R) Xeon(R) CPU E5-2628L v3 @ 2.00GHz + * Intel(R) Xeon(R) CPU E5-2618L v3 @ 2.30GHz + * Intel(R) Xeon(R) CPU E5-2608L v3 @ 2.00GHz + * Intel(R) Xeon(R) CPU E5-2658A v3 @ 2.20GHz + * + * Probe by trying to write the first of the L3 cach mask registers + * and checking that the bits stick. Max CLOSids is always 4 and max cbm length + * is always 20 on hsw server parts. The minimum cache bitmask length + * allowed for HSW server is always 2 bits. Hardcode all of them. + */ +static inline bool cache_alloc_hsw_probe(void) +{ + if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && + boot_cpu_data.x86 == 6 && + boot_cpu_data.x86_model == INTEL_FAM6_HASWELL_X) { + u32 l, h, max_cbm = BIT_MASK(20) - 1; + + if (wrmsr_safe(IA32_L3_CBM_BASE, max_cbm, 0)) + return false; + rdmsr(IA32_L3_CBM_BASE, l, h); + + /* If all the bits were set in MSR, return success */ + return l == max_cbm; + } + + return false; +} + static inline bool get_rdt_resources(void) { - bool ret = false; + if (cache_alloc_hsw_probe()) + return true; if (!boot_cpu_has(X86_FEATURE_RDT_A)) return false; - if (boot_cpu_has(X86_FEATURE_CAT_L3)) - ret = true; + if (!boot_cpu_has(X86_FEATURE_CAT_L3)) + return false; - return ret; + return true; } static int __init intel_rdt_late_init(void)