From 7c5314b88da6d5af98239786772a1c44cc5eb67d Mon Sep 17 00:00:00 2001 From: Kan Liang Date: Wed, 8 Aug 2018 00:12:08 -0700 Subject: perf/x86/intel: Add quirk for Goldmont Plus A ucode patch is needed for Goldmont Plus while counter freezing feature is enabled. Otherwise, there will be some issues, e.g. PMI flood with some events. Add a quirk to check microcode version. If the system starts with the wrong ucode, leave the counter-freezing feature permanently disabled. Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: acme@kernel.org Link: http://lkml.kernel.org/r/1533712328-2834-3-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar --- arch/x86/events/intel/core.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index f17cf6c3ec6f..ab01ef9ddd77 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -3839,6 +3839,40 @@ static __init void intel_nehalem_quirk(void) } } +static bool intel_glp_counter_freezing_broken(int cpu) +{ + u32 rev = UINT_MAX; /* default to broken for unknown stepping */ + + switch (cpu_data(cpu).x86_stepping) { + case 1: + rev = 0x28; + break; + case 8: + rev = 0x6; + break; + } + + return (cpu_data(cpu).microcode < rev); +} + +static __init void intel_glp_counter_freezing_quirk(void) +{ + /* Check if it's already disabled */ + if (disable_counter_freezing) + return; + + /* + * If the system starts with the wrong ucode, leave the + * counter-freezing feature permanently disabled. + */ + if (intel_glp_counter_freezing_broken(raw_smp_processor_id())) { + pr_info("PMU counter freezing disabled due to CPU errata," + "please upgrade microcode\n"); + x86_pmu.counter_freezing = false; + x86_pmu.handle_irq = intel_pmu_handle_irq; + } +} + /* * enable software workaround for errata: * SNB: BJ122 @@ -4188,6 +4222,7 @@ __init int intel_pmu_init(void) break; case INTEL_FAM6_ATOM_GOLDMONT_PLUS: + x86_add_quirk(intel_glp_counter_freezing_quirk); memcpy(hw_cache_event_ids, glp_hw_cache_event_ids, sizeof(hw_cache_event_ids)); memcpy(hw_cache_extra_regs, glp_hw_cache_extra_regs, -- cgit v1.2.3-70-g09d2