lkml.org 
[lkml]   [2018]   [Oct]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:perf/core] perf/x86/intel: Add quirk for Goldmont Plus
Commit-ID:  7c5314b88da6d5af98239786772a1c44cc5eb67d
Gitweb: https://git.kernel.org/tip/7c5314b88da6d5af98239786772a1c44cc5eb67d
Author: Kan Liang <kan.liang@linux.intel.com>
AuthorDate: Wed, 8 Aug 2018 00:12:08 -0700
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Tue, 2 Oct 2018 10:14:33 +0200

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 <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
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 <mingo@kernel.org>
---
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,
\
 
 \ /
  Last update: 2018-10-02 12:11    [W:0.046 / U:9.840 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site