[GIT PULL] x86/cpu changes for v4.3

From: Ingo Molnar
Date: Mon Aug 31 2015 - 13:45:59 EST


Linus,

Please pull the latest x86-cpu-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-cpu-for-linus

# HEAD: b1c599b8ff80ea79b9f8277a3f9f36a7b0cfedce x86/cpufeature: Add feature bit for Intel's Silicon Debug CPUID bit

Two changes: a suspend/resume quirk and a new CPUID bit definition.

Thanks,

Ingo

------------------>
Laura Abbott (1):
x86/cpu: Restore MSR_IA32_ENERGY_PERF_BIAS after resume

Mathias Krause (1):
x86/cpufeature: Add feature bit for Intel's Silicon Debug CPUID bit


arch/x86/include/asm/cpufeature.h | 1 +
arch/x86/kernel/cpu/common.c | 18 +++++++++++++++
arch/x86/kernel/cpu/cpu.h | 1 +
arch/x86/kernel/cpu/intel.c | 47 ++++++++++++++++++++++++++-------------
4 files changed, 52 insertions(+), 15 deletions(-)

diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index 3d6606fb97d0..4b11974b4ea7 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -119,6 +119,7 @@
#define X86_FEATURE_TM2 ( 4*32+ 8) /* Thermal Monitor 2 */
#define X86_FEATURE_SSSE3 ( 4*32+ 9) /* Supplemental SSE-3 */
#define X86_FEATURE_CID ( 4*32+10) /* Context ID */
+#define X86_FEATURE_SDBG ( 4*32+11) /* Silicon Debug */
#define X86_FEATURE_FMA ( 4*32+12) /* Fused multiply-add */
#define X86_FEATURE_CX16 ( 4*32+13) /* CMPXCHG16B */
#define X86_FEATURE_XTPR ( 4*32+14) /* Send Task Priority Messages */
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 922c5e0cea4c..fa95bb8829ce 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -13,6 +13,7 @@
#include <linux/kgdb.h>
#include <linux/smp.h>
#include <linux/io.h>
+#include <linux/syscore_ops.h>

#include <asm/stackprotector.h>
#include <asm/perf_event.h>
@@ -1488,3 +1489,20 @@ inline bool __static_cpu_has_safe(u16 bit)
return boot_cpu_has(bit);
}
EXPORT_SYMBOL_GPL(__static_cpu_has_safe);
+
+static void bsp_resume(void)
+{
+ if (this_cpu->c_bsp_resume)
+ this_cpu->c_bsp_resume(&boot_cpu_data);
+}
+
+static struct syscore_ops cpu_syscore_ops = {
+ .resume = bsp_resume,
+};
+
+static int __init init_cpu_syscore(void)
+{
+ register_syscore_ops(&cpu_syscore_ops);
+ return 0;
+}
+core_initcall(init_cpu_syscore);
diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h
index c37dc37e8317..2584265d4745 100644
--- a/arch/x86/kernel/cpu/cpu.h
+++ b/arch/x86/kernel/cpu/cpu.h
@@ -13,6 +13,7 @@ struct cpu_dev {
void (*c_init)(struct cpuinfo_x86 *);
void (*c_identify)(struct cpuinfo_x86 *);
void (*c_detect_tlb)(struct cpuinfo_x86 *);
+ void (*c_bsp_resume)(struct cpuinfo_x86 *);
int c_x86_vendor;
#ifdef CONFIG_X86_32
/* Optional vendor specific routine to obtain the cache size. */
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 50163fa9034f..98a13db5f4be 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -371,6 +371,36 @@ static void detect_vmx_virtcap(struct cpuinfo_x86 *c)
}
}

+static void init_intel_energy_perf(struct cpuinfo_x86 *c)
+{
+ u64 epb;
+
+ /*
+ * Initialize MSR_IA32_ENERGY_PERF_BIAS if not already initialized.
+ * (x86_energy_perf_policy(8) is available to change it at run-time.)
+ */
+ if (!cpu_has(c, X86_FEATURE_EPB))
+ return;
+
+ rdmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
+ if ((epb & 0xF) != ENERGY_PERF_BIAS_PERFORMANCE)
+ return;
+
+ pr_warn_once("ENERGY_PERF_BIAS: Set to 'normal', was 'performance'\n");
+ pr_warn_once("ENERGY_PERF_BIAS: View and update with x86_energy_perf_policy(8)\n");
+ epb = (epb & ~0xF) | ENERGY_PERF_BIAS_NORMAL;
+ wrmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
+}
+
+static void intel_bsp_resume(struct cpuinfo_x86 *c)
+{
+ /*
+ * MSR_IA32_ENERGY_PERF_BIAS is lost across suspend/resume,
+ * so reinitialize it properly like during bootup:
+ */
+ init_intel_energy_perf(c);
+}
+
static void init_intel(struct cpuinfo_x86 *c)
{
unsigned int l2 = 0;
@@ -478,21 +508,7 @@ static void init_intel(struct cpuinfo_x86 *c)
if (cpu_has(c, X86_FEATURE_VMX))
detect_vmx_virtcap(c);

- /*
- * Initialize MSR_IA32_ENERGY_PERF_BIAS if BIOS did not.
- * x86_energy_perf_policy(8) is available to change it at run-time
- */
- if (cpu_has(c, X86_FEATURE_EPB)) {
- u64 epb;
-
- rdmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
- if ((epb & 0xF) == ENERGY_PERF_BIAS_PERFORMANCE) {
- pr_warn_once("ENERGY_PERF_BIAS: Set to 'normal', was 'performance'\n");
- pr_warn_once("ENERGY_PERF_BIAS: View and update with x86_energy_perf_policy(8)\n");
- epb = (epb & ~0xF) | ENERGY_PERF_BIAS_NORMAL;
- wrmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
- }
- }
+ init_intel_energy_perf(c);
}

#ifdef CONFIG_X86_32
@@ -747,6 +763,7 @@ static const struct cpu_dev intel_cpu_dev = {
.c_detect_tlb = intel_detect_tlb,
.c_early_init = early_init_intel,
.c_init = init_intel,
+ .c_bsp_resume = intel_bsp_resume,
.c_x86_vendor = X86_VENDOR_INTEL,
};

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