From 69cefc273f942bd7bb347a02e8b5b738d5f6e6f3 Mon Sep 17 00:00:00 2001
From: Lukasz Anaczkowski <lukasz.anaczkowski@intel.com>
Date: Tue, 21 Jul 2015 10:41:13 +0200
Subject: [PATCH 1/3] intel_pstate: Add get_scaling cpu_defaults param to
Knights Landing
Scaling for Knights Landing is same as the default scaling (100000).
When Knigts Landing support was added to the pstate driver, this
parameter was omitted resulting in a kernel panic during boot.
Fixes: b34ef932d79a (intel_pstate: Knights Landing support)
Reported-by: Yasuaki Ishimatsu <yishimat@redhat.com>
Signed-off-by: Dasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: Lukasz Anaczkowski <lukasz.anaczkowski@intel.com>
Acked-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Cc: 4.1+ <stable@vger.kernel.org> # 4.1+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/cpufreq/intel_pstate.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 15ada47bb720b..fcb929ec5304a 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -681,6 +681,7 @@ static struct cpu_defaults knl_params = {
.get_max = core_get_max_pstate,
.get_min = core_get_min_pstate,
.get_turbo = knl_get_turbo_pstate,
+ .get_scaling = core_get_scaling,
.set = core_set_pstate,
},
};
From 71b65445f0ed04c2afe3660f829779fddb2890c1 Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Tue, 28 Jul 2015 13:51:21 +0300
Subject: [PATCH 2/3] ACPI / PM: Use target_state to set the device power state
Commit 20dacb71ad28 ("ACPI / PM: Rework device power management to follow
ACPI 6") changed the device power management to use D3hot if the device
in question does not have _PR3 method even if D3cold was requested by the
caller.
However, if the device has _PR3 device->power.state is also set to D3hot
instead of D3Cold after power resources have been turned off because
device->power.state will be assigned from "state" instead of
"target_state".
Next time the device is transitioned to D0, acpi_power_transition() will
find that the current power state of the device is D3hot instead of D3cold
which causes it to power down all resources required for the current
(wrong) state D3hot.
Below is a simplified ASL example of a real touch panel device which
triggers the problem:
Scope (TPL1)
{
Name (_PR0, Package (1) { \_SB.PCI0.I2C1.PXTC })
Name (_PR3, Package (1) { \_SB.PCI0.I2C1.PXTC })
...
}
In both D0 and D3hot the same power resource is required. However, when
acpi_power_transition() turns off power resources required for D3hot (as
the device is transitioned to D0) it powers down PXTC which then makes the
device to lose its power.
Fix this by assigning "target_state" to the device power state instead of
"state" that is always D3hot even for devices with valid _PR3.
Fixes: 20dacb71ad28 (ACPI / PM: Rework device power management to follow ACPI 6)
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/acpi/device_pm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index 717afcdb5f4a9..88dbbb115285a 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -231,7 +231,7 @@ int acpi_device_set_power(struct acpi_device *device, int state)
dev_warn(&device->dev, "Failed to change power state to %s\n",
acpi_power_state_string(state));
} else {
- device->power.state = state;
+ device->power.state = target_state;
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Device [%s] transitioned to %s\n",
device->pnp.bus_id,
From 559ed40752dc63e68f9b9ad301b20e6a3fe5cf21 Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Date: Sun, 26 Jul 2015 02:07:47 +0200
Subject: [PATCH 3/3] cpufreq: Avoid attempts to create duplicate symbolic
links
After commit 87549141d516 (cpufreq: Stop migrating sysfs files on
hotplug) there is a problem with CPUs that share cpufreq policy
objects with other CPUs and are initially offline.
Say CPU1 shares a policy with CPU0 which is online and is registered
first. As part of the registration process, cpufreq_add_dev() is
called for it. It creates the policy object and a symbolic link
to it from the CPU1's sysfs directory. If CPU1 is registered
subsequently and it is offline at that time, cpufreq_add_dev() will
attempt to create a symbolic link to the policy object for it, but
that link is present already, so a warning about that will be
triggered.
To avoid that warning, make cpufreq use an additional CPU mask
containing related CPUs that are actually present for each policy
object. That mask is initialized when the policy object is populated
after its creation (for the first online CPU using it) and it includes
CPUs from the "policy CPUs" mask returned by the cpufreq driver's
->init() callback that are physically present at that time. Symbolic
links to the policy are created only for the CPUs in that mask.
If cpufreq_add_dev() is invoked for an offline CPU, it checks the
new mask and only creates the symlink if the CPU was not in it (the
CPU is added to the mask at the same time).
In turn, cpufreq_remove_dev() drops the given CPU from the new mask,
removes its symlink to the policy object and returns, unless it is
the CPU owning the policy object. In that case, the policy object
is moved to a new CPU's sysfs directory or deleted if the CPU being
removed was the last user of the policy.
While at it, notice that cpufreq_remove_dev() can't fail, because
its return value is ignored, so make it ignore return values from
__cpufreq_remove_dev_prepare() and __cpufreq_remove_dev_finish()
and prevent these functions from aborting on errors returned by
__cpufreq_governor(). Also drop the now unused sif argument from
them.
Fixes: 87549141d516 (cpufreq: Stop migrating sysfs files on hotplug)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reported-and-tested-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
---
drivers/cpufreq/cpufreq.c | 108 +++++++++++++++++++-------------------
include/linux/cpufreq.h | 1 +
2 files changed, 56 insertions(+), 53 deletions(-)
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 26063afb3eba4..7a3c30c4336f3 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1002,7 +1002,7 @@ static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy)
int ret = 0;
/* Some related CPUs might not be present (physically hotplugged) */
- for_each_cpu_and(j, policy->related_cpus, cpu_present_mask) {
+ for_each_cpu(j, policy->real_cpus) {
if (j == policy->kobj_cpu)
continue;
@@ -1019,7 +1019,7 @@ static void cpufreq_remove_dev_symlink(struct cpufreq_policy *policy)
unsigned int j;
/* Some related CPUs might not be present (physically hotplugged) */
- for_each_cpu_and(j, policy->related_cpus, cpu_present_mask) {
+ for_each_cpu(j, policy->real_cpus) {
if (j == policy->kobj_cpu)
continue;
@@ -1163,11 +1163,14 @@ static struct cpufreq_policy *cpufreq_policy_alloc(struct device *dev)
if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL))
goto err_free_cpumask;
+ if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL))
+ goto err_free_rcpumask;
+
ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, &dev->kobj,
"cpufreq");
if (ret) {
pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret);
- goto err_free_rcpumask;
+ goto err_free_real_cpus;
}
INIT_LIST_HEAD(&policy->policy_list);
@@ -1184,6 +1187,8 @@ static struct cpufreq_policy *cpufreq_policy_alloc(struct device *dev)
return policy;
+err_free_real_cpus:
+ free_cpumask_var(policy->real_cpus);
err_free_rcpumask:
free_cpumask_var(policy->related_cpus);
err_free_cpumask:
@@ -1234,6 +1239,7 @@ static void cpufreq_policy_free(struct cpufreq_policy *policy, bool notify)
write_unlock_irqrestore(&cpufreq_driver_lock, flags);
cpufreq_policy_put_kobj(policy, notify);
+ free_cpumask_var(policy->real_cpus);
free_cpumask_var(policy->related_cpus);
free_cpumask_var(policy->cpus);
kfree(policy);
@@ -1258,14 +1264,17 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
pr_debug("adding CPU %u\n", cpu);
- /*
- * Only possible if 'cpu' wasn't physically present earlier and we are
- * here from subsys_interface add callback. A hotplug notifier will
- * follow and we will handle it like logical CPU hotplug then. For now,
- * just create the sysfs link.
- */
- if (cpu_is_offline(cpu))
- return add_cpu_dev_symlink(per_cpu(cpufreq_cpu_data, cpu), cpu);
+ if (cpu_is_offline(cpu)) {
+ /*
+ * Only possible if we are here from the subsys_interface add
+ * callback. A hotplug notifier will follow and we will handle
+ * it as CPU online then. For now, just create the sysfs link,
+ * unless there is no policy or the link is already present.
+ */
+ policy = per_cpu(cpufreq_cpu_data, cpu);
+ return policy && !cpumask_test_and_set_cpu(cpu, policy->real_cpus)
+ ? add_cpu_dev_symlink(policy, cpu) : 0;
+ }
if (!down_read_trylock(&cpufreq_rwsem))
return 0;
@@ -1307,6 +1316,10 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
/* related cpus should atleast have policy->cpus */
cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus);
+ /* Remember which CPUs have been present at the policy creation time. */
+ if (!recover_policy)
+ cpumask_and(policy->real_cpus, policy->cpus, cpu_present_mask);
+
/*
* affected cpus must always be the one, which are online. We aren't
* managing offline cpus here.
@@ -1420,8 +1433,7 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
return ret;
}
-static int __cpufreq_remove_dev_prepare(struct device *dev,
- struct subsys_interface *sif)
+static int __cpufreq_remove_dev_prepare(struct device *dev)
{
unsigned int cpu = dev->id;
int ret = 0;
@@ -1437,10 +1449,8 @@ static int __cpufreq_remove_dev_prepare(struct device *dev,
if (has_target()) {
ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP);
- if (ret) {
+ if (ret)
pr_err("%s: Failed to stop governor\n", __func__);
- return ret;
- }
}
down_write(&policy->rwsem);
@@ -1473,8 +1483,7 @@ static int __cpufreq_remove_dev_prepare(struct device *dev,
return ret;
}
-static int __cpufreq_remove_dev_finish(struct device *dev,
- struct subsys_interface *sif)
+static int __cpufreq_remove_dev_finish(struct device *dev)
{
unsigned int cpu = dev->id;
int ret;
@@ -1492,10 +1501,8 @@ static int __cpufreq_remove_dev_finish(struct device *dev,
/* If cpu is last user of policy, free policy */
if (has_target()) {
ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
- if (ret) {
+ if (ret)
pr_err("%s: Failed to exit governor\n", __func__);
- return ret;
- }
}
/*
@@ -1506,10 +1513,6 @@ static int __cpufreq_remove_dev_finish(struct device *dev,
if (cpufreq_driver->exit)
cpufreq_driver->exit(policy);
- /* Free the policy only if the driver is getting removed. */
- if (sif)
- cpufreq_policy_free(policy, true);
-
return 0;
}
@@ -1521,42 +1524,41 @@ static int __cpufreq_remove_dev_finish(struct device *dev,
static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
{
unsigned int cpu = dev->id;
- int ret;
-
- /*
- * Only possible if 'cpu' is getting physically removed now. A hotplug
- * notifier should have already been called and we just need to remove
- * link or free policy here.
- */
- if (cpu_is_offline(cpu)) {
- struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
- struct cpumask mask;
+ struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
- if (!policy)
- return 0;
+ if (!policy)
+ return 0;
- cpumask_copy(&mask, policy->related_cpus);
- cpumask_clear_cpu(cpu, &mask);
+ if (cpu_online(cpu)) {
+ __cpufreq_remove_dev_prepare(dev);
+ __cpufreq_remove_dev_finish(dev);
+ }
- /*
- * Free policy only if all policy->related_cpus are removed
- * physically.
- */
- if (cpumask_intersects(&mask, cpu_present_mask)) {
- remove_cpu_dev_symlink(policy, cpu);
- return 0;
- }
+ cpumask_clear_cpu(cpu, policy->real_cpus);
+ if (cpumask_empty(policy->real_cpus)) {
cpufreq_policy_free(policy, true);
return 0;
}
- ret = __cpufreq_remove_dev_prepare(dev, sif);
+ if (cpu != policy->kobj_cpu) {
+ remove_cpu_dev_symlink(policy, cpu);
+ } else {
+ /*
+ * The CPU owning the policy object is going away. Move it to
+ * another suitable CPU.
+ */
+ unsigned int new_cpu = cpumask_first(policy->real_cpus);
+ struct device *new_dev = get_cpu_device(new_cpu);
+
+ dev_dbg(dev, "%s: Moving policy object to CPU%u\n", __func__, new_cpu);
- if (!ret)
- ret = __cpufreq_remove_dev_finish(dev, sif);
+ sysfs_remove_link(&new_dev->kobj, "cpufreq");
+ policy->kobj_cpu = new_cpu;
+ WARN_ON(kobject_move(&policy->kobj, &new_dev->kobj));
+ }
- return ret;
+ return 0;
}
static void handle_update(struct work_struct *work)
@@ -2395,11 +2397,11 @@ static int cpufreq_cpu_callback(struct notifier_block *nfb,
break;
case CPU_DOWN_PREPARE:
- __cpufreq_remove_dev_prepare(dev, NULL);
+ __cpufreq_remove_dev_prepare(dev);
break;
case CPU_POST_DEAD:
- __cpufreq_remove_dev_finish(dev, NULL);
+ __cpufreq_remove_dev_finish(dev);
break;
case CPU_DOWN_FAILED:
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 29ad97c34fd5c..bde1e567b3a93 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -62,6 +62,7 @@ struct cpufreq_policy {
/* CPUs sharing clock, require sw coordination */
cpumask_var_t cpus; /* Online CPUs only */
cpumask_var_t related_cpus; /* Online + Offline CPUs */
+ cpumask_var_t real_cpus; /* Related and present */
unsigned int shared_type; /* ACPI: ANY or ALL affected CPUs
should set cpufreq */