[PATCH V2 00/10] cpufreq: Migrate users of policy notifiers to QoS requests

[PATCH V2 00/10] cpufreq: Migrate users of policy notifiers to QoS requests

[Viresh Kumar]

Hello,

Now that cpufreq core supports taking QoS requests for min/max cpu
frequencies, lets migrate rest of the users to using them instead of the
policy notifiers.

The CPUFREQ_NOTIFY and CPUFREQ_ADJUST events of the policy notifiers are
removed as a result, but we have to add CPUFREQ_CREATE_POLICY and
CPUFREQ_REMOVE_POLICY events to it for the acpi stuff specifically,
though they are also used by arch_topology stuff now. So the policy
notifiers aren't completely removed.

Boot tested on my x86 PC and ARM hikey board.

This has already gone through build bot for a few days now.

V1->V2:
- Added Acked-by tags
- Reordered to keep cleanups at the bottom
- Rebased over 5.3-rc1

--
viresh

Viresh Kumar (10):
  cpufreq: Add policy create/remove notifiers
  thermal: cpu_cooling: Switch to QoS requests instead of cpufreq
    notifier
  powerpc: macintosh: Switch to QoS requests instead of cpufreq notifier
  cpufreq: powerpc_cbe: Switch to QoS requests instead of cpufreq
    notifier
  ACPI: cpufreq: Switch to QoS requests instead of cpufreq notifier
  arch_topology: Use CPUFREQ_CREATE_POLICY instead of CPUFREQ_NOTIFY
  video: sa1100fb: Remove cpufreq policy notifier
  video: pxafb: Remove cpufreq policy notifier
  cpufreq: Remove CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier
    events
  Documentation: cpufreq: Update policy notifier documentation

 Documentation/cpu-freq/core.txt            |  16 +--
 drivers/acpi/processor_driver.c            |  44 ++++++++-
 drivers/acpi/processor_perflib.c           | 106 +++++++++-----------
 drivers/acpi/processor_thermal.c           |  81 ++++++++-------
 drivers/base/arch_topology.c               |   2 +-
 drivers/cpufreq/cpufreq.c                  |  51 ++++------
 drivers/cpufreq/ppc_cbe_cpufreq.c          |  19 +++-
 drivers/cpufreq/ppc_cbe_cpufreq.h          |   8 ++
 drivers/cpufreq/ppc_cbe_cpufreq_pmi.c      |  96 +++++++++++-------
 drivers/macintosh/windfarm_cpufreq_clamp.c |  77 ++++++++++-----
 drivers/thermal/cpu_cooling.c              | 110 +++++----------------
 drivers/video/fbdev/pxafb.c                |  21 ----
 drivers/video/fbdev/pxafb.h                |   1 -
 drivers/video/fbdev/sa1100fb.c             |  27 -----
 drivers/video/fbdev/sa1100fb.h             |   1 -
 include/acpi/processor.h                   |  22 +++--
 include/linux/cpufreq.h                    |   4 +-
 17 files changed, 327 insertions(+), 359 deletions(-)

-- 
2.21.0.rc0.269.g1a574e7a288b

[PATCH V2 03/10] powerpc: macintosh: Switch to QoS requests instead of cpufreq notifier

[Viresh Kumar]

The cpufreq core now takes the min/max frequency constraints via QoS
requests and the CPUFREQ_ADJUST notifier shall get removed later on.

Switch over to using the QoS request for maximum frequency constraint
for windfarm_cpufreq_clamp driver.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/macintosh/windfarm_cpufreq_clamp.c | 77 ++++++++++++++--------
 1 file changed, 50 insertions(+), 27 deletions(-)

diff --git a/drivers/macintosh/windfarm_cpufreq_clamp.c b/drivers/macintosh/windfarm_cpufreq_clamp.c
index 52fd5fca89a0..705c6200814b 100644
--- a/drivers/macintosh/windfarm_cpufreq_clamp.c
+++ b/drivers/macintosh/windfarm_cpufreq_clamp.c
@@ -3,9 +3,11 @@
 #include <linux/errno.h>
 #include <linux/kernel.h>
 #include <linux/delay.h>
+#include <linux/pm_qos.h>
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/wait.h>
+#include <linux/cpu.h>
 #include <linux/cpufreq.h>
 
 #include <asm/prom.h>
@@ -16,36 +18,24 @@
 
 static int clamped;
 static struct wf_control *clamp_control;
-
-static int clamp_notifier_call(struct notifier_block *self,
-			       unsigned long event, void *data)
-{
-	struct cpufreq_policy *p = data;
-	unsigned long max_freq;
-
-	if (event != CPUFREQ_ADJUST)
-		return 0;
-
-	max_freq = clamped ? (p->cpuinfo.min_freq) : (p->cpuinfo.max_freq);
-	cpufreq_verify_within_limits(p, 0, max_freq);
-
-	return 0;
-}
-
-static struct notifier_block clamp_notifier = {
-	.notifier_call = clamp_notifier_call,
-};
+static struct dev_pm_qos_request qos_req;
+static unsigned int min_freq, max_freq;
 
 static int clamp_set(struct wf_control *ct, s32 value)
 {
-	if (value)
+	unsigned int freq;
+
+	if (value) {
+		freq = min_freq;
 		printk(KERN_INFO "windfarm: Clamping CPU frequency to "
 		       "minimum !\n");
-	else
+	} else {
+		freq = max_freq;
 		printk(KERN_INFO "windfarm: CPU frequency unclamped !\n");
+	}
 	clamped = value;
-	cpufreq_update_policy(0);
-	return 0;
+
+	return dev_pm_qos_update_request(&qos_req, freq);
 }
 
 static int clamp_get(struct wf_control *ct, s32 *value)
@@ -74,27 +64,60 @@ static const struct wf_control_ops clamp_ops = {
 
 static int __init wf_cpufreq_clamp_init(void)
 {
+	struct cpufreq_policy *policy;
 	struct wf_control *clamp;
+	struct device *dev;
+	int ret;
+
+	policy = cpufreq_cpu_get(0);
+	if (!policy) {
+		pr_warn("%s: cpufreq policy not found cpu0\n", __func__);
+		return -EPROBE_DEFER;
+	}
+
+	min_freq = policy->cpuinfo.min_freq;
+	max_freq = policy->cpuinfo.max_freq;
+	cpufreq_cpu_put(policy);
+
+	dev = get_cpu_device(0);
+	if (unlikely(!dev)) {
+		pr_warn("%s: No cpu device for cpu0\n", __func__);
+		return -ENODEV;
+	}
 
 	clamp = kmalloc(sizeof(struct wf_control), GFP_KERNEL);
 	if (clamp == NULL)
 		return -ENOMEM;
-	cpufreq_register_notifier(&clamp_notifier, CPUFREQ_POLICY_NOTIFIER);
+
+	ret = dev_pm_qos_add_request(dev, &qos_req, DEV_PM_QOS_MAX_FREQUENCY,
+				     max_freq);
+	if (ret < 0) {
+		pr_err("%s: Failed to add freq constraint (%d)\n", __func__,
+		       ret);
+		goto free;
+	}
+
 	clamp->ops = &clamp_ops;
 	clamp->name = "cpufreq-clamp";
-	if (wf_register_control(clamp))
+	ret = wf_register_control(clamp);
+	if (ret)
 		goto fail;
 	clamp_control = clamp;
 	return 0;
  fail:
+	dev_pm_qos_remove_request(&qos_req);
+
+ free:
 	kfree(clamp);
-	return -ENODEV;
+	return ret;
 }
 
 static void __exit wf_cpufreq_clamp_exit(void)
 {
-	if (clamp_control)
+	if (clamp_control) {
 		wf_unregister_control(clamp_control);
+		dev_pm_qos_remove_request(&qos_req);
+	}
 }
 
 
-- 
2.21.0.rc0.269.g1a574e7a288b