Commit 1bca1000 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'pm+acpi-4.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 

Pull power management and ACPI fixes from Rafael Wysocki:
 "These are fixes mostly, for a few changes made in this cycle (the
  intel_idle driver, the OPP library, the ACPI EC driver, turbostat) and
  for some issues that have just been discovered (ACPI PCI IRQ
  management, PCI power management documentation, turbostat), with a
  couple of cleanups on top of them.

  Specifics:

   - intel_idle driver fixup for the recently added Skylake chips
     support (Len Brown).

   - Operating Performance Points (OPP) library fix related to the
     recently added support for new DT bindings and a fix for a typo in
     a comment (Viresh Kumar, Stephen Boyd).

   - ACPI EC driver fix for a recently introduced memory leak in an
     error code path (Lv Zheng).

   - ACPI PCI IRQ management fix for the issue where an ISA IRQ is
     shared with a PCI device which requires it to be configured in a
     different way and may cause an interrupt storm to happen as a
     result with an extra ACPI SCI IRQ handling simplification on top of
     it (Jiang Liu).

   - Update of the PCI power management documentation that became
     outdated and started to actively confuse the readers to make it
     actually reflect the code (Rafael J Wysocki).

   - turbostat fixes including an IVB Xeon regression fix (related to
     the --debug command line option), Skylake adjustment for the TSC
     running at a frequency that doesn't match the base one exactly, and
     a Knights Landing quirk to account for the fact that it only
     updates APERF and MPERF every 1024 clock cycles plus bumping up the
     turbostat version number (Len Brown, Hubert Chrzaniuk)"

* tag 'pm+acpi-4.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  tools/power turbosat: update version number
  tools/power turbostat: SKL: Adjust for TSC difference from base frequency
  tools/power turbostat: KNL workaround for %Busy and Avg_MHz
  tools/power turbostat: IVB Xeon: fix --debug regression
  ACPI / PCI: Remove duplicated penalty on SCI IRQ
  ACPI, PCI, irq: Do not share PCI IRQ with ISA IRQ
  ACPI / EC: Fix a memory leak issue in acpi_ec_query()
  PM / OPP: Fix typo modifcation -> modification
  PCI / PM: Update runtime PM documentation for PCI devices
  PM / OPP: of_property_count_u32_elems() can return errors
  intel_idle: Skylake Client Support - updated
parents 3deaa4f5 eb6d1c28

Documentation/power/pci.txt

+38 −13
Original line number Diff line number Diff line
@@ -979,20 +979,45 @@ every time right after the runtime_resume() callback has returned 
(alternatively, the runtime_suspend() callback will have to check if the

device should really be suspended and return -EAGAIN if that is not the case).



The runtime PM of PCI devices is disabled by default.  It is also blocked by

pci_pm_init() that runs the pm_runtime_forbid() helper function.  If a PCI

driver implements the runtime PM callbacks and intends to use the runtime PM

framework provided by the PM core and the PCI subsystem, it should enable this

feature by executing the pm_runtime_enable() helper function.  However, the

driver should not call the pm_runtime_allow() helper function unblocking

the runtime PM of the device.  Instead, it should allow user space or some

platform-specific code to do that (user space can do it via sysfs), although

once it has called pm_runtime_enable(), it must be prepared to handle the

The runtime PM of PCI devices is enabled by default by the PCI core.  PCI

device drivers do not need to enable it and should not attempt to do so.

However, it is blocked by pci_pm_init() that runs the pm_runtime_forbid()

helper function.  In addition to that, the runtime PM usage counter of

each PCI device is incremented by local_pci_probe() before executing the

probe callback provided by the device's driver.



If a PCI driver implements the runtime PM callbacks and intends to use the

runtime PM framework provided by the PM core and the PCI subsystem, it needs

to decrement the device's runtime PM usage counter in its probe callback

function.  If it doesn't do that, the counter will always be different from

zero for the device and it will never be runtime-suspended.  The simplest

way to do that is by calling pm_runtime_put_noidle(), but if the driver

wants to schedule an autosuspend right away, for example, it may call

pm_runtime_put_autosuspend() instead for this purpose.  Generally, it

just needs to call a function that decrements the devices usage counter

from its probe routine to make runtime PM work for the device.



It is important to remember that the driver's runtime_suspend() callback

may be executed right after the usage counter has been decremented, because

user space may already have cuased the pm_runtime_allow() helper function

unblocking the runtime PM of the device to run via sysfs, so the driver must

be prepared to cope with that.



The driver itself should not call pm_runtime_allow(), though.  Instead, it

should let user space or some platform-specific code do that (user space can

do it via sysfs as stated above), but it must be prepared to handle the

runtime PM of the device correctly as soon as pm_runtime_allow() is called

(which may happen at any time).  [It also is possible that user space causes

pm_runtime_allow() to be called via sysfs before the driver is loaded, so in

fact the driver has to be prepared to handle the runtime PM of the device as

soon as it calls pm_runtime_enable().]

(which may happen at any time, even before the driver is loaded).



When the driver's remove callback runs, it has to balance the decrementation

of the device's runtime PM usage counter at the probe time.  For this reason,

if it has decremented the counter in its probe callback, it must run

pm_runtime_get_noresume() in its remove callback.  [Since the core carries

out a runtime resume of the device and bumps up the device's usage counter

before running the driver's remove callback, the runtime PM of the device

is effectively disabled for the duration of the remove execution and all

runtime PM helper functions incrementing the device's usage counter are

then effectively equivalent to pm_runtime_get_noresume().]



The runtime PM framework works by processing requests to suspend or resume

devices, or to check if they are idle (in which cases it is reasonable to

drivers/acpi/ec.c

+2 −0
Original line number Diff line number Diff line
@@ -1044,8 +1044,10 @@ static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 
		goto err_exit;



	mutex_lock(&ec->mutex);

	result = -ENODATA;

	list_for_each_entry(handler, &ec->list, node) {

		if (value == handler->query_bit) {

			result = 0;

			q->handler = acpi_ec_get_query_handler(handler);

			ec_dbg_evt("Query(0x%02x) scheduled",

				   q->handler->query_bit);

drivers/acpi/pci_irq.c

+1 −0
Original line number Diff line number Diff line
@@ -372,6 +372,7 @@ static int acpi_isa_register_gsi(struct pci_dev *dev) 


	/* Interrupt Line values above 0xF are forbidden */

	if (dev->irq > 0 && (dev->irq <= 0xF) &&

	    acpi_isa_irq_available(dev->irq) &&

	    (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) {

		dev_warn(&dev->dev, "PCI INT %c: no GSI - using ISA IRQ %d\n",

			 pin_name(dev->pin), dev->irq);

drivers/acpi/pci_link.c

+14 −2
Original line number Diff line number Diff line
@@ -498,8 +498,7 @@ int __init acpi_irq_penalty_init(void) 
			    PIRQ_PENALTY_PCI_POSSIBLE;

		}

	}

	/* Add a penalty for the SCI */

	acpi_irq_penalty[acpi_gbl_FADT.sci_interrupt] += PIRQ_PENALTY_PCI_USING;



	return 0;

}
@@ -553,6 +552,13 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link) 
				irq = link->irq.possible[i];

		}

	}

	if (acpi_irq_penalty[irq] >= PIRQ_PENALTY_ISA_ALWAYS) {

		printk(KERN_ERR PREFIX "No IRQ available for %s [%s]. "

			    "Try pci=noacpi or acpi=off\n",

			    acpi_device_name(link->device),

			    acpi_device_bid(link->device));

		return -ENODEV;

	}



	/* Attempt to enable the link device at this IRQ. */

	if (acpi_pci_link_set(link, irq)) {
@@ -821,6 +827,12 @@ void acpi_penalize_isa_irq(int irq, int active) 
	}

}



bool acpi_isa_irq_available(int irq)

{

	return irq >= 0 && (irq >= ARRAY_SIZE(acpi_irq_penalty) ||

			    acpi_irq_penalty[irq] < PIRQ_PENALTY_ISA_ALWAYS);

}



/*

 * Penalize IRQ used by ACPI SCI. If ACPI SCI pin attributes conflict with

 * PCI IRQ attributes, mark ACPI SCI as ISA_ALWAYS so it won't be use for

drivers/base/power/opp.c

+12 −5
Original line number Diff line number Diff line
@@ -892,10 +892,17 @@ static int opp_get_microvolt(struct dev_pm_opp *opp, struct device *dev) 
	u32 microvolt[3] = {0};

	int count, ret;



	count = of_property_count_u32_elems(opp->np, "opp-microvolt");

	if (!count)

	/* Missing property isn't a problem, but an invalid entry is */

	if (!of_find_property(opp->np, "opp-microvolt", NULL))

		return 0;



	count = of_property_count_u32_elems(opp->np, "opp-microvolt");

	if (count < 0) {

		dev_err(dev, "%s: Invalid opp-microvolt property (%d)\n",

			__func__, count);

		return count;

	}



	/* There can be one or three elements here */

	if (count != 1 && count != 3) {

		dev_err(dev, "%s: Invalid number of elements in opp-microvolt property (%d)\n",
@@ -1063,7 +1070,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_add); 
 * share a common logic which is isolated here.

 *

 * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the

 * copy operation, returns 0 if no modifcation was done OR modification was

 * copy operation, returns 0 if no modification was done OR modification was

 * successful.

 *

 * Locking: The internal device_opp and opp structures are RCU protected.
@@ -1151,7 +1158,7 @@ unlock: 
 * mutex locking or synchronize_rcu() blocking calls cannot be used.

 *

 * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the

 * copy operation, returns 0 if no modifcation was done OR modification was

 * copy operation, returns 0 if no modification was done OR modification was

 * successful.

 */

int dev_pm_opp_enable(struct device *dev, unsigned long freq)
@@ -1177,7 +1184,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_enable); 
 * mutex locking or synchronize_rcu() blocking calls cannot be used.

 *

 * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the

 * copy operation, returns 0 if no modifcation was done OR modification was

 * copy operation, returns 0 if no modification was done OR modification was

 * successful.

 */

int dev_pm_opp_disable(struct device *dev, unsigned long freq)

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