/*
* Copyright © 2012-2014 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
* Authors:
* Eugeni Dodonov <[email protected]>
* Daniel Vetter <[email protected]>
*
*/
#include <linux/pm_runtime.h>
#include <drm/drm_print.h>
#include "i915_drv.h"
#include "i915_trace.h"
/**
* DOC: runtime pm
*
* The i915 driver supports dynamic enabling and disabling of entire hardware
* blocks at runtime. This is especially important on the display side where
* software is supposed to control many power gates manually on recent hardware,
* since on the GT side a lot of the power management is done by the hardware.
* But even there some manual control at the device level is required.
*
* Since i915 supports a diverse set of platforms with a unified codebase and
* hardware engineers just love to shuffle functionality around between power
* domains there's a sizeable amount of indirection required. This file provides
* generic functions to the driver for grabbing and releasing references for
* abstract power domains. It then maps those to the actual power wells
* present for a given platform.
*/
static struct drm_i915_private *rpm_to_i915(struct intel_runtime_pm *rpm)
{
return container_of(rpm, struct drm_i915_private, runtime_pm);
}
#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM)
static void init_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm)
{
ref_tracker_dir_init(&rpm->debug, INTEL_REFTRACK_DEAD_COUNT, dev_name(rpm->kdev));
}
static intel_wakeref_t
track_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm)
{
if (!rpm->available || rpm->no_wakeref_tracking)
return -1;
return intel_ref_tracker_alloc(&rpm->debug);
}
static void untrack_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm,
intel_wakeref_t wakeref)
{
if (!rpm->available || rpm->no_wakeref_tracking)
return;
intel_ref_tracker_free(&rpm->debug, wakeref);
}
static void untrack_all_intel_runtime_pm_wakerefs(struct intel_runtime_pm *rpm)
{
ref_tracker_dir_exit(&rpm->debug);
}
static noinline void
__intel_wakeref_dec_and_check_tracking(struct intel_runtime_pm *rpm)
{
unsigned long flags;
if (!atomic_dec_and_lock_irqsave(&rpm->wakeref_count,
&rpm->debug.lock,
flags))
return;
ref_tracker_dir_print_locked(&rpm->debug, INTEL_REFTRACK_PRINT_LIMIT);
spin_unlock_irqrestore(&rpm->debug.lock, flags);
}
void print_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm,
struct drm_printer *p)
{
intel_ref_tracker_show(&rpm->debug, p);
}
#else
static void init_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm)
{
}
static intel_wakeref_t
track_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm)
{
return -1;
}
static void untrack_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm,
intel_wakeref_t wakeref)
{
}
static void
__intel_wakeref_dec_and_check_tracking(struct intel_runtime_pm *rpm)
{
atomic_dec(&rpm->wakeref_count);
}
static void
untrack_all_intel_runtime_pm_wakerefs(struct intel_runtime_pm *rpm)
{
}
#endif
static void
intel_runtime_pm_acquire(struct intel_runtime_pm *rpm, bool wakelock)
{
if (wakelock) {
atomic_add(1 + INTEL_RPM_WAKELOCK_BIAS, &rpm->wakeref_count);
assert_rpm_wakelock_held(rpm);
} else {
atomic_inc(&rpm->wakeref_count);
assert_rpm_raw_wakeref_held(rpm);
}
}
static void
intel_runtime_pm_release(struct intel_runtime_pm *rpm, int wakelock)
{
if (wakelock) {
assert_rpm_wakelock_held(rpm);
atomic_sub(INTEL_RPM_WAKELOCK_BIAS, &rpm->wakeref_count);
} else {
assert_rpm_raw_wakeref_held(rpm);
}
__intel_wakeref_dec_and_check_tracking(rpm);
}
static intel_wakeref_t __intel_runtime_pm_get(struct intel_runtime_pm *rpm,
bool wakelock)
{
struct drm_i915_private *i915 = rpm_to_i915(rpm);
int ret;
ret = pm_runtime_get_sync(rpm->kdev);
drm_WARN_ONCE(&i915->drm, ret < 0,
"pm_runtime_get_sync() failed: %d\n", ret);
intel_runtime_pm_acquire(rpm, wakelock);
return track_intel_runtime_pm_wakeref(rpm);
}
/**
* intel_runtime_pm_get_raw - grab a raw runtime pm reference
* @rpm: the intel_runtime_pm structure
*
* This is the unlocked version of intel_display_power_is_enabled() and should
* only be used from error capture and recovery code where deadlocks are
* possible.
* This function grabs a device-level runtime pm reference (mostly used for
* asynchronous PM management from display code) and ensures that it is powered
* up. Raw references are not considered during wakelock assert checks.
*
* Any runtime pm reference obtained by this function must have a symmetric
* call to intel_runtime_pm_put_raw() to release the reference again.
*
* Returns: the wakeref cookie to pass to intel_runtime_pm_put_raw(), evaluates
* as True if the wakeref was acquired, or False otherwise.
*/
intel_wakeref_t intel_runtime_pm_get_raw(struct intel_runtime_pm *rpm)
{
return __intel_runtime_pm_get(rpm, false);
}
/**
* intel_runtime_pm_get - grab a runtime pm reference
* @rpm: the intel_runtime_pm structure
*
* This function grabs a device-level runtime pm reference (mostly used for GEM
* code to ensure the GTT or GT is on) and ensures that it is powered up.
*
* Any runtime pm reference obtained by this function must have a symmetric
* call to intel_runtime_pm_put() to release the reference again.
*
* Returns: the wakeref cookie to pass to intel_runtime_pm_put()
*/
intel_wakeref_t intel_runtime_pm_get(struct intel_runtime_pm *rpm)
{
return __intel_runtime_pm_get(rpm, true);
}
/**
* __intel_runtime_pm_get_if_active - grab a runtime pm reference if device is active
* @rpm: the intel_runtime_pm structure
* @ignore_usecount: get a ref even if dev->power.usage_count is 0
*
* This function grabs a device-level runtime pm reference if the device is
* already active and ensures that it is powered up. It is illegal to try
* and access the HW should intel_runtime_pm_get_if_active() report failure.
*
* If @ignore_usecount is true, a reference will be acquired even if there is no
* user requiring the device to be powered up (dev->power.usage_count == 0).
* If the function returns false in this case then it's guaranteed that the
* device's runtime suspend hook has been called already or that it will be
* called (and hence it's also guaranteed that the device's runtime resume
* hook will be called eventually).
*
* Any runtime pm reference obtained by this function must have a symmetric
* call to intel_runtime_pm_put() to release the reference again.
*
* Returns: the wakeref cookie to pass to intel_runtime_pm_put(), evaluates
* as True if the wakeref was acquired, or False otherwise.
*/
static intel_wakeref_t __intel_runtime_pm_get_if_active(struct intel_runtime_pm *rpm,
bool ignore_usecount)
{
if (IS_ENABLED(CONFIG_PM)) {
/*
* In cases runtime PM is disabled by the RPM core and we get
* an -EINVAL return value we are not supposed to call this
* function, since the power state is undefined. This applies
* atm to the late/early system suspend/resume handlers.
*/
if ((ignore_usecount &&
pm_runtime_get_if_active(rpm->kdev) <= 0) ||
(!ignore_usecount &&
pm_runtime_get_if_in_use(rpm->kdev) <= 0))
return 0;
}
intel_runtime_pm_acquire(rpm, true);
return track_intel_runtime_pm_wakeref(rpm);
}
intel_wakeref_t intel_runtime_pm_get_if_in_use(struct intel_runtime_pm *rpm)
{
return __intel_runtime_pm_get_if_active(rpm, false);
}
intel_wakeref_t intel_runtime_pm_get_if_active(struct intel_runtime_pm *rpm)
{
return __intel_runtime_pm_get_if_active(rpm, true);
}
/**
* intel_runtime_pm_get_noresume - grab a runtime pm reference
* @rpm: the intel_runtime_pm structure
*
* This function grabs a device-level runtime pm reference.
*
* It will _not_ resume the device but instead only get an extra wakeref.
* Therefore it is only valid to call this functions from contexts where
* the device is known to be active and with another wakeref previously hold.
*
* Any runtime pm reference obtained by this function must have a symmetric
* call to intel_runtime_pm_put() to release the reference again.
*
* Returns: the wakeref cookie to pass to intel_runtime_pm_put()
*/
intel_wakeref_t intel_runtime_pm_get_noresume(struct intel_runtime_pm *rpm)
{
assert_rpm_raw_wakeref_held(rpm);
pm_runtime_get_noresume(rpm->kdev);
intel_runtime_pm_acquire(rpm, true);
return track_intel_runtime_pm_wakeref(rpm);
}
static void __intel_runtime_pm_put(struct intel_runtime_pm *rpm,
intel_wakeref_t wref,
bool wakelock)
{
struct device *kdev = rpm->kdev;
untrack_intel_runtime_pm_wakeref(rpm, wref);
intel_runtime_pm_release(rpm, wakelock);
pm_runtime_mark_last_busy(kdev);
pm_runtime_put_autosuspend(kdev);
}
/**
* intel_runtime_pm_put_raw - release a raw runtime pm reference
* @rpm: the intel_runtime_pm structure
* @wref: wakeref acquired for the reference that is being released
*
* This function drops the device-level runtime pm reference obtained by
* intel_runtime_pm_get_raw() and might power down the corresponding
* hardware block right away if this is the last reference.
*/
void
intel_runtime_pm_put_raw(struct intel_runtime_pm *rpm, intel_wakeref_t wref)
{
__intel_runtime_pm_put(rpm, wref, false);
}
/**
* intel_runtime_pm_put_unchecked - release an unchecked runtime pm reference
* @rpm: the intel_runtime_pm structure
*
* This function drops the device-level runtime pm reference obtained by
* intel_runtime_pm_get() and might power down the corresponding
* hardware block right away if this is the last reference.
*
* This function exists only for historical reasons and should be avoided in
* new code, as the correctness of its use cannot be checked. Always use
* intel_runtime_pm_put() instead.
*/
void intel_runtime_pm_put_unchecked(struct intel_runtime_pm *rpm)
{
__intel_runtime_pm_put(rpm, -1, true);
}
#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM)
/**
* intel_runtime_pm_put - release a runtime pm reference
* @rpm: the intel_runtime_pm structure
* @wref: wakeref acquired for the reference that is being released
*
* This function drops the device-level runtime pm reference obtained by
* intel_runtime_pm_get() and might power down the corresponding
* hardware block right away if this is the last reference.
*/
void intel_runtime_pm_put(struct intel_runtime_pm *rpm, intel_wakeref_t wref)
{
__intel_runtime_pm_put(rpm, wref, true);
}
#endif
/**
* intel_runtime_pm_enable - enable runtime pm
* @rpm: the intel_runtime_pm structure
*
* This function enables runtime pm at the end of the driver load sequence.
*
* Note that this function does currently not enable runtime pm for the
* subordinate display power domains. That is done by
* intel_power_domains_enable().
*/
void intel_runtime_pm_enable(struct intel_runtime_pm *rpm)
{
struct drm_i915_private *i915 = rpm_to_i915(rpm);
struct device *kdev = rpm->kdev;
/*
* Disable the system suspend direct complete optimization, which can
* leave the device suspended skipping the driver's suspend handlers
* if the device was already runtime suspended. This is needed due to
* the difference in our runtime and system suspend sequence and
* becaue the HDA driver may require us to enable the audio power
* domain during system suspend.
*/
dev_pm_set_driver_flags(kdev, DPM_FLAG_NO_DIRECT_COMPLETE);
pm_runtime_set_autosuspend_delay(kdev, 10000); /* 10s */
pm_runtime_mark_last_busy(kdev);
/*
* Take a permanent reference to disable the RPM functionality and drop
* it only when unloading the driver. Use the low level get/put helpers,
* so the driver's own RPM reference tracking asserts also work on
* platforms without RPM support.
*/
if (!rpm->available) {
int ret;
pm_runtime_dont_use_autosuspend(kdev);
ret = pm_runtime_get_sync(kdev);
drm_WARN(&i915->drm, ret < 0,
"pm_runtime_get_sync() failed: %d\n", ret);
} else {
pm_runtime_use_autosuspend(kdev);
}
/*
* FIXME: Temp hammer to keep autosupend disable on lmem supported platforms.
* As per PCIe specs 5.3.1.4.1, all iomem read write request over a PCIe
* function will be unsupported in case PCIe endpoint function is in D3.
* Let's keep i915 autosuspend control 'on' till we fix all known issue
* with lmem access in D3.
*/
if (!IS_DGFX(i915))
pm_runtime_allow(kdev);
/*
* The core calls the driver load handler with an RPM reference held.
* We drop that here and will reacquire it during unloading in
* intel_power_domains_fini().
*/
pm_runtime_put_autosuspend(kdev);
}
void intel_runtime_pm_disable(struct intel_runtime_pm *rpm)
{
struct drm_i915_private *i915 = rpm_to_i915(rpm);
struct device *kdev = rpm->kdev;
/* Transfer rpm ownership back to core */
drm_WARN(&i915->drm, pm_runtime_get_sync(kdev) < 0,
"Failed to pass rpm ownership back to core\n");
pm_runtime_dont_use_autosuspend(kdev);
if (!rpm->available)
pm_runtime_put(kdev);
}
void intel_runtime_pm_driver_release(struct intel_runtime_pm *rpm)
{
struct drm_i915_private *i915 = rpm_to_i915(rpm);
int count = atomic_read(&rpm->wakeref_count);
intel_wakeref_auto_fini(&rpm->userfault_wakeref);
drm_WARN(&i915->drm, count,
"i915 raw-wakerefs=%d wakelocks=%d on cleanup\n",
intel_rpm_raw_wakeref_count(count),
intel_rpm_wakelock_count(count));
}
void intel_runtime_pm_driver_last_release(struct intel_runtime_pm *rpm)
{
intel_runtime_pm_driver_release(rpm);
untrack_all_intel_runtime_pm_wakerefs(rpm);
}
void intel_runtime_pm_init_early(struct intel_runtime_pm *rpm)
{
struct drm_i915_private *i915 = rpm_to_i915(rpm);
struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
struct device *kdev = &pdev->dev;
rpm->kdev = kdev;
rpm->available = HAS_RUNTIME_PM(i915);
atomic_set(&rpm->wakeref_count, 0);
init_intel_runtime_pm_wakeref(rpm);
INIT_LIST_HEAD(&rpm->lmem_userfault_list);
spin_lock_init(&rpm->lmem_userfault_lock);
intel_wakeref_auto_init(&rpm->userfault_wakeref, i915);
}
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