From 7817381099b4c0418b6c41131b96f89d28a47688 Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Tue, 10 Nov 2015 19:24:06 +0200 Subject: [PATCH 2/3] drm/i915: fix handling of the disable_power_well module option When this option is 0 (so the power well support is disabled) we are supposed to enable all power wells once and don't disable them unless we system suspend the device. Currently if the option is 0, we can call the power well enable handlers multiple times, whenever their refcount changes from 0->1. This may not be a problem for the HW, but it's not logical and may trigger some warnings in the power well code which doesn't expect this. So simply keep around a reference while we are not system suspended to solve this. For simplicity mark the module option read only, so we don't need to deal with re-enabling the feature during runtime. If someone really needs that it could be added later in a more proper way. Signed-off-by: Imre Deak --- drivers/gpu/drm/i915/i915_params.c | 2 +- drivers/gpu/drm/i915/intel_drv.h | 1 + drivers/gpu/drm/i915/intel_runtime_pm.c | 19 ++++++++++++++++++- 3 files changed, 20 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c index 93fc50a..ade9f23 100644 --- a/drivers/gpu/drm/i915/i915_params.c +++ b/drivers/gpu/drm/i915/i915_params.c @@ -125,7 +125,7 @@ module_param_named_unsafe(preliminary_hw_support, i915.preliminary_hw_support, i MODULE_PARM_DESC(preliminary_hw_support, "Enable preliminary hardware support."); -module_param_named_unsafe(disable_power_well, i915.disable_power_well, int, 0600); +module_param_named_unsafe(disable_power_well, i915.disable_power_well, int, 0400); MODULE_PARM_DESC(disable_power_well, "Disable display power wells when possible " "(-1=auto [default], 0=power wells always on, 1=power wells disabled when possible)"); diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 523e553..e0f4115 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1412,6 +1412,7 @@ void intel_psr_single_frame_update(struct drm_device *dev, int intel_power_domains_init(struct drm_i915_private *); void intel_power_domains_fini(struct drm_i915_private *); void intel_power_domains_init_hw(struct drm_i915_private *dev_priv); +void intel_power_domains_suspend(struct drm_i915_private *dev_priv); void intel_runtime_pm_enable(struct drm_i915_private *dev_priv); bool intel_display_power_is_enabled(struct drm_i915_private *dev_priv, diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c index 166c3e9..83630c1 100644 --- a/drivers/gpu/drm/i915/intel_runtime_pm.c +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c @@ -1431,7 +1431,7 @@ void intel_display_power_put(struct drm_i915_private *dev_priv, for_each_power_well_rev(i, power_well, BIT(domain), power_domains) { WARN_ON(!power_well->count); - if (!--power_well->count && i915.disable_power_well) + if (!--power_well->count) intel_power_well_disable(dev_priv, power_well); } @@ -1858,6 +1858,10 @@ void intel_power_domains_fini(struct drm_i915_private *dev_priv) * the power well is not enabled, so just enable it in case * we're going to unload/reload. */ intel_display_set_init_power(dev_priv, true); + + /* Remove the refcount we took to keep power well support disabled. */ + if (!i915.disable_power_well) + intel_display_power_put(dev_priv, POWER_DOMAIN_INIT); } static void intel_power_domains_resume(struct drm_i915_private *dev_priv) @@ -2016,10 +2020,23 @@ void intel_power_domains_init_hw(struct drm_i915_private *dev_priv) /* For now, we need the power well to be always enabled. */ intel_display_set_init_power(dev_priv, true); + /* Disable power support if the user asked so. */ + if (!i915.disable_power_well) + intel_display_power_get(dev_priv, POWER_DOMAIN_INIT); intel_power_domains_resume(dev_priv); power_domains->initializing = false; } +void intel_power_domains_suspend(struct drm_i915_private *dev_priv) +{ + /* + * Even if power well support was disabled we still want to disabled + * we want to disable the power wells while we are system suspended. + */ + if (!i915.disable_power_well) + intel_display_power_put(dev_priv, POWER_DOMAIN_INIT); +} + /** * intel_aux_display_runtime_get - grab an auxiliary power domain reference * @dev_priv: i915 device instance -- 2.5.0