diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 21587f89f44bf8981b3556026ab8261b40de1230..bd9549de4a3b57b8a352317a7535f698b55c973b 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -3559,6 +3559,37 @@ void intel_sanitize_pm(struct drm_device *dev) dev_priv->display.sanitize_pm(dev); } +/* Starting with Haswell, we have different power wells for + * different parts of the GPU. This attempts to enable them all. + */ +void intel_init_power_wells(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + unsigned long power_wells[] = { + HSW_PWR_WELL_CTL1, + HSW_PWR_WELL_CTL2, + HSW_PWR_WELL_CTL4 + }; + int i; + + if (!IS_HASWELL(dev)) + return; + + mutex_lock(&dev->struct_mutex); + + for (i = 0; i < ARRAY_SIZE(power_wells); i++) { + int well = I915_READ(power_wells[i]); + + if ((well & HSW_PWR_WELL_STATE) == 0) { + I915_WRITE(power_wells[i], well & HSW_PWR_WELL_ENABLE); + if (wait_for(I915_READ(power_wells[i] & HSW_PWR_WELL_STATE), 20)) + DRM_ERROR("Error enabling power well %lx\n", power_wells[i]); + } + } + + mutex_unlock(&dev->struct_mutex); +} + /* Set up chip specific power management-related functions */ void intel_init_pm(struct drm_device *dev) { @@ -3707,5 +3738,10 @@ void intel_init_pm(struct drm_device *dev) else dev_priv->display.get_fifo_size = i830_get_fifo_size; } + + /* We attempt to init the necessary power wells early in the initialization + * time, so the subsystems that expect power to be enabled can work. + */ + intel_init_power_wells(dev); }