Re: [PATCH] drm/i915: Init power domains early in driver load

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Thu, Jan 07, 2016 at 12:44:21PM +0100, Daniel Vetter wrote:
> Since
> 
> commit ac9b8236551d1177fd07b56aef9b565d1864420d
> Author: Ville Syrj�l� <ville.syrjala@linux.intel.com>
> Date:   Fri Nov 27 18:55:26 2015 +0200
> 
>     drm/i915: Introduce a gmbus power domain
> 
> gmbus also needs the power domain infrastructure right from the start,
> since as soon as we register the i2c controllers someone can use them.
> 
> v2: Adjust cleanup paths too (Chris).
> 
> Cc: Ville Syrj�l� <ville.syrjala@linux.intel.com>
> Cc: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
> Cc: Imre Deak <imre.deak@intel.com>
> Cc: Jani Nikula <jani.nikula@intel.com>
> Cc: Meelis Roos <mroos@linux.ee>
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Fixes: ac9b8236551d ("drm/i915: Introduce a gmbus power domain")
> Cc: stable@vger.kernel.org
> References: http://www.spinics.net/lists/intel-gfx/msg83075.html
> Tested-by: Meelis Roos <mroos@linux.ee>
> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> ---
>  drivers/gpu/drm/i915/i915_dma.c | 11 +++++------
>  1 file changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
> index 988a3806512a..490d8b0d931e 100644
> --- a/drivers/gpu/drm/i915/i915_dma.c
> +++ b/drivers/gpu/drm/i915/i915_dma.c
> @@ -398,7 +398,6 @@ static int i915_load_modeset_init(struct drm_device *dev)
>  	if (ret)
>  		goto cleanup_vga_switcheroo;
>  
> -	intel_power_domains_init_hw(dev_priv, false);
>  
>  	intel_csr_ucode_init(dev_priv);
>  
> @@ -1025,6 +1024,8 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
>  
>  	intel_irq_init(dev_priv);
>  	intel_uncore_sanitize(dev);
> +	intel_power_domains_init(dev_priv);
> +	intel_power_domains_init_hw(dev_priv);

I think intel_init_dpio() needs to be moved too. We need to know the
DPIO IOSF ports before attempting to talk to the PHY (which can happen
from intel_power_domains_init_hw()).

I'm also wondering why we're doing gmbus init this early. We shouldn't
need it until modeset init.

>  
>  	/* Try to make sure MCHBAR is enabled before poking at it */
>  	intel_setup_mchbar(dev);
> @@ -1057,12 +1058,10 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
>  			goto out_gem_unload;
>  	}
>  
> -	intel_power_domains_init(dev_priv);
> -
>  	ret = i915_load_modeset_init(dev);
>  	if (ret < 0) {
>  		DRM_ERROR("failed to init modeset\n");
> -		goto out_power_well;
> +		goto out_vblank;
>  	}
>  
>  	/*
> @@ -1091,8 +1090,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
>  
>  	return 0;
>  
> -out_power_well:
> -	intel_power_domains_fini(dev_priv);
> +out_vblank:
>  	drm_vblank_cleanup(dev);
>  out_gem_unload:
>  	WARN_ON(unregister_oom_notifier(&dev_priv->mm.oom_notifier));
> @@ -1103,6 +1101,7 @@ out_gem_unload:
>  
>  	intel_teardown_gmbus(dev);
>  	intel_teardown_mchbar(dev);
> +	intel_power_domains_fini(dev_priv);
>  	pm_qos_remove_request(&dev_priv->pm_qos);
>  	destroy_workqueue(dev_priv->gpu_error.hangcheck_wq);
>  out_freedpwq:
> -- 
> 2.6.4

-- 
Ville Syrj�l�
Intel OTC