[Intel-gfx] [PATCH v2 3/4] drm/i915: Call uncore_suspend before platform suspend handlers

[Imre Deak]

On Thu, Jul 06, 2017 at 09:24:49PM +0200, Hans de Goede wrote:
> Quoting Ville: "the forcewake timer might still be active until the uncore
> suspend, and having active forcewakes while we've already told the GT wake
> stuff to stop acting normally doesn't seem quite right to me."
> 
> Reported-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Suggested-by: Imre Deak <imre.deak at intel.com>
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>

> ---
> Changes in v2:
> -Rebase on current (July 6th 2017) drm-next
> ---
>  drivers/gpu/drm/i915/i915_drv.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index ce31d9ed23dc..4a6cd3176e0a 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -2415,6 +2415,8 @@ static int intel_runtime_suspend(struct device *kdev)
>  
>  	intel_runtime_pm_disable_interrupts(dev_priv);
>  
> +	intel_uncore_suspend(dev_priv);
> +

Yep, this fixes a problem on VLV independent of your IOSF/forcewake
fix. vlv_suspend_complete() calls vlv_allow_gt_wake(false) after which
we shouldn't have any pending forcewakes until resume.

AFAICS after this point there isn't anything requiring forcewake until
resume so the change looks ok:

Reviewed-by: Imre Deak <imre.deak at intel.com>

>  	ret = 0;
>  	if (IS_GEN9_LP(dev_priv)) {
>  		bxt_display_core_uninit(dev_priv);
> @@ -2427,6 +2429,8 @@ static int intel_runtime_suspend(struct device *kdev)
>  
>  	if (ret) {
>  		DRM_ERROR("Runtime suspend failed, disabling it (%d)\n", ret);
> +		intel_uncore_runtime_resume(dev_priv);
> +
>  		intel_runtime_pm_enable_interrupts(dev_priv);
>  
>  		enable_rpm_wakeref_asserts(dev_priv);
> @@ -2434,8 +2438,6 @@ static int intel_runtime_suspend(struct device *kdev)
>  		return ret;
>  	}
>  
> -	intel_uncore_suspend(dev_priv);
> -
>  	enable_rpm_wakeref_asserts(dev_priv);
>  	WARN_ON_ONCE(atomic_read(&dev_priv->pm.wakeref_count));
>  
> -- 
> 2.13.0
>