Re: [PATCH] drm/i915: reset forcewake count after reset

[Chris Wilson <chris@chris-wilson.co.uk>]

On Thu, 23 Jun 2011 16:06:22 -0700, Ben Widawsky <ben@bwidawsk.net> wrote:
> 
> Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> ---
>  drivers/gpu/drm/i915/i915_drv.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 0defd42..9292499 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -579,6 +579,7 @@ int i915_reset(struct drm_device *dev, u8 flags)
>  	} else switch (INTEL_INFO(dev)->gen) {
>  	case 6:
>  		ret = gen6_do_reset(dev, flags);
> +		atomic_set(&dev_priv->forcewake_count, 0);
>  		break;
>  	case 5:
>  		ret = ironlake_do_reset(dev, flags);

Can forcewake be non-zero here? If it has been bumped by a user wakelock,
then what happens when that is subsequently released? I don't think this
is safe...

What scenario are you trying to fix?
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre