[Intel-gfx] [PATCH 2/6] drm/i915: add helper functions to get device ptr

[Bharadiya,Pankaj]

Hi Jani, 

On Mon, Jan 13, 2020 at 02:14:51PM +0200, Jani Nikula wrote:
> On Mon, 13 Jan 2020, Pankaj Bharadiya <pankaj.laxminarayan.bharadiya at intel.com> wrote:
> > We will need struct drm_device pointer to pass it to drm_WARN* calls.
> >
> > Add helper functions to exract drm_device pointer from various structs.
> 
> Please don't do this.
> 
> We use the helpers we currently have when they involve something more
> complex than dereferences, such as container_of() or having to use
> dev_get_drvdata() or pci_get_drvdata().

Removing all the helpers will lead to 3 level access depth wherever
struct drm_device pointer is needed and unnecessary complicate the
drm_WARN* calls IMHO.

e.g.: drm_WARN(&vgpu->gvt->dev_priv.drm, 1)

If you are OK with this, I will remove all the helpers and extract
drm_device pointer while calling drm_WARN*() instead and submit
updated patch series.

Thanks,
Pankaj
> 
> I really don't want people to use e.g.
> 
> 	i915_to_dev(i915)
> 
> over
> 
> 	&i915->drm
> 
> 
> BR,
> Jani.
> 
> >
> > Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_display_types.h | 14 ++++++++++++++
> >  drivers/gpu/drm/i915/gvt/gvt.h                     |  5 +++++
> >  drivers/gpu/drm/i915/i915_drv.h                    | 11 +++++++++++
> >  3 files changed, 30 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> > index 7964b3dc0046..765878718fe9 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > @@ -1521,6 +1521,20 @@ dp_to_i915(struct intel_dp *intel_dp)
> >  	return to_i915(dp_to_dig_port(intel_dp)->base.base.dev);
> >  }
> >  
> > +static inline struct drm_device *enc_to_dev(const struct intel_encoder *encoder)
> > +{
> > +	return encoder->base.dev;
> > +}
> > +
> > +static inline struct drm_device *
> > +crtc_state_to_dev(const struct intel_crtc_state *state)
> > +{
> > +	struct intel_crtc *crtc = to_intel_crtc(state->uapi.crtc);
> > +	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> > +
> > +	return i915_to_dev(i915);
> > +}
> > +
> >  static inline struct intel_digital_port *
> >  hdmi_to_dig_port(struct intel_hdmi *intel_hdmi)
> >  {
> > diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
> > index b47c6acaf9c0..d257399b075a 100644
> > --- a/drivers/gpu/drm/i915/gvt/gvt.h
> > +++ b/drivers/gpu/drm/i915/gvt/gvt.h
> > @@ -348,6 +348,11 @@ static inline struct intel_gvt *to_gvt(struct drm_i915_private *i915)
> >  	return i915->gvt;
> >  }
> >  
> > +static inline struct drm_device *vgpu_to_dev(const struct intel_vgpu *vgpu)
> > +{
> > +	return i915_to_dev(vgpu->gvt->dev_priv);
> > +}
> > +
> >  enum {
> >  	INTEL_GVT_REQUEST_EMULATE_VBLANK = 0,
> >  
> > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> > index e7be4c3e43c6..bdc89d021ff8 100644
> > --- a/drivers/gpu/drm/i915/i915_drv.h
> > +++ b/drivers/gpu/drm/i915/i915_drv.h
> > @@ -1325,6 +1325,17 @@ static inline struct drm_i915_private *pdev_to_i915(struct pci_dev *pdev)
> >  	return pci_get_drvdata(pdev);
> >  }
> >  
> > +static inline struct drm_device *i915_to_dev(struct drm_i915_private *i915)
> > +{
> > +	return &i915->drm;
> > +}
> > +
> > +static inline struct drm_device *
> > +perf_stream_to_dev(const struct i915_perf_stream *stream)
> > +{
> > +	return i915_to_dev(stream->perf->i915);
> > +}
> > +
> >  /* Simple iterator over all initialised engines */
> >  #define for_each_engine(engine__, dev_priv__, id__) \
> >  	for ((id__) = 0; \
> 
> -- 
> Jani Nikula, Intel Open Source Graphics Center