Re: [DPU PATCH 4/7] drm/msm/dpu: switch to drm zpos property

[Sean Paul <seanpaul-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>]

On Wed, May 23, 2018 at 03:21:15PM -0600, Jordan Crouse wrote:
> On Wed, May 23, 2018 at 12:30:59PM -0700, Jeykumar Sankaran wrote:
> > Replace custom plane zpos property with drm core zpos
> > property. CRTC relies on the normalized zpos values
> > to configure blend stages of each plane.
> > 
> > Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
> > ---
> >  drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c  | 36 +------------------------------
> >  drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 18 +++++++++++++---
> >  2 files changed, 16 insertions(+), 38 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > index d439a9e..a0b702f 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > @@ -2631,24 +2631,6 @@ struct plane_state {
> >  	u32 pipe_id;
> >  };
> >  
> > -static int pstate_cmp(const void *a, const void *b)
> > -{
> > -	struct plane_state *pa = (struct plane_state *)a;
> > -	struct plane_state *pb = (struct plane_state *)b;
> > -	int rc = 0;
> > -	int pa_zpos, pb_zpos;
> > -
> > -	pa_zpos = dpu_plane_get_property(pa->dpu_pstate, PLANE_PROP_ZPOS);
> > -	pb_zpos = dpu_plane_get_property(pb->dpu_pstate, PLANE_PROP_ZPOS);
> > -
> > -	if (pa_zpos != pb_zpos)
> > -		rc = pa_zpos - pb_zpos;
> > -	else
> > -		rc = pa->drm_pstate->crtc_x - pb->drm_pstate->crtc_x;
> > -
> > -	return rc;
> > -}
> > -
> >  static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
> >  		struct drm_crtc_state *state)
> >  {
> > @@ -2714,8 +2696,7 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
> >  
> >  		pstates[cnt].dpu_pstate = to_dpu_plane_state(pstate);
> >  		pstates[cnt].drm_pstate = pstate;
> > -		pstates[cnt].stage = dpu_plane_get_property(
> > -				pstates[cnt].dpu_pstate, PLANE_PROP_ZPOS);
> > +		pstates[cnt].stage = pstate->normalized_zpos;
> >  		pstates[cnt].pipe_id = dpu_plane_pipe(plane);
> >  
> >  		/* check dim layer stage with every plane */
> > @@ -2771,21 +2752,6 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
> >  		}
> >  	}
> >  
> > -	/* assign mixer stages based on sorted zpos property */
> > -	sort(pstates, cnt, sizeof(pstates[0]), pstate_cmp, NULL);
> > -
> > -	if (!dpu_is_custom_client()) {
> > -		int stage_old = pstates[0].stage;
> > -
> > -		z_pos = 0;
> > -		for (i = 0; i < cnt; i++) {
> > -			if (stage_old != pstates[i].stage)
> > -				++z_pos;
> > -			stage_old = pstates[i].stage;
> > -			pstates[i].stage = z_pos;
> > -		}
> > -	}
> > -
> >  	z_pos = -1;
> >  	for (i = 0; i < cnt; i++) {
> >  		/* reset counts at every new blend stage */
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> > index b033653..28735c8 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> > @@ -59,6 +59,7 @@
> >  #define DPU_NAME_SIZE  12
> >  
> >  #define DPU_PLANE_COLOR_FILL_FLAG	BIT(31)
> > +#define DPU_ZPOS_MAX 255
> >  
> >  /* multirect rect index */
> >  enum {
> > @@ -1518,9 +1519,6 @@ static void _dpu_plane_install_properties(struct drm_plane *plane,
> >  		/* reserve zpos == 0 for primary planes */
> >  		zpos_def = drm_plane_index(plane) + 1;
> >  	}
> > -
> > -	msm_property_install_range(&pdpu->property_info, "zpos",
> > -		0x0, 0, zpos_max, zpos_def, PLANE_PROP_ZPOS);
> >  }
> >  
> >  static int dpu_plane_atomic_set_property(struct drm_plane *plane,
> > @@ -1958,6 +1956,7 @@ struct drm_plane *dpu_plane_init(struct drm_device *dev,
> >  	struct msm_drm_private *priv;
> >  	struct dpu_kms *kms;
> >  	enum drm_plane_type type;
> > +	int zpos_max = DPU_ZPOS_MAX;
> >  	int ret = -EINVAL;
> >  
> >  	if (!dev) {
> > @@ -2049,6 +2048,19 @@ struct drm_plane *dpu_plane_init(struct drm_device *dev,
> >  	if (ret)
> >  		goto clean_sspp;
> >  
> > +	pdpu->catalog = kms->catalog;
> > +
> > +	if (kms->catalog->mixer_count &&
> > +		kms->catalog->mixer[0].sblk->maxblendstages) {
> > +		zpos_max = kms->catalog->mixer[0].sblk->maxblendstages - 1;
> > +		if (zpos_max > DPU_STAGE_MAX - DPU_STAGE_0 - 1)
> > +			zpos_max = DPU_STAGE_MAX - DPU_STAGE_0 - 1;
> > +	}
> > +
> > +	ret = drm_plane_create_zpos_property(plane, 0, 0, zpos_max);
> > +	if (ret)
> > +		DPU_ERROR("failed to install zpos property, rc = %d\n", ret);
> > +
> 
> drm_plane_create_zpos_property() can either return 0 or -ENOMEM 

This may not always be true.

> so
> printing the return value isn't interesting.

Also if I was reviewing or casual reading this without the ret print, I would
probably leave a comment such as "print the return value" since I don't
generally keep track of all possible return values.

So printing the return value seems reasonable to me.

Sean

> 
> >  	/* success! finalize initialization */
> >  	drm_plane_helper_add(plane, &dpu_plane_helper_funcs);
> >  
> > -- 
> > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> > a Linux Foundation Collaborative Project
> > 
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> 
> -- 
> The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
> a Linux Foundation Collaborative Project

-- 
Sean Paul, Software Engineer, Google / Chromium OS
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