[Intel-gfx] [PATCH v22 02/13] drm/i915: Eliminate magic numbers "0" and "1" from color plane
Lisovskiy, Stanislav
stanislav.lisovskiy at intel.com
Wed Apr 15 08:19:10 UTC 2020
On Tue, Apr 14, 2020 at 08:36:18PM +0300, Ville Syrjälä wrote:
> On Thu, Apr 09, 2020 at 06:47:19PM +0300, Stanislav Lisovskiy wrote:
> > According to many computer science sources - magic values
> > in code _are_ _bad_. For many reasons: the reason is that "0"
> > or "1" or whatever magic values confuses and doesn't give any
> > info why this parameter is this value and what it's meaning
> > is.
> > I renamed "0" to COLOR_PLANE_Y and "1" to COLOR_PLANE_UV,
> > because we in fact already use this naming in many other places
> > and function names, when dealing with color planes.
> >
> > v2: Removed long line to make checkpatch happy.
> >
> > Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
> > ---
> > .../drm/i915/display/intel_display_types.h | 5 +++
> > drivers/gpu/drm/i915/intel_pm.c | 42 ++++++++++---------
>
> Still super inconsistent with the rest of the driver. Also there's
> the fact that wm_uv doesn't even exist on icl+ so the Y vs. UV naming
> isn't even accurate in a bunch of places.
>
> IMO just drop this for now. We can argue ab out this sort of stuff
> later if we figure out a way to make it consistent across the whole
> driver.
Ok, not saying that this is the best solution, just think that
we should not have expressions like "if (color_plane == 1)" like now.
Good article about this:
https://users.ece.cmu.edu/~eno/coding/CCodingStandard.html#nomagic
Stan
>
> > 2 files changed, 27 insertions(+), 20 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> > index ba8c08145c88..b437182c630a 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > @@ -691,6 +691,11 @@ struct skl_plane_wm {
> > bool is_planar;
> > };
> >
> > +enum color_plane {
> > + COLOR_PLANE_Y,
> > + COLOR_PLANE_UV
> > +};
> > +
> > struct skl_pipe_wm {
> > struct skl_plane_wm planes[I915_MAX_PLANES];
> > };
> > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> > index b632b6bb9c3e..176a28d71822 100644
> > --- a/drivers/gpu/drm/i915/intel_pm.c
> > +++ b/drivers/gpu/drm/i915/intel_pm.c
> > @@ -4013,7 +4013,7 @@ static int skl_compute_wm_params(const struct intel_crtc_state *crtc_state,
> > int width, const struct drm_format_info *format,
> > u64 modifier, unsigned int rotation,
> > u32 plane_pixel_rate, struct skl_wm_params *wp,
> > - int color_plane);
> > + enum color_plane);
> > static void skl_compute_plane_wm(const struct intel_crtc_state *crtc_state,
> > int level,
> > unsigned int latency,
> > @@ -4035,7 +4035,7 @@ skl_cursor_allocation(const struct intel_crtc_state *crtc_state,
> > drm_format_info(DRM_FORMAT_ARGB8888),
> > DRM_FORMAT_MOD_LINEAR,
> > DRM_MODE_ROTATE_0,
> > - crtc_state->pixel_rate, &wp, 0);
> > + crtc_state->pixel_rate, &wp, COLOR_PLANE_Y);
> > drm_WARN_ON(&dev_priv->drm, ret);
> >
> > for (level = 0; level <= max_level; level++) {
> > @@ -4431,7 +4431,7 @@ static u8 skl_compute_dbuf_slices(const struct intel_crtc_state *crtc_state,
> > static u64
> > skl_plane_relative_data_rate(const struct intel_crtc_state *crtc_state,
> > const struct intel_plane_state *plane_state,
> > - int color_plane)
> > + enum color_plane color_plane)
> > {
> > struct intel_plane *plane = to_intel_plane(plane_state->uapi.plane);
> > const struct drm_framebuffer *fb = plane_state->hw.fb;
> > @@ -4446,7 +4446,7 @@ skl_plane_relative_data_rate(const struct intel_crtc_state *crtc_state,
> > if (plane->id == PLANE_CURSOR)
> > return 0;
> >
> > - if (color_plane == 1 &&
> > + if (color_plane == COLOR_PLANE_UV &&
> > !intel_format_info_is_yuv_semiplanar(fb->format, fb->modifier))
> > return 0;
> >
> > @@ -4459,7 +4459,7 @@ skl_plane_relative_data_rate(const struct intel_crtc_state *crtc_state,
> > height = drm_rect_height(&plane_state->uapi.src) >> 16;
> >
> > /* UV plane does 1/2 pixel sub-sampling */
> > - if (color_plane == 1) {
> > + if (color_plane == COLOR_PLANE_UV) {
> > width /= 2;
> > height /= 2;
> > }
> > @@ -4489,12 +4489,12 @@ skl_get_total_relative_data_rate(struct intel_crtc_state *crtc_state,
> > u64 rate;
> >
> > /* packed/y */
> > - rate = skl_plane_relative_data_rate(crtc_state, plane_state, 0);
> > + rate = skl_plane_relative_data_rate(crtc_state, plane_state, COLOR_PLANE_Y);
> > plane_data_rate[plane_id] = rate;
> > total_data_rate += rate;
> >
> > /* uv-plane */
> > - rate = skl_plane_relative_data_rate(crtc_state, plane_state, 1);
> > + rate = skl_plane_relative_data_rate(crtc_state, plane_state, COLOR_PLANE_UV);
> > uv_plane_data_rate[plane_id] = rate;
> > total_data_rate += rate;
> > }
> > @@ -4516,7 +4516,7 @@ icl_get_total_relative_data_rate(struct intel_crtc_state *crtc_state,
> > u64 rate;
> >
> > if (!plane_state->planar_linked_plane) {
> > - rate = skl_plane_relative_data_rate(crtc_state, plane_state, 0);
> > + rate = skl_plane_relative_data_rate(crtc_state, plane_state, COLOR_PLANE_Y);
> > plane_data_rate[plane_id] = rate;
> > total_data_rate += rate;
> > } else {
> > @@ -4533,12 +4533,14 @@ icl_get_total_relative_data_rate(struct intel_crtc_state *crtc_state,
> > continue;
> >
> > /* Y plane rate is calculated on the slave */
> > - rate = skl_plane_relative_data_rate(crtc_state, plane_state, 0);
> > + rate = skl_plane_relative_data_rate(crtc_state, plane_state,
> > + COLOR_PLANE_Y);
> > y_plane_id = plane_state->planar_linked_plane->id;
> > plane_data_rate[y_plane_id] = rate;
> > total_data_rate += rate;
> >
> > - rate = skl_plane_relative_data_rate(crtc_state, plane_state, 1);
> > + rate = skl_plane_relative_data_rate(crtc_state, plane_state,
> > + COLOR_PLANE_UV);
> > plane_data_rate[plane_id] = rate;
> > total_data_rate += rate;
> > }
> > @@ -4854,14 +4856,14 @@ skl_compute_wm_params(const struct intel_crtc_state *crtc_state,
> > int width, const struct drm_format_info *format,
> > u64 modifier, unsigned int rotation,
> > u32 plane_pixel_rate, struct skl_wm_params *wp,
> > - int color_plane)
> > + enum color_plane color_plane)
> > {
> > struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> > struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> > u32 interm_pbpl;
> >
> > /* only planar format has two planes */
> > - if (color_plane == 1 &&
> > + if (color_plane == COLOR_PLANE_UV &&
> > !intel_format_info_is_yuv_semiplanar(format, modifier)) {
> > drm_dbg_kms(&dev_priv->drm,
> > "Non planar format have single plane\n");
> > @@ -4878,7 +4880,7 @@ skl_compute_wm_params(const struct intel_crtc_state *crtc_state,
> > wp->is_planar = intel_format_info_is_yuv_semiplanar(format, modifier);
> >
> > wp->width = width;
> > - if (color_plane == 1 && wp->is_planar)
> > + if (color_plane == COLOR_PLANE_UV && wp->is_planar)
> > wp->width /= 2;
> >
> > wp->cpp = format->cpp[color_plane];
> > @@ -4945,7 +4947,7 @@ skl_compute_wm_params(const struct intel_crtc_state *crtc_state,
> > static int
> > skl_compute_plane_wm_params(const struct intel_crtc_state *crtc_state,
> > const struct intel_plane_state *plane_state,
> > - struct skl_wm_params *wp, int color_plane)
> > + struct skl_wm_params *wp, enum color_plane color_plane)
> > {
> > const struct drm_framebuffer *fb = plane_state->hw.fb;
> > int width;
> > @@ -5187,7 +5189,7 @@ static void skl_compute_transition_wm(const struct intel_crtc_state *crtc_state,
> >
> > static int skl_build_plane_wm_single(struct intel_crtc_state *crtc_state,
> > const struct intel_plane_state *plane_state,
> > - enum plane_id plane_id, int color_plane)
> > + enum plane_id plane_id, enum color_plane color_plane)
> > {
> > struct skl_plane_wm *wm = &crtc_state->wm.skl.optimal.planes[plane_id];
> > struct skl_wm_params wm_params;
> > @@ -5216,7 +5218,7 @@ static int skl_build_plane_wm_uv(struct intel_crtc_state *crtc_state,
> >
> > /* uv plane watermarks must also be validated for NV12/Planar */
> > ret = skl_compute_plane_wm_params(crtc_state, plane_state,
> > - &wm_params, 1);
> > + &wm_params, COLOR_PLANE_UV);
> > if (ret)
> > return ret;
> >
> > @@ -5237,7 +5239,7 @@ static int skl_build_plane_wm(struct intel_crtc_state *crtc_state,
> > return 0;
> >
> > ret = skl_build_plane_wm_single(crtc_state, plane_state,
> > - plane_id, 0);
> > + plane_id, COLOR_PLANE_Y);
> > if (ret)
> > return ret;
> >
> > @@ -5270,17 +5272,17 @@ static int icl_build_plane_wm(struct intel_crtc_state *crtc_state,
> > fb->format->num_planes == 1);
> >
> > ret = skl_build_plane_wm_single(crtc_state, plane_state,
> > - y_plane_id, 0);
> > + y_plane_id, COLOR_PLANE_Y);
> > if (ret)
> > return ret;
> >
> > ret = skl_build_plane_wm_single(crtc_state, plane_state,
> > - plane_id, 1);
> > + plane_id, COLOR_PLANE_UV);
> > if (ret)
> > return ret;
> > } else if (intel_wm_plane_visible(crtc_state, plane_state)) {
> > ret = skl_build_plane_wm_single(crtc_state, plane_state,
> > - plane_id, 0);
> > + plane_id, COLOR_PLANE_Y);
> > if (ret)
> > return ret;
> > }
> > --
> > 2.24.1.485.gad05a3d8e5
>
> --
> Ville Syrjälä
> Intel
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