Re: [Intel-gfx] [PATCH 01/11] drm/i915: Add a table with a descriptor for all i915 modifiers

Imre Deak
2021-10-14T15:04:28Z

On Thu, Oct 14, 2021 at 05:07:16PM +0300, Jani Nikula wrote:
> On Thu, 07 Oct 2021, Imre Deak <imre.deak@intel.com> wrote:
> > Add a table describing all the framebuffer modifiers used by i915 at one
> > place. This has the benefit of deduplicating the listing of supported
> > modifiers for each platform and checking the support of these modifiers
> > on a given plane. This also simplifies in a similar way getting some
> > attribute for a modifier, for instance checking if the modifier is a
> > CCS modifier type.
>
> Just some high level comments inline.
>
> >
> > Signed-off-by: Imre Deak <imre.deak@intel.com>
> > ---
> > drivers/gpu/drm/i915/display/intel_cursor.c | 19 +-
> > .../drm/i915/display/intel_display_types.h | 1 -
> > drivers/gpu/drm/i915/display/intel_fb.c | 178 ++++++++++++++++++
> > drivers/gpu/drm/i915/display/intel_fb.h | 8 +
> > drivers/gpu/drm/i915/display/intel_sprite.c | 35 +---
> > drivers/gpu/drm/i915/display/skl_scaler.c | 1 +
> > .../drm/i915/display/skl_universal_plane.c | 137 +-------------
> > drivers/gpu/drm/i915/i915_drv.h | 3 +
> > 8 files changed, 218 insertions(+), 164 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_cursor.c b/drivers/gpu/drm/i915/display/intel_cursor.c
> > index f6dcb5aa63f64..bcd44ff30ce5b 100644
> > --- a/drivers/gpu/drm/i915/display/intel_cursor.c
> > +++ b/drivers/gpu/drm/i915/display/intel_cursor.c
> > @@ -28,11 +28,6 @@ static const u32 intel_cursor_formats[] = {
> > DRM_FORMAT_ARGB8888,
> > };
> >
> > -static const u64 cursor_format_modifiers[] = {
> > - DRM_FORMAT_MOD_LINEAR,
> > - DRM_FORMAT_MOD_INVALID
> > -};
> > -
> > static u32 intel_cursor_base(const struct intel_plane_state *plane_state)
> > {
> > struct drm_i915_private *dev_priv =
> > @@ -605,8 +600,10 @@ static bool i9xx_cursor_get_hw_state(struct intel_plane *plane,
> > static bool intel_cursor_format_mod_supported(struct drm_plane *_plane,
> > u32 format, u64 modifier)
> > {
> > - return modifier == DRM_FORMAT_MOD_LINEAR &&
> > - format == DRM_FORMAT_ARGB8888;
> > + if (!intel_fb_plane_supports_modifier(to_intel_plane(_plane), modifier))
> > + return false;
> > +
> > + return format == DRM_FORMAT_ARGB8888;
> > }
> >
> > static int
> > @@ -754,6 +751,7 @@ intel_cursor_plane_create(struct drm_i915_private *dev_priv,
> > {
> > struct intel_plane *cursor;
> > int ret, zpos;
> > + u64 *modifiers;
> >
> > cursor = intel_plane_alloc();
> > if (IS_ERR(cursor))
> > @@ -784,13 +782,18 @@ intel_cursor_plane_create(struct drm_i915_private *dev_priv,
> > if (IS_I845G(dev_priv) || IS_I865G(dev_priv) || HAS_CUR_FBC(dev_priv))
> > cursor->cursor.size = ~0;
> >
> > + modifiers = intel_fb_plane_get_modifiers(dev_priv, pipe, cursor->id);
> > +
> > ret = drm_universal_plane_init(&dev_priv->drm, &cursor->base,
> > 0, &intel_cursor_plane_funcs,
> > intel_cursor_formats,
> > ARRAY_SIZE(intel_cursor_formats),
> > - cursor_format_modifiers,
> > + modifiers,
> > DRM_PLANE_TYPE_CURSOR,
> > "cursor %c", pipe_name(pipe));
> > +
> > + kfree(modifiers);
> > +
> > if (ret)
> > goto fail;
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> > index 21ce8bccc645a..bb53b01f07aee 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > @@ -1336,7 +1336,6 @@ struct intel_plane {
> > enum plane_id id;
> > enum pipe pipe;
> > bool has_fbc;
> > - bool has_ccs;
> > bool need_async_flip_disable_wa;
> > u32 frontbuffer_bit;
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_fb.c b/drivers/gpu/drm/i915/display/intel_fb.c
> > index fa1f375e696bf..aefae988b620b 100644
> > --- a/drivers/gpu/drm/i915/display/intel_fb.c
> > +++ b/drivers/gpu/drm/i915/display/intel_fb.c
> > @@ -13,6 +13,184 @@
> >
> > #define check_array_bounds(i915, a, i) drm_WARN_ON(&(i915)->drm, (i) >= ARRAY_SIZE(a))
> >
> > +const struct intel_modifier_desc {
>
> static?

Yes, will fix this.

> Maybe split the struct declaration and the array definition for
> clarity. *shrug*

Ok.

> > + u64 id;
> > + u64 display_versions;
> > +
> > + struct {
> > +#define INTEL_CCS_RC BIT(0)
> > +#define INTEL_CCS_RC_CC BIT(1)
> > +#define INTEL_CCS_MC BIT(2)
> > +
> > +#define INTEL_CCS_ANY (INTEL_CCS_RC | INTEL_CCS_RC_CC | INTEL_CCS_MC)
> > + u8 type:3;
> > + } ccs;
> > +} intel_modifiers[] = {
> > + {
> > + .id = DRM_FORMAT_MOD_LINEAR,
> > + .display_versions = DISPLAY_VER_MASK_ALL,
>
> What is this going to look like when display version mask isn't fine
> grained enough to cover all the platforms? Do we have cases like that
> already?

Display 13 platforms will have different modifiers enabled, but they can
be distinguished with a modifier attribute.

> [snip]
>
> > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> > index 12256218634f4..a92228c922a54 100644
> > --- a/drivers/gpu/drm/i915/i915_drv.h
> > +++ b/drivers/gpu/drm/i915/i915_drv.h
> > @@ -1342,6 +1342,9 @@ static inline struct drm_i915_private *pdev_to_i915(struct pci_dev *pdev)
> > #define DISPLAY_VER(i915) (INTEL_INFO(i915)->display.ver)
> > #define IS_DISPLAY_VER(i915, from, until) \
> > (DISPLAY_VER(i915) >= (from) && DISPLAY_VER(i915) <= (until))
> > +#define DISPLAY_VER_BIT(d) BIT_ULL(d)
> > +#define DISPLAY_VER_MASK(f, u) GENMASK_ULL(u, f)
> > +#define DISPLAY_VER_MASK_ALL DISPLAY_VER_MASK(0, BITS_PER_LONG_LONG - 1)
>
> Do we want to promote this usage all over the place? Maybe keep them
> internal to intel_fb.c?
>
> Or just add both from and until members in intel_modifier_desc, and use
> the regular IS_DISPLAY_VER() in intel_fb.c as well. It's not worse
> considering the mask you have is u64. You could have two u8's
> instead.
>
> You could consider 0 for either to mean "no limit", and skip
> the initialization instead of duplicating .display_versions =
> DISPLAY_VER_MASK_ALL.
>
> I think I'd prefer that. Or do you see masks with gaps in them?

No, just continuous ranges atm.

Ok, I can change these to two u8s instead, though I would prefer the
simpler way of checking a bitmask. But yes, it requires a u64 (or u32
which would be enough for now).

> BR,
> Jani.
>
>
> >
> > #define INTEL_REVID(dev_priv) (to_pci_dev((dev_priv)->drm.dev)->revision)
>
> --
> Jani Nikula, Intel Open Source Graphics Center