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

Jani Nikula
2021-10-14T15:48:36Z

On Thu, 14 Oct 2021, Imre Deak <imre.deak@intel.com> wrote:
> 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).

Simplicity is in the eye of the beholder. ;)

if (!(DISPLAY_VER_BIT(DISPLAY_VER(i915)) & md->display_versions))
return false;

vs.

if (!IS_DISPLAY_VER(i915, md->display_ver_from, md->display_ver_until))
return false;

But okay, to omit the initializations you also need some more magic
here.

BR,
Jani.

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

--
Jani Nikula, Intel Open Source Graphics Center