Re: [Intel-gfx] [Mesa-dev] [PATCH v3 13/17] uapi/drm/dg2: Format modifier for DG2 unified compression and clear color

From: Nanley Chery <nanleychery@gmail.com>
To: Ramalingam C <ramalingam.c@intel.com>
Cc: Simon Ser <contact@emersion.fr>,
	intel-gfx <intel-gfx@lists.freedesktop.org>,
	Kenneth Graunke <kenneth@whitecape.org>,
	dri-devel <dri-devel@lists.freedesktop.org>,
	Slawomir Milczarek <slawomir.milczarek@intel.com>,
	Pekka Paalanen <ppaalanen@gmail.com>,
	Hellstrom Thomas <thomas.hellstrom@intel.com>,
	Matthew Auld <matthew.auld@intel.com>,
	mesa-dev <mesa-dev@lists.freedesktop.org>
Subject: Re: [Intel-gfx] [Mesa-dev] [PATCH v3 13/17] uapi/drm/dg2: Format modifier for DG2 unified compression and clear color
Date: Thu, 9 Dec 2021 14:41:57 -0500	[thread overview]
Message-ID: <CAJDL4uKiQNPm1WMo50m7Q4OPQQF1Ke9Rs8FzSojL_qT7OOaNsw@mail.gmail.com> (raw)
In-Reply-To: <CAJDL4uLzxxjw0vp+en3vVpJFBBBrm-g7PwFVBMMmDZEUoiJp3w@mail.gmail.com>

Ping. I see that a v4 has been sent out without these comments being addressed.

-Nanley

On Tue, Dec 7, 2021 at 6:51 PM Nanley Chery <nanleychery@gmail.com> wrote:
>
> Hi Ramalingam,
>
> On Wed, Oct 27, 2021 at 5:22 PM Ramalingam C <ramalingam.c@intel.com> wrote:
> >
> > From: Matt Roper <matthew.d.roper@intel.com>
> >
> > DG2 unifies render compression and media compression into a single
> > format for the first time.  The programming and buffer layout is
> > supposed to match compression on older gen12 platforms, but the
> > actual compression algorithm is different from any previous platform; as
> > such, we need a new framebuffer modifier to represent buffers in this
> > format, but otherwise we can re-use the existing gen12 compression driver
> > logic.
> >
> > DG2 clear color render compression uses Tile4 layout. Therefore, we need
> > to define a new format modifier for uAPI to support clear color rendering.
> >
>
> I left some feedback on the modifier texts below, but I think it also
> applies to this commit message.
>
> > v2: Rebased on new format modifier check [Ram]
> >
> > Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
> > Signed-off-by: Mika Kahola <mika.kahola@intel.com> (v2)
> > Signed-off-by: Juha-Pekka Heikkilä <juha-pekka.heikkila@intel.com>
> > Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
> > cc: Simon Ser <contact@emersion.fr>
> > Cc: Pekka Paalanen <ppaalanen@gmail.com>
> > Cc: Jordan Justen <jordan.l.justen@intel.com>
> > Cc: Kenneth Graunke <kenneth@whitecape.org>
> > Cc: mesa-dev@lists.freedesktop.org
> > Cc: Tony Ye <tony.ye@intel.com>
> > Cc: Slawomir Milczarek <slawomir.milczarek@intel.com>
> > Acked-by: Simon Ser <contact@emersion.fr>
> > ---
> >  drivers/gpu/drm/i915/display/intel_fb.c       | 43 +++++++++++++++++++
> >  .../drm/i915/display/skl_universal_plane.c    | 29 ++++++++++++-
> >  include/uapi/drm/drm_fourcc.h                 | 30 +++++++++++++
> >  3 files changed, 101 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_fb.c b/drivers/gpu/drm/i915/display/intel_fb.c
> > index 562d5244688d..484ae1fd0e94 100644
> > --- a/drivers/gpu/drm/i915/display/intel_fb.c
> > +++ b/drivers/gpu/drm/i915/display/intel_fb.c
> > @@ -106,6 +106,21 @@ static const struct drm_format_info gen12_ccs_cc_formats[] = {
> >           .hsub = 1, .vsub = 1, .has_alpha = true },
> >  };
> >
> > +static const struct drm_format_info gen12_flat_ccs_cc_formats[] = {
> > +       { .format = DRM_FORMAT_XRGB8888, .depth = 24, .num_planes = 2,
> > +         .char_per_block = { 4, 0 }, .block_w = { 1, 2 }, .block_h = { 1, 1 },
> > +         .hsub = 1, .vsub = 1, },
> > +       { .format = DRM_FORMAT_XBGR8888, .depth = 24, .num_planes = 2,
> > +         .char_per_block = { 4, 0 }, .block_w = { 1, 2 }, .block_h = { 1, 1 },
> > +         .hsub = 1, .vsub = 1, },
> > +       { .format = DRM_FORMAT_ARGB8888, .depth = 32, .num_planes = 2,
> > +         .char_per_block = { 4, 0 }, .block_w = { 1, 2 }, .block_h = { 1, 1 },
> > +         .hsub = 1, .vsub = 1, .has_alpha = true },
> > +       { .format = DRM_FORMAT_ABGR8888, .depth = 32, .num_planes = 2,
> > +         .char_per_block = { 4, 0 }, .block_w = { 1, 2 }, .block_h = { 1, 1 },
> > +         .hsub = 1, .vsub = 1, .has_alpha = true },
> > +};
> > +
> >  struct intel_modifier_desc {
> >         u64 modifier;
> >         struct {
> > @@ -166,6 +181,27 @@ static const struct intel_modifier_desc intel_modifiers[] = {
> >                 .ccs.packed_aux_planes = BIT(1),
> >
> >                 FORMAT_OVERRIDE(gen12_ccs_cc_formats),
> > +       }, {
> > +               .modifier = I915_FORMAT_MOD_4_TILED_DG2_RC_CCS,
> > +               .display_ver = { 12, 13 },
> > +               .tiling = I915_TILING_NONE,
> > +
> > +               .ccs.type = INTEL_CCS_RC,
> > +       }, {
> > +               .modifier = I915_FORMAT_MOD_4_TILED_DG2_MC_CCS,
> > +               .display_ver = { 12, 13 },
> > +               .tiling = I915_TILING_NONE,
> > +
> > +               .ccs.type = INTEL_CCS_MC,
> > +       }, {
> > +               .modifier = I915_FORMAT_MOD_4_TILED_DG2_RC_CCS_CC,
> > +               .display_ver = { 12, 13 },
> > +               .tiling = I915_TILING_NONE,
> > +
> > +               .ccs.type = INTEL_CCS_RC_CC,
> > +               .ccs.cc_planes = BIT(1),
> > +
> > +               FORMAT_OVERRIDE(gen12_flat_ccs_cc_formats),
> >         }, {
> >                 .modifier = I915_FORMAT_MOD_Yf_TILED_CCS,
> >                 .display_ver = { 9, 11 },
> > @@ -582,6 +618,9 @@ intel_tile_width_bytes(const struct drm_framebuffer *fb, int color_plane)
> >                         return 128;
> >                 else
> >                         return 512;
> > +       case I915_FORMAT_MOD_4_TILED_DG2_RC_CCS:
> > +       case I915_FORMAT_MOD_4_TILED_DG2_MC_CCS:
> > +       case I915_FORMAT_MOD_4_TILED_DG2_RC_CCS_CC:
> >         case I915_FORMAT_MOD_4_TILED:
> >                 /*
> >                  * Each 4K tile consists of 64B(8*8) subtiles, with
> > @@ -759,6 +798,10 @@ unsigned int intel_surf_alignment(const struct drm_framebuffer *fb,
> >         case I915_FORMAT_MOD_4_TILED:
> >         case I915_FORMAT_MOD_Yf_TILED:
> >                 return 1 * 1024 * 1024;
> > +       case I915_FORMAT_MOD_4_TILED_DG2_RC_CCS:
> > +       case I915_FORMAT_MOD_4_TILED_DG2_RC_CCS_CC:
> > +       case I915_FORMAT_MOD_4_TILED_DG2_MC_CCS:
> > +               return 16 * 1024;
> >         default:
> >                 MISSING_CASE(fb->modifier);
> >                 return 0;
> > diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c
> > index aeca96925feb..136b3f74a290 100644
> > --- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
> > +++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
> > @@ -753,6 +753,16 @@ static u32 skl_plane_ctl_tiling(u64 fb_modifier)
> >                 return PLANE_CTL_TILED_Y;
> >         case I915_FORMAT_MOD_4_TILED:
> >                 return PLANE_CTL_TILED_4;
> > +       case I915_FORMAT_MOD_4_TILED_DG2_RC_CCS:
> > +               return PLANE_CTL_TILED_4 |
> > +                       PLANE_CTL_RENDER_DECOMPRESSION_ENABLE |
> > +                       PLANE_CTL_CLEAR_COLOR_DISABLE;
> > +       case I915_FORMAT_MOD_4_TILED_DG2_MC_CCS:
> > +               return PLANE_CTL_TILED_4 |
> > +                       PLANE_CTL_MEDIA_DECOMPRESSION_ENABLE |
> > +                       PLANE_CTL_CLEAR_COLOR_DISABLE;
> > +       case I915_FORMAT_MOD_4_TILED_DG2_RC_CCS_CC:
> > +               return PLANE_CTL_TILED_4 | PLANE_CTL_RENDER_DECOMPRESSION_ENABLE;
> >         case I915_FORMAT_MOD_Y_TILED_CCS:
> >         case I915_FORMAT_MOD_Y_TILED_GEN12_RC_CCS_CC:
> >                 return PLANE_CTL_TILED_Y | PLANE_CTL_RENDER_DECOMPRESSION_ENABLE;
> > @@ -1983,6 +1993,9 @@ skl_plane_disable_flip_done(struct intel_plane *plane)
> >  static bool skl_plane_has_rc_ccs(struct drm_i915_private *i915,
> >                                  enum pipe pipe, enum plane_id plane_id)
> >  {
> > +       if (IS_DG2(i915) && !HAS_4TILE(i915))
> > +               return false;
> > +
> >         /* Wa_22011186057 */
> >         if (IS_ADLP_DISPLAY_STEP(i915, STEP_A0, STEP_B0))
> >                 return false;
> > @@ -2001,6 +2014,10 @@ static bool skl_plane_has_rc_ccs(struct drm_i915_private *i915,
> >  static bool gen12_plane_has_mc_ccs(struct drm_i915_private *i915,
> >                                    enum plane_id plane_id)
> >  {
> > +       /* Wa_14013215631:dg2[a0,b0] */
> > +       if (IS_DG2_DISP_STEP(i915, STEP_A0, STEP_C0))
> > +               return false;
> > +
> >         /* Wa_14010477008:tgl[a0..c0],rkl[all],dg1[all] */
> >         if (IS_DG1(i915) || IS_ROCKETLAKE(i915) ||
> >             IS_TGL_DISPLAY_STEP(i915, STEP_A0, STEP_D0))
> > @@ -2243,7 +2260,17 @@ skl_get_initial_plane_config(struct intel_crtc *crtc,
> >                 break;
> >         case PLANE_CTL_TILED_YF: /* aka PLANE_CTL_TILED_4 on XE_LPD+ */
> >                 if (DISPLAY_VER(dev_priv) >= 13) {
> > -                       fb->modifier = I915_FORMAT_MOD_4_TILED;
> > +                       u32 rc_mask = PLANE_CTL_RENDER_DECOMPRESSION_ENABLE |
> > +                                       PLANE_CTL_CLEAR_COLOR_DISABLE;
> > +
> > +                       if ((val & rc_mask) == rc_mask)
> > +                               fb->modifier = I915_FORMAT_MOD_4_TILED_DG2_RC_CCS;
> > +                       else if (val & PLANE_CTL_MEDIA_DECOMPRESSION_ENABLE)
> > +                               fb->modifier = I915_FORMAT_MOD_4_TILED_DG2_MC_CCS;
> > +                       else if (val & PLANE_CTL_RENDER_DECOMPRESSION_ENABLE)
> > +                               fb->modifier = I915_FORMAT_MOD_4_TILED_DG2_RC_CCS_CC;
> > +                       else
> > +                               fb->modifier = I915_FORMAT_MOD_4_TILED;
> >                 } else {
> >                         if (val & PLANE_CTL_RENDER_DECOMPRESSION_ENABLE)
> >                                 fb->modifier = I915_FORMAT_MOD_Yf_TILED_CCS;
> > diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
> > index 982b0a9fa78b..719c17847e07 100644
> > --- a/include/uapi/drm/drm_fourcc.h
> > +++ b/include/uapi/drm/drm_fourcc.h
> > @@ -567,6 +567,36 @@ extern "C" {
> >   */
> >  #define I915_FORMAT_MOD_4_TILED         fourcc_mod_code(INTEL, 12)
> >
> > +/*
> > + * Intel color control surfaces (CCS) for DG2 render compression.
> > + *
> > + * DG2 uses a new compression format for render compression. The general
> > + * layout is the same as I915_FORMAT_MOD_Y_TILED_GEN12_RC_CCS,
> > + * but a new hashing/compression algorithm is used, so a fresh modifier must
> > + * be associated with buffers of this type. Render compression uses 128 byte
> > + * compression blocks.
> > + */
> > +#define I915_FORMAT_MOD_4_TILED_DG2_RC_CCS fourcc_mod_code(INTEL, 13)
> > +
> > +/*
> > + * Intel color control surfaces (CCS) for DG2 media compression.
> > + *
> > + * DG2 uses a new compression format for media compression. The general
> > + * layout is the same as I915_FORMAT_MOD_Y_TILED_GEN12_MC_CCS,
> > + * but a new hashing/compression algorithm is used, so a fresh modifier must
> > + * be associated with buffers of this type. Media compression uses 256 byte
> > + * compression blocks.
> > + */
>
> More so than new compression algorithms, these modifiers are needed
> due to the lack of CCS planes.
>
> The layout of these surfaces are more like I915_FORMAT_MOD_4_TILED, right?
>
> > +#define I915_FORMAT_MOD_4_TILED_DG2_MC_CCS fourcc_mod_code(INTEL, 14)
> > +
> > +/*
> > + * Intel color control surfaces (CCS) for DG2 clear color render compression.
> > + *
> > + * DG2 uses a unified compression format for clear color render compression.
>
> This seems to imply a different format than RC_CCS (with additional
> clear color tracking).
>
> > + * The general layout is a tiled layout using 4Kb tiles i.e. Tile4 layout.
> > + */
>
> It's unclear where the clear color is located from this description
> (by comparison, the GEN12 modifier states that the clear color can be
> found at plane index 2).
>
> Regards,
> Nanley
>
>
> > +#define I915_FORMAT_MOD_4_TILED_DG2_RC_CCS_CC fourcc_mod_code(INTEL, 15)
> > +
> >  /*
> >   * Tiled, NV12MT, grouped in 64 (pixels) x 32 (lines) -sized macroblocks
> >   *
> > --
> > 2.20.1
> >