Re: [Intel-gfx] [PATCH v2 14/17] uapi/drm/dg2: Format modifier for DG2 unified compression and clear color

[Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>]

On 21.10.2021 17.35, Ville Syrjälä wrote:
> On Thu, Oct 21, 2021 at 07:56:24PM +0530, Ramalingam C 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.
>>
>> 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>
>> ---
>>   drivers/gpu/drm/i915/display/intel_display.c  |  3 ++
>>   .../drm/i915/display/intel_display_types.h    | 10 +++-
>>   drivers/gpu/drm/i915/display/intel_fb.c       |  7 +++
>>   .../drm/i915/display/skl_universal_plane.c    | 49 +++++++++++++++++--
>>   include/uapi/drm/drm_fourcc.h                 | 30 ++++++++++++
>>   5 files changed, 94 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
>> index 9b678839bf2b..2949fe9f5b9f 100644
>> --- a/drivers/gpu/drm/i915/display/intel_display.c
>> +++ b/drivers/gpu/drm/i915/display/intel_display.c
>> @@ -1013,6 +1013,9 @@ intel_get_format_info(const struct drm_mode_fb_cmd2 *cmd)
>>   					  cmd->pixel_format);
>>   	case I915_FORMAT_MOD_Y_TILED_GEN12_RC_CCS:
>>   	case I915_FORMAT_MOD_Y_TILED_GEN12_MC_CCS:
>> +	case I915_FORMAT_MOD_F_TILED_DG2_RC_CCS:
>> +	case I915_FORMAT_MOD_F_TILED_DG2_MC_CCS:
>> +	case I915_FORMAT_MOD_F_TILED_DG2_RC_CCS_CC:
>>   		return lookup_format_info(gen12_ccs_formats,
>>   					  ARRAY_SIZE(gen12_ccs_formats),
>>   					  cmd->pixel_format);
> 
> That seems not right. Flat CCS is invisible to the user so the format
> info should not include a CCS plane.
> 

I had cleaned out those rc and mc ccs from here long time ago, I wonder 
where did they come back from? On my development tree they're not there. 
Also I915_FORMAT_MOD_F_TILED_DG2_RC_CCS_CC is here in totally wrong 
place, it should have its own gen12_flat_ccs_cc_formats table.

/Juha-Pekka