Commit dc48529f authored by David Francis's avatar David Francis Committed by Alex Deucher
Browse files

drm/dp_mst: Add PBN calculation for DSC modes 



With DSC, bpp can be fractional in multiples of 1/16.

Change drm_dp_calc_pbn_mode to reflect this, adding a new
parameter bool dsc. When this parameter is true, treat the
bpp parameter as having units not of bits per pixel, but
1/16 of a bit per pixel

v2: Don't add separate function for this
v3: In the equation divide bpp by 16 as it is expected
not to leave any remainder
v4: Added DSC test parameters for selftest

Reviewed-by: default avatarManasi Navare <manasi.d.navare@intel.com>
Reviewed-by: default avatarLyude Paul <lyude@redhat.com>
Reviewed-by: default avatarHarry Wentland <harry.wentland@amd.com>
Signed-off-by: default avatarDavid Francis <David.Francis@amd.com>
Signed-off-by: default avatarMikita Lipski <mikita.lipski@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 0f899fd4

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

+1 −1
Original line number Diff line number Diff line
@@ -4933,7 +4933,7 @@ static int dm_encoder_helper_atomic_check(struct drm_encoder *encoder, 
								    is_y420);

		bpp = convert_dc_color_depth_into_bpc(color_depth) * 3;

		clock = adjusted_mode->clock;

		dm_new_connector_state->pbn = drm_dp_calc_pbn_mode(clock, bpp);

		dm_new_connector_state->pbn = drm_dp_calc_pbn_mode(clock, bpp, false);

	}

	dm_new_connector_state->vcpi_slots = drm_dp_atomic_find_vcpi_slots(state,

									   mst_mgr,

drivers/gpu/drm/drm_dp_mst_topology.c

+11 −1
Original line number Diff line number Diff line
@@ -4415,10 +4415,11 @@ EXPORT_SYMBOL(drm_dp_check_act_status); 
 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.

 * @clock: dot clock for the mode

 * @bpp: bpp for the mode.

 * @dsc: DSC mode. If true, bpp has units of 1/16 of a bit per pixel

 *

 * This uses the formula in the spec to calculate the PBN value for a mode.

 */

int drm_dp_calc_pbn_mode(int clock, int bpp)

int drm_dp_calc_pbn_mode(int clock, int bpp, bool dsc)

{

	/*

	 * margin 5300ppm + 300ppm ~ 0.6% as per spec, factor is 1.006
@@ -4429,7 +4430,16 @@ int drm_dp_calc_pbn_mode(int clock, int bpp) 
	 * peak_kbps *= (1006/1000)

	 * peak_kbps *= (64/54)

	 * peak_kbps *= 8    convert to bytes

	 *

	 * If the bpp is in units of 1/16, further divide by 16. Put this

	 * factor in the numerator rather than the denominator to avoid

	 * integer overflow

	 */



	if (dsc)

		return DIV_ROUND_UP_ULL(mul_u32_u32(clock * (bpp / 16), 64 * 1006),

					8 * 54 * 1000 * 1000);



	return DIV_ROUND_UP_ULL(mul_u32_u32(clock * bpp, 64 * 1006),

				8 * 54 * 1000 * 1000);

}

drivers/gpu/drm/i915/display/intel_dp_mst.c

+2 −1
Original line number Diff line number Diff line
@@ -61,7 +61,8 @@ static int intel_dp_mst_compute_link_config(struct intel_encoder *encoder, 
		crtc_state->pipe_bpp = bpp;



		crtc_state->pbn = drm_dp_calc_pbn_mode(adjusted_mode->crtc_clock,

						       crtc_state->pipe_bpp);

						       crtc_state->pipe_bpp,

						       false);



		slots = drm_dp_atomic_find_vcpi_slots(state, &intel_dp->mst_mgr,

						      port, crtc_state->pbn);

drivers/gpu/drm/nouveau/dispnv50/disp.c

+1 −1
Original line number Diff line number Diff line
@@ -806,7 +806,7 @@ nv50_msto_atomic_check(struct drm_encoder *encoder, 
		 * topology

		 */

		asyh->or.bpc = min(connector->display_info.bpc, 8U);

		asyh->dp.pbn = drm_dp_calc_pbn_mode(clock, asyh->or.bpc * 3);

		asyh->dp.pbn = drm_dp_calc_pbn_mode(clock, asyh->or.bpc * 3, false);

	}



	slots = drm_dp_atomic_find_vcpi_slots(state, &mstm->mgr, mstc->port,

drivers/gpu/drm/radeon/radeon_dp_mst.c

+1 −1
Original line number Diff line number Diff line
@@ -518,7 +518,7 @@ static bool radeon_mst_mode_fixup(struct drm_encoder *encoder, 


	mst_enc = radeon_encoder->enc_priv;



	mst_enc->pbn = drm_dp_calc_pbn_mode(adjusted_mode->clock, bpp);

	mst_enc->pbn = drm_dp_calc_pbn_mode(adjusted_mode->clock, bpp, false);



	mst_enc->primary->active_device = mst_enc->primary->devices & mst_enc->connector->devices;

	DRM_DEBUG_KMS("setting active device to %08x from %08x %08x for encoder %d\n",