From dc48529fb14ee8450705c00d91f4dcc155e1c2cb Mon Sep 17 00:00:00 2001 From: David Francis Date: Wed, 21 Aug 2019 10:33:26 -0400 Subject: [PATCH] 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: Manasi Navare Reviewed-by: Lyude Paul Reviewed-by: Harry Wentland Signed-off-by: David Francis Signed-off-by: Mikita Lipski Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 +- drivers/gpu/drm/drm_dp_mst_topology.c | 12 +++++++++++- drivers/gpu/drm/i915/display/intel_dp_mst.c | 3 ++- drivers/gpu/drm/nouveau/dispnv50/disp.c | 2 +- drivers/gpu/drm/radeon/radeon_dp_mst.c | 2 +- drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c | 12 ++++++++---- include/drm/drm_dp_mst_helper.h | 3 +-- 7 files changed, 25 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index c4a0d0e5050a..abc359a20a18 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -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, diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index e68d23043973..2443532341d0 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -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); } diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c index 03d1cba0b696..92be17711287 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c @@ -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); diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c index 63425e246018..d0b8ebb3dfe2 100644 --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c @@ -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, diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c index ee28f5b3785e..28eef9282874 100644 --- a/drivers/gpu/drm/radeon/radeon_dp_mst.c +++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c @@ -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", diff --git a/drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c b/drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c index af2b2de65316..bd990d178765 100644 --- a/drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c +++ b/drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c @@ -18,15 +18,19 @@ int igt_dp_mst_calc_pbn_mode(void *ignored) int rate; int bpp; int expected; + bool dsc; } test_params[] = { - { 154000, 30, 689 }, - { 234000, 30, 1047 }, - { 297000, 24, 1063 }, + { 154000, 30, 689, false }, + { 234000, 30, 1047, false }, + { 297000, 24, 1063, false }, + { 332880, 24, 50, true }, + { 324540, 24, 49, true }, }; for (i = 0; i < ARRAY_SIZE(test_params); i++) { pbn = drm_dp_calc_pbn_mode(test_params[i].rate, - test_params[i].bpp); + test_params[i].bpp, + test_params[i].dsc); FAIL(pbn != test_params[i].expected, "Expected PBN %d for clock %d bpp %d, got %d\n", test_params[i].expected, test_params[i].rate, diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h index 5699493c6fb1..0c59c9a348bd 100644 --- a/include/drm/drm_dp_mst_helper.h +++ b/include/drm/drm_dp_mst_helper.h @@ -727,8 +727,7 @@ bool drm_dp_mst_port_has_audio(struct drm_dp_mst_topology_mgr *mgr, struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port); -int drm_dp_calc_pbn_mode(int clock, int bpp); - +int drm_dp_calc_pbn_mode(int clock, int bpp, bool dsc); bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int slots); -- 2.30.2