diff options
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_dp.c | 19 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_dp.h | 2 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_dp_mst.c | 33 |
3 files changed, 44 insertions, 10 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index d58acc36e3be..e7502a824047 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -355,6 +355,9 @@ int intel_dp_max_lane_count(struct intel_dp *intel_dp) /* * The required data bandwidth for a mode with given pixel clock and bpp. This * is the required net bandwidth independent of the data bandwidth efficiency. + * + * TODO: check if callers of this functions should use + * intel_dp_effective_data_rate() instead. */ int intel_dp_link_required(int pixel_clock, int bpp) @@ -363,6 +366,22 @@ intel_dp_link_required(int pixel_clock, int bpp) return DIV_ROUND_UP(pixel_clock * bpp, 8); } +/** + * intel_dp_effective_data_rate - Return the pixel data rate accounting for BW allocation overhead + * @pixel_clock: pixel clock in kHz + * @bpp_x16: bits per pixel .4 fixed point format + * @bw_overhead: BW allocation overhead in 1ppm units + * + * Return the effective pixel data rate in kB/sec units taking into account + * the provided SSC, FEC, DSC BW allocation overhead. + */ +int intel_dp_effective_data_rate(int pixel_clock, int bpp_x16, + int bw_overhead) +{ + return DIV_ROUND_UP_ULL(mul_u32_u32(pixel_clock * bpp_x16, bw_overhead), + 1000000 * 16 * 8); +} + /* * Given a link rate and lanes, get the data bandwidth. * diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h index 777aa858f899..05db46b111f2 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.h +++ b/drivers/gpu/drm/i915/display/intel_dp.h @@ -103,6 +103,8 @@ bool intel_dp_source_supports_tps4(struct drm_i915_private *i915); bool intel_dp_get_colorimetry_status(struct intel_dp *intel_dp); int intel_dp_link_required(int pixel_clock, int bpp); +int intel_dp_effective_data_rate(int pixel_clock, int bpp_x16, + int bw_overhead); int intel_dp_max_data_rate(int max_link_rate, int max_lanes); bool intel_dp_can_bigjoiner(struct intel_dp *intel_dp); bool intel_dp_needs_vsc_sdp(const struct intel_crtc_state *crtc_state, diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c index a5ddd1781969..d3d53e1b4489 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c @@ -115,6 +115,7 @@ static void intel_dp_mst_compute_m_n(const struct intel_crtc_state *crtc_state, const struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode; + /* TODO: Check WA 14013163432 to set data M/N for full BW utilization. */ intel_link_compute_m_n(bpp_x16, crtc_state->lane_count, adjusted_mode->crtc_clock, crtc_state->port_clock, @@ -124,6 +125,18 @@ static void intel_dp_mst_compute_m_n(const struct intel_crtc_state *crtc_state, m_n->tu = DIV_ROUND_UP_ULL(mul_u32_u32(m_n->data_m, 64), m_n->data_n); } +static int intel_dp_mst_calc_pbn(int pixel_clock, int bpp_x16, int bw_overhead) +{ + int effective_data_rate = + intel_dp_effective_data_rate(pixel_clock, bpp_x16, bw_overhead); + + /* + * TODO: Use drm_dp_calc_pbn_mode() instead, once it's converted + * to calculate PBN with the BW overhead passed to it. + */ + return DIV_ROUND_UP(effective_data_rate * 64, 54 * 1000); +} + static int intel_dp_mst_find_vcpi_slots_for_bpp(struct intel_encoder *encoder, struct intel_crtc_state *crtc_state, int max_bpp, @@ -167,10 +180,10 @@ static int intel_dp_mst_find_vcpi_slots_for_bpp(struct intel_encoder *encoder, min_bpp, max_bpp); for (bpp = max_bpp; bpp >= min_bpp; bpp -= step) { - struct intel_link_m_n remote_m_n; int local_bw_overhead; int remote_bw_overhead; int link_bpp_x16; + int remote_tu; drm_dbg_kms(&i915->drm, "Trying bpp %d\n", bpp); @@ -191,11 +204,6 @@ static int intel_dp_mst_find_vcpi_slots_for_bpp(struct intel_encoder *encoder, link_bpp_x16, &crtc_state->dp_m_n); - intel_dp_mst_compute_m_n(crtc_state, connector, - remote_bw_overhead, - link_bpp_x16, - &remote_m_n); - /* * The TU size programmed to the HW determines which slots in * an MTP frame are used for this stream, which needs to match @@ -210,9 +218,14 @@ static int intel_dp_mst_find_vcpi_slots_for_bpp(struct intel_encoder *encoder, * crtc_state->dp_m_n.tu), provided that the driver doesn't * enable SSC on the corresponding link. */ - drm_WARN_ON(&i915->drm, remote_m_n.tu < crtc_state->dp_m_n.tu); - crtc_state->dp_m_n.tu = remote_m_n.tu; - crtc_state->pbn = remote_m_n.tu * dfixed_trunc(mst_state->pbn_div); + crtc_state->pbn = intel_dp_mst_calc_pbn(adjusted_mode->crtc_clock, + link_bpp_x16, + remote_bw_overhead); + + remote_tu = DIV_ROUND_UP(dfixed_const(crtc_state->pbn), mst_state->pbn_div.full); + + drm_WARN_ON(&i915->drm, remote_tu < crtc_state->dp_m_n.tu); + crtc_state->dp_m_n.tu = remote_tu; slots = drm_dp_atomic_find_time_slots(state, &intel_dp->mst_mgr, connector->port, @@ -221,7 +234,7 @@ static int intel_dp_mst_find_vcpi_slots_for_bpp(struct intel_encoder *encoder, return slots; if (slots >= 0) { - drm_WARN_ON(&i915->drm, slots != remote_m_n.tu); + drm_WARN_ON(&i915->drm, slots != crtc_state->dp_m_n.tu); break; } |