Handle 128b/132b SST in intel_dp_mtp_tu_compute_config(). The remote
bandwidth overhead and time slot allocation are only relevant for MST;
SST only needs the local bandwidth and a check that 64 slots isn't
exceeded.
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_dp_mst.c | 109 +++++++++++---------
1 file changed, 61 insertions(+), 48 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index d08824d2fefe..3fbf9163272b 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -257,10 +257,7 @@ int intel_dp_mtp_tu_compute_config(struct intel_dp *intel_dp,
for (bpp = max_bpp; bpp >= min_bpp; bpp -= step) {
int local_bw_overhead;
- int remote_bw_overhead;
int link_bpp_x16;
- int remote_tu;
- fixed20_12 pbn;
drm_dbg_kms(display->drm, "Trying bpp %d\n", bpp);
@@ -269,57 +266,73 @@ int intel_dp_mtp_tu_compute_config(struct intel_dp *intel_dp,
local_bw_overhead = intel_dp_mst_bw_overhead(crtc_state,
false, dsc_slice_count, link_bpp_x16);
- remote_bw_overhead = intel_dp_mst_bw_overhead(crtc_state,
- true, dsc_slice_count, link_bpp_x16);
-
intel_dp_mst_compute_m_n(crtc_state,
local_bw_overhead,
link_bpp_x16,
&crtc_state->dp_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
- * the payload size programmed to the first downstream branch
- * device's payload table.
- *
- * Note that atm the payload's PBN value DRM core sends via
- * the ALLOCATE_PAYLOAD side-band message matches the payload
- * size (which it calculates from the PBN value) it programs
- * to the first branch device's payload table. The allocation
- * in the payload table could be reduced though (to
- * crtc_state->dp_m_n.tu), provided that the driver doesn't
- * enable SSC on the corresponding link.
- */
- pbn.full = dfixed_const(intel_dp_mst_calc_pbn(adjusted_mode->crtc_clock,
- link_bpp_x16,
- remote_bw_overhead));
- remote_tu = DIV_ROUND_UP(pbn.full, pbn_div.full);
-
- /*
- * Aligning the TUs ensures that symbols consisting of multiple
- * (4) symbol cycles don't get split between two consecutive
- * MTPs, as required by Bspec.
- * TODO: remove the alignment restriction for 128b/132b links
- * on some platforms, where Bspec allows this.
- */
- remote_tu = ALIGN(remote_tu, 4 / crtc_state->lane_count);
-
- /*
- * Also align PBNs accordingly, since MST core will derive its
- * own copy of TU from the PBN in drm_dp_atomic_find_time_slots().
- * The above comment about the difference between the PBN
- * allocated for the whole path and the TUs allocated for the
- * first branch device's link also applies here.
- */
- pbn.full = remote_tu * pbn_div.full;
-
- drm_WARN_ON(display->drm, remote_tu < crtc_state->dp_m_n.tu);
- crtc_state->dp_m_n.tu = remote_tu;
+ if (intel_dp->is_mst) {
+ int remote_bw_overhead;
+ int remote_tu;
+ fixed20_12 pbn;
+
+ remote_bw_overhead = intel_dp_mst_bw_overhead(crtc_state,
+ true, dsc_slice_count, link_bpp_x16);
+
+ /*
+ * The TU size programmed to the HW determines which slots in
+ * an MTP frame are used for this stream, which needs to match
+ * the payload size programmed to the first downstream branch
+ * device's payload table.
+ *
+ * Note that atm the payload's PBN value DRM core sends via
+ * the ALLOCATE_PAYLOAD side-band message matches the payload
+ * size (which it calculates from the PBN value) it programs
+ * to the first branch device's payload table. The allocation
+ * in the payload table could be reduced though (to
+ * crtc_state->dp_m_n.tu), provided that the driver doesn't
+ * enable SSC on the corresponding link.
+ */
+ pbn.full = dfixed_const(intel_dp_mst_calc_pbn(adjusted_mode->crtc_clock,
+ link_bpp_x16,
+ remote_bw_overhead));
+ remote_tu = DIV_ROUND_UP(pbn.full, pbn_div.full);
+
+ /*
+ * Aligning the TUs ensures that symbols consisting of multiple
+ * (4) symbol cycles don't get split between two consecutive
+ * MTPs, as required by Bspec.
+ * TODO: remove the alignment restriction for 128b/132b links
+ * on some platforms, where Bspec allows this.
+ */
+ remote_tu = ALIGN(remote_tu, 4 / crtc_state->lane_count);
+
+ /*
+ * Also align PBNs accordingly, since MST core will derive its
+ * own copy of TU from the PBN in drm_dp_atomic_find_time_slots().
+ * The above comment about the difference between the PBN
+ * allocated for the whole path and the TUs allocated for the
+ * first branch device's link also applies here.
+ */
+ pbn.full = remote_tu * pbn_div.full;
+
+ drm_WARN_ON(display->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,
+ dfixed_trunc(pbn));
+ } else {
+ /* Same as above for remote_tu */
+ crtc_state->dp_m_n.tu = ALIGN(crtc_state->dp_m_n.tu,
+ 4 / crtc_state->lane_count);
+
+ if (crtc_state->dp_m_n.tu <= 64)
+ slots = crtc_state->dp_m_n.tu;
+ else
+ slots = -EINVAL;
+ }
- slots = drm_dp_atomic_find_time_slots(state, &intel_dp->mst_mgr,
- connector->port,
- dfixed_trunc(pbn));
if (slots == -EDEADLK)
return slots;
--
2.39.5
