From: Hersen Wu <hersenxs.wu@xxxxxxx>
[Why] Mode pbn is not calculated correctly because timing pixel encoding is
not checked within convert_dc_color_depth_into_bpc.
[How] Get mode kbps from dc_bandwidth_in_kbps_from_timing, then calculate
pbn by kbps_to_peak_pbn.
Reviewed-by: Wayne Lin <wayne.lin@xxxxxxx>
Acked-by: Roman Li <roman.li@xxxxxxx>
Signed-off-by: Hersen Wu <hersenxs.wu@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
---
.../display/amdgpu_dm/amdgpu_dm_mst_types.c | 35 ++++++++++++++++---
1 file changed, 30 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
index 941e96f100f4..ad3170b72a47 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
@@ -1601,7 +1601,7 @@ enum dc_status dm_dp_mst_is_port_support_mode(
struct amdgpu_dm_connector *aconnector,
struct dc_stream_state *stream)
{
- int bpp, pbn, branch_max_throughput_mps = 0;
+ int pbn, branch_max_throughput_mps = 0;
struct dc_link_settings cur_link_settings;
unsigned int end_to_end_bw_in_kbps = 0;
unsigned int upper_link_bw_in_kbps = 0, down_link_bw_in_kbps = 0;
@@ -1651,11 +1651,36 @@ enum dc_status dm_dp_mst_is_port_support_mode(
}
}
} else {
- /* check if mode could be supported within full_pbn */
- bpp = convert_dc_color_depth_into_bpc(stream->timing.display_color_depth) * 3;
- pbn = drm_dp_calc_pbn_mode(stream->timing.pix_clk_100hz / 10, bpp << 4);
- if (pbn > aconnector->mst_output_port->full_pbn)
+ /* Check if mode could be supported within max slot
+ * number of current mst link and full_pbn of mst links.
+ */
+ int pbn_div, slot_num, max_slot_num;
+ enum dc_link_encoding_format link_encoding;
+ uint16_t fec_overhead_multiplier_x1000 =
+ get_fec_overhead_multiplier(stream->link);
+ uint32_t stream_kbps =
+ dc_bandwidth_in_kbps_from_timing(&stream->timing,
+ dc_link_get_highest_encoding_format(stream->link));
+
+ pbn = kbps_to_peak_pbn(stream_kbps, fec_overhead_multiplier_x1000);
+ pbn_div = dm_mst_get_pbn_divider(stream->link);
+ slot_num = DIV_ROUND_UP(pbn, pbn_div);
+
+ link_encoding = dc_link_get_highest_encoding_format(stream->link);
+ if (link_encoding == DC_LINK_ENCODING_DP_8b_10b)
+ max_slot_num = 63;
+ else if (link_encoding == DC_LINK_ENCODING_DP_128b_132b)
+ max_slot_num = 64;
+ else {
+ DRM_DEBUG_DRIVER("Invalid link encoding format\n");
return DC_FAIL_BANDWIDTH_VALIDATE;
+ }
+
+ if (slot_num > max_slot_num ||
+ pbn > aconnector->mst_output_port->full_pbn) {
+ DRM_DEBUG_DRIVER("Mode can not be supported within mst links!");
+ return DC_FAIL_BANDWIDTH_VALIDATE;
+ }
}
/* check is mst dsc output bandwidth branch_overall_throughput_0_mps */
--
2.34.1
