https://bugs.freedesktop.org/show_bug.cgi?id=105880
--- Comment #12 from Chí-Thanh Christopher Nguyễn chithanh@gentoo.org --- So, with the additional dmesg output from kernel 4.15, the following appeared interesting:
[ 43.356569] [drm] DC: create_links: connectors_num: physical:3, virtual:0 [ 43.356583] [drm] Unsupported Connector type:14! [ 43.356588] [drm] Connector[1] description:signal 4 [ 43.356617] [drm] Unsupported Connector type:5!
If I understand drivers/gpu/drm/amd/dal/dc/core/dc_link.c correctly, the following connector types are supported in construct()
CONNECTOR_ID_HDMI_TYPE_A CONNECTOR_ID_SINGLE_LINK_DVID CONNECTOR_ID_SINGLE_LINK_DVII CONNECTOR_ID_DUAL_LINK_DVID CONNECTOR_ID_DUAL_LINK_DVII CONNECTOR_ID_DISPLAY_PORT CONNECTOR_ID_EDP
else the following code will print the above error message
dal_logger_write(dc_ctx->logger, LOG_MAJOR_WARNING, LOG_MINOR_TM_LINK_SRV, "Unsupported Connector type:%d!\n", link->link_id.id);
According to display/include/grph_object_id.h
CONNECTOR_ID_VGA = 5 CONNECTOR_ID_LVDS = 14
which would explain why no working connectors are found. I will try to find an HDMI monitor to see if it lights up with amdgpu DC.