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path: root/drivers/gpu/drm/amd/display/dc/link/link_detection.c
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Diffstat (limited to 'drivers/gpu/drm/amd/display/dc/link/link_detection.c')
-rw-r--r--drivers/gpu/drm/amd/display/dc/link/link_detection.c211
1 files changed, 191 insertions, 20 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/link/link_detection.c b/drivers/gpu/drm/amd/display/dc/link/link_detection.c
index e026c728042a..6d31f4967f1a 100644
--- a/drivers/gpu/drm/amd/display/dc/link/link_detection.c
+++ b/drivers/gpu/drm/amd/display/dc/link/link_detection.c
@@ -270,6 +270,10 @@ static void read_scdc_caps(struct ddc_service *ddc_service,
uint8_t slave_address = HDMI_SCDC_ADDRESS;
uint8_t offset = HDMI_SCDC_MANUFACTURER_OUI;
+ if (ddc_service->link->local_sink &&
+ !ddc_service->link->local_sink->edid_caps.scdc_present)
+ return;
+
link_query_ddc_data(ddc_service, slave_address, &offset,
sizeof(offset), sink->scdc_caps.manufacturer_OUI.byte,
sizeof(sink->scdc_caps.manufacturer_OUI.byte));
@@ -593,8 +597,9 @@ static bool detect_dp(struct dc_link *link,
if (sink_caps->transaction_type == DDC_TRANSACTION_TYPE_I2C_OVER_AUX) {
sink_caps->signal = SIGNAL_TYPE_DISPLAY_PORT;
- if (!detect_dp_sink_caps(link))
+ if (!detect_dp_sink_caps(link)) {
return false;
+ }
if (is_dp_branch_device(link))
/* DP SST branch */
@@ -611,6 +616,7 @@ static bool detect_dp(struct dc_link *link,
link->dpcd_caps.dongle_type = sink_caps->dongle_type;
link->dpcd_caps.is_dongle_type_one = sink_caps->is_dongle_type_one;
link->dpcd_caps.dpcd_rev.raw = 0;
+ link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.raw = 0;
}
return true;
@@ -654,7 +660,7 @@ static bool wait_for_entering_dp_alt_mode(struct dc_link *link)
return true;
is_in_alt_mode = link->link_enc->funcs->is_in_alt_mode(link->link_enc);
- DC_LOG_DC("DP Alt mode state on HPD: %d\n", is_in_alt_mode);
+ DC_LOG_DC("DP Alt mode state on HPD: %d Link=%d\n", is_in_alt_mode, link->link_index);
if (is_in_alt_mode)
return true;
@@ -816,7 +822,10 @@ static bool should_verify_link_capability_destructively(struct dc_link *link,
{
bool destrictive = false;
struct dc_link_settings max_link_cap;
- bool is_link_enc_unavailable = link->link_enc &&
+ bool is_link_enc_unavailable = false;
+
+ if (!link->dc->config.unify_link_enc_assignment)
+ is_link_enc_unavailable = link->link_enc &&
link->dc->res_pool->funcs->link_encs_assign &&
!link_enc_cfg_is_link_enc_avail(
link->ctx->dc,
@@ -829,7 +838,8 @@ static bool should_verify_link_capability_destructively(struct dc_link *link,
if (link->dc->debug.skip_detection_link_training ||
dc_is_embedded_signal(link->local_sink->sink_signal) ||
- link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA) {
+ (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA &&
+ !link->dc->config.enable_dpia_pre_training)) {
destrictive = false;
} else if (link_dp_get_encoding_format(&max_link_cap) ==
DP_8b_10b_ENCODING) {
@@ -852,6 +862,94 @@ static void verify_link_capability(struct dc_link *link, struct dc_sink *sink,
verify_link_capability_non_destructive(link);
}
+/**
+ * link_detect_evaluate_edid_header() - Evaluate if an EDID header is acceptable.
+ *
+ * Evaluates an 8-byte EDID header to check if it's good enough
+ * for the purpose of determining whether a display is connected
+ * without reading the full EDID.
+ *
+ * @edid_header: The first 8 bytes of the EDID read from DDC.
+ *
+ * Return: true if the header looks valid (>= 6 of 8 bytes match the
+ * expected 00/FF pattern), false otherwise.
+ */
+static bool link_detect_evaluate_edid_header(uint8_t edid_header[8])
+{
+ int edid_header_score = 0;
+ int i;
+
+ for (i = 0; i < 8; ++i)
+ edid_header_score += edid_header[i] == ((i == 0 || i == 7) ? 0x00 : 0xff);
+
+ return edid_header_score >= 6;
+}
+
+/**
+ * link_detect_ddc_probe() - Probe the DDC to see if a display is connected.
+ *
+ * Detect whether a display is connected to DDC without reading full EDID.
+ * Reads only the EDID header (the first 8 bytes of EDID) from DDC and
+ * evaluates whether that matches.
+ *
+ * @link: DC link whose DDC/I2C is probed for the EDID header.
+ *
+ * Return: true if the EDID header was read and passes validation,
+ * false otherwise.
+ */
+static bool link_detect_ddc_probe(struct dc_link *link)
+{
+ if (!link->ddc)
+ return false;
+
+ uint8_t edid_header[8] = {0};
+ bool ddc_probed = i2c_read(link->ddc, 0x50, edid_header, sizeof(edid_header));
+
+ if (!ddc_probed)
+ return false;
+
+ if (!link_detect_evaluate_edid_header(edid_header))
+ return false;
+
+ return true;
+}
+
+/**
+ * link_detect_dac_load_detect() - Performs DAC load detection.
+ *
+ * Load detection can be used to detect the presence of an
+ * analog display when we can't read DDC. This causes a visible
+ * visual glitch so it should be used sparingly.
+ *
+ * @link: DC link to test using the DAC load-detect path.
+ *
+ * Return: true if the VBIOS load-detect call reports OK, false
+ * otherwise.
+ */
+static bool link_detect_dac_load_detect(struct dc_link *link)
+{
+ struct dc_bios *bios = link->ctx->dc_bios;
+ struct link_encoder *link_enc = link->link_enc;
+ enum engine_id engine_id = link_enc->preferred_engine;
+ enum dal_device_type device_type = DEVICE_TYPE_CRT;
+ enum bp_result bp_result;
+ uint32_t enum_id;
+
+ switch (engine_id) {
+ case ENGINE_ID_DACB:
+ enum_id = 2;
+ break;
+ case ENGINE_ID_DACA:
+ default:
+ engine_id = ENGINE_ID_DACA;
+ enum_id = 1;
+ break;
+ }
+
+ bp_result = bios->funcs->dac_load_detection(bios, engine_id, device_type, enum_id);
+ return bp_result == BP_RESULT_OK;
+}
+
/*
* detect_link_and_local_sink() - Detect if a sink is attached to a given link
*
@@ -936,6 +1034,12 @@ static bool detect_link_and_local_sink(struct dc_link *link,
break;
}
+ case SIGNAL_TYPE_RGB: {
+ sink_caps.transaction_type = DDC_TRANSACTION_TYPE_I2C;
+ sink_caps.signal = SIGNAL_TYPE_RGB;
+ break;
+ }
+
case SIGNAL_TYPE_LVDS: {
sink_caps.transaction_type = DDC_TRANSACTION_TYPE_I2C;
sink_caps.signal = SIGNAL_TYPE_LVDS;
@@ -1003,21 +1107,11 @@ static bool detect_link_and_local_sink(struct dc_link *link,
link->reported_link_cap.link_rate > LINK_RATE_HIGH3)
link->reported_link_cap.link_rate = LINK_RATE_HIGH3;
- /*
- * If this is DP over USB4 link then we need to:
- * - Enable BW ALLOC support on DPtx if applicable
- */
- if (dc->config.usb4_bw_alloc_support) {
- if (link_dp_dpia_set_dptx_usb4_bw_alloc_support(link)) {
- /* update with non reduced link cap if bw allocation mode is supported */
- if (link->dpia_bw_alloc_config.nrd_max_link_rate &&
- link->dpia_bw_alloc_config.nrd_max_lane_count) {
- link->reported_link_cap.link_rate =
- link->dpia_bw_alloc_config.nrd_max_link_rate;
- link->reported_link_cap.lane_count =
- link->dpia_bw_alloc_config.nrd_max_lane_count;
- }
- }
+ if (link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dp_tunneling
+ && link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dpia_bw_alloc
+ && link->dpcd_caps.usb4_dp_tun_info.driver_bw_cap.bits.driver_bw_alloc_support) {
+ if (link_dpia_enable_usb4_dp_bw_alloc_mode(link) == false)
+ link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dpia_bw_alloc = false;
}
break;
}
@@ -1070,7 +1164,30 @@ static bool detect_link_and_local_sink(struct dc_link *link,
DC_LOG_ERROR("Partial EDID valid, abandon invalid blocks.\n");
break;
case EDID_NO_RESPONSE:
+ /* Analog connectors without EDID:
+ * - old monitor that actually doesn't have EDID
+ * - cheap DVI-A cable or adapter that doesn't connect DDC
+ */
+ if (dc_connector_supports_analog(link->link_id.id)) {
+ /* If we didn't do DAC load detection yet, do it now
+ * to verify there really is a display connected.
+ */
+ if (link->type != dc_connection_dac_load &&
+ !link_detect_dac_load_detect(link)) {
+ if (prev_sink)
+ dc_sink_release(prev_sink);
+ link_disconnect_sink(link);
+ return false;
+ }
+
+ DC_LOG_INFO("%s detected analog display without EDID\n", __func__);
+ link->type = dc_connection_dac_load;
+ sink->edid_caps.analog = true;
+ break;
+ }
+
DC_LOG_ERROR("No EDID read.\n");
+
/*
* Abort detection for non-DP connectors if we have
* no EDID
@@ -1137,13 +1254,26 @@ static bool detect_link_and_local_sink(struct dc_link *link,
sink = prev_sink;
prev_sink = NULL;
}
- query_hdcp_capability(sink->sink_signal, link);
+
+ if (!sink->edid_caps.analog)
+ query_hdcp_capability(sink->sink_signal, link);
}
+ /* DVI-I connector connected to analog display. */
+ if ((link->link_id.id == CONNECTOR_ID_DUAL_LINK_DVII ||
+ link->link_id.id == CONNECTOR_ID_SINGLE_LINK_DVII) &&
+ sink->edid_caps.analog)
+ sink->sink_signal = SIGNAL_TYPE_RGB;
+
/* HDMI-DVI Dongle */
if (sink->sink_signal == SIGNAL_TYPE_HDMI_TYPE_A &&
!sink->edid_caps.edid_hdmi)
sink->sink_signal = SIGNAL_TYPE_DVI_SINGLE_LINK;
+ else if (dc_is_dvi_signal(sink->sink_signal) &&
+ dc_is_dvi_signal(link->connector_signal) &&
+ aud_support->hdmi_audio_native &&
+ sink->edid_caps.edid_hdmi)
+ sink->sink_signal = SIGNAL_TYPE_HDMI_TYPE_A;
if (link->local_sink && dc_is_dp_signal(sink_caps.signal))
dp_trace_init(link);
@@ -1232,6 +1362,36 @@ static bool detect_link_and_local_sink(struct dc_link *link,
return true;
}
+/**
+ * link_detect_analog() - Determines if an analog sink is connected.
+ *
+ * @link: DC link to evaluate (must support analog signalling).
+ * @type: Updated with the detected connection type:
+ * dc_connection_single (analog via DDC),
+ * dc_connection_dac_load (via load-detect),
+ * or dc_connection_none.
+ *
+ * Return: true if detection completed.
+ */
+static bool link_detect_analog(struct dc_link *link, enum dc_connection_type *type)
+{
+ /* Don't care about connectors that don't support an analog signal. */
+ ASSERT(dc_connector_supports_analog(link->link_id.id));
+
+ if (link_detect_ddc_probe(link)) {
+ *type = dc_connection_single;
+ return true;
+ }
+
+ if (link_detect_dac_load_detect(link)) {
+ *type = dc_connection_dac_load;
+ return true;
+ }
+
+ *type = dc_connection_none;
+ return true;
+}
+
/*
* link_detect_connection_type() - Determine if there is a sink connected
*
@@ -1248,6 +1408,17 @@ bool link_detect_connection_type(struct dc_link *link, enum dc_connection_type *
return true;
}
+ /* Ignore the HPD pin (if any) for analog connectors.
+ * Instead rely on DDC and DAC.
+ *
+ * - VGA connectors don't have any HPD at all.
+ * - Some DVI-A cables don't connect the HPD pin.
+ * - Some DVI-A cables pull up the HPD pin.
+ * (So it's high even when no display is connected.)
+ */
+ if (dc_connector_supports_analog(link->link_id.id))
+ return link_detect_analog(link, type);
+
if (link->connector_signal == SIGNAL_TYPE_EDP) {
/*in case it is not on*/
if (!link->dc->config.edp_no_power_sequencing)