link_status[3], link_status[4], link_status[5]);
}
+static int intel_dp_lttpr_count(struct intel_dp *intel_dp)
+{
+ int count = drm_dp_lttpr_count(intel_dp->lttpr_common_caps);
+
+ /*
+ * Pretend no LTTPRs in case of LTTPR detection error, or
+ * if too many (>8) LTTPRs are detected. This translates to link
+ * training in transparent mode.
+ */
+ return count <= 0 ? 0 : count;
+}
+
+static void intel_dp_reset_lttpr_count(struct intel_dp *intel_dp)
+{
+ intel_dp->lttpr_common_caps[DP_PHY_REPEATER_CNT -
+ DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV] = 0;
+}
+
+static const char *intel_dp_phy_name(enum drm_dp_phy dp_phy,
+ char *buf, size_t buf_size)
+{
+ if (dp_phy == DP_PHY_DPRX)
+ snprintf(buf, buf_size, "DPRX");
+ else
+ snprintf(buf, buf_size, "LTTPR %d", dp_phy - DP_PHY_LTTPR1 + 1);
+
+ return buf;
+}
+
+static u8 *intel_dp_lttpr_phy_caps(struct intel_dp *intel_dp,
+ enum drm_dp_phy dp_phy)
+{
+ return intel_dp->lttpr_phy_caps[dp_phy - DP_PHY_LTTPR1];
+}
+
+static void intel_dp_read_lttpr_phy_caps(struct intel_dp *intel_dp,
+ enum drm_dp_phy dp_phy)
+{
+ u8 *phy_caps = intel_dp_lttpr_phy_caps(intel_dp, dp_phy);
+ char phy_name[10];
+
+ intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name));
+
+ if (drm_dp_read_lttpr_phy_caps(&intel_dp->aux, dp_phy, phy_caps) < 0) {
+ drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
+ "failed to read the PHY caps for %s\n",
+ phy_name);
+ return;
+ }
+
+ drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
+ "%s PHY capabilities: %*ph\n",
+ phy_name,
+ (int)sizeof(intel_dp->lttpr_phy_caps[0]),
+ phy_caps);
+}
+
static bool intel_dp_read_lttpr_common_caps(struct intel_dp *intel_dp)
{
if (drm_dp_read_lttpr_common_caps(&intel_dp->aux,
* intel_dp_lttpr_init - detect LTTPRs and init the LTTPR link training mode
* @intel_dp: Intel DP struct
*
- * Read the LTTPR common capabilities and switch to transparent link training
- * mode.
+ * Read the LTTPR common capabilities, switch to non-transparent link training
+ * mode if any is detected and read the PHY capabilities for all detected
+ * LTTPRs. In case of an LTTPR detection error or if the number of
+ * LTTPRs is more than is supported (8), fall back to the no-LTTPR,
+ * transparent mode link training mode.
+ *
+ * Returns:
+ * >0 if LTTPRs were detected and the non-transparent LT mode was set
+ * 0 if no LTTPRs or more than 8 LTTPRs were detected or in case of a
+ * detection failure and the transparent LT mode was set
*/
int intel_dp_lttpr_init(struct intel_dp *intel_dp)
{
+ int lttpr_count;
+ bool ret;
+ int i;
+
if (intel_dp_is_edp(intel_dp))
return 0;
- intel_dp_read_lttpr_common_caps(intel_dp);
+ ret = intel_dp_read_lttpr_common_caps(intel_dp);
/*
* See DP Standard v2.0 3.6.6.1. about the explicit disabling of
- * non-transparent mode.
+ * non-transparent mode and the disable->enable non-transparent mode
+ * sequence.
*/
intel_dp_set_lttpr_transparent_mode(intel_dp, true);
- return 0;
+ if (!ret)
+ return 0;
+
+ lttpr_count = intel_dp_lttpr_count(intel_dp);
+
+ /*
+ * In case of unsupported number of LTTPRs or failing to switch to
+ * non-transparent mode fall-back to transparent link training mode,
+ * still taking into account any LTTPR common lane- rate/count limits.
+ */
+ if (lttpr_count == 0)
+ return 0;
+
+ if (!intel_dp_set_lttpr_transparent_mode(intel_dp, false)) {
+ drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
+ "Switching to LTTPR non-transparent LT mode failed, fall-back to transparent mode\n");
+
+ intel_dp_set_lttpr_transparent_mode(intel_dp, true);
+ intel_dp_reset_lttpr_count(intel_dp);
+
+ return 0;
+ }
+
+ for (i = 0; i < lttpr_count; i++)
+ intel_dp_read_lttpr_phy_caps(intel_dp, DP_PHY_LTTPR(i));
+
+ return lttpr_count;
}
+EXPORT_SYMBOL(intel_dp_lttpr_init);
static u8 dp_voltage_max(u8 preemph)
{
}
}
+static u8 intel_dp_lttpr_voltage_max(struct intel_dp *intel_dp,
+ enum drm_dp_phy dp_phy)
+{
+ const u8 *phy_caps = intel_dp_lttpr_phy_caps(intel_dp, dp_phy);
+
+ if (drm_dp_lttpr_voltage_swing_level_3_supported(phy_caps))
+ return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
+ else
+ return DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
+}
+
+static u8 intel_dp_lttpr_preemph_max(struct intel_dp *intel_dp,
+ enum drm_dp_phy dp_phy)
+{
+ const u8 *phy_caps = intel_dp_lttpr_phy_caps(intel_dp, dp_phy);
+
+ if (drm_dp_lttpr_pre_emphasis_level_3_supported(phy_caps))
+ return DP_TRAIN_PRE_EMPH_LEVEL_3;
+ else
+ return DP_TRAIN_PRE_EMPH_LEVEL_2;
+}
+
+static bool
+intel_dp_phy_is_downstream_of_source(struct intel_dp *intel_dp,
+ enum drm_dp_phy dp_phy)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ int lttpr_count = intel_dp_lttpr_count(intel_dp);
+
+ drm_WARN_ON_ONCE(&i915->drm, lttpr_count == 0 && dp_phy != DP_PHY_DPRX);
+
+ return lttpr_count == 0 || dp_phy == DP_PHY_LTTPR(lttpr_count - 1);
+}
+
+static u8 intel_dp_phy_voltage_max(struct intel_dp *intel_dp,
+ const struct intel_crtc_state *crtc_state,
+ enum drm_dp_phy dp_phy)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ u8 voltage_max;
+
+ /*
+ * Get voltage_max from the DPTX_PHY (source or LTTPR) upstream from
+ * the DPRX_PHY we train.
+ */
+ if (intel_dp_phy_is_downstream_of_source(intel_dp, dp_phy))
+ voltage_max = intel_dp->voltage_max(intel_dp, crtc_state);
+ else
+ voltage_max = intel_dp_lttpr_voltage_max(intel_dp, dp_phy + 1);
+
+ drm_WARN_ON_ONCE(&i915->drm,
+ voltage_max != DP_TRAIN_VOLTAGE_SWING_LEVEL_2 &&
+ voltage_max != DP_TRAIN_VOLTAGE_SWING_LEVEL_3);
+
+ return voltage_max;
+}
+
+static u8 intel_dp_phy_preemph_max(struct intel_dp *intel_dp,
+ enum drm_dp_phy dp_phy)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ u8 preemph_max;
+
+ /*
+ * Get preemph_max from the DPTX_PHY (source or LTTPR) upstream from
+ * the DPRX_PHY we train.
+ */
+ if (intel_dp_phy_is_downstream_of_source(intel_dp, dp_phy))
+ preemph_max = intel_dp->preemph_max(intel_dp);
+ else
+ preemph_max = intel_dp_lttpr_preemph_max(intel_dp, dp_phy + 1);
+
+ drm_WARN_ON_ONCE(&i915->drm,
+ preemph_max != DP_TRAIN_PRE_EMPH_LEVEL_2 &&
+ preemph_max != DP_TRAIN_PRE_EMPH_LEVEL_3);
+
+ return preemph_max;
+}
+
void
intel_dp_get_adjust_train(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state,
+ enum drm_dp_phy dp_phy,
const u8 link_status[DP_LINK_STATUS_SIZE])
{
- struct drm_i915_private *i915 = dp_to_i915(intel_dp);
u8 v = 0;
u8 p = 0;
int lane;
p = max(p, drm_dp_get_adjust_request_pre_emphasis(link_status, lane));
}
- preemph_max = intel_dp->preemph_max(intel_dp);
- drm_WARN_ON_ONCE(&i915->drm,
- preemph_max != DP_TRAIN_PRE_EMPH_LEVEL_2 &&
- preemph_max != DP_TRAIN_PRE_EMPH_LEVEL_3);
-
+ preemph_max = intel_dp_phy_preemph_max(intel_dp, dp_phy);
if (p >= preemph_max)
p = preemph_max | DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
v = min(v, dp_voltage_max(p));
- voltage_max = intel_dp->voltage_max(intel_dp, crtc_state);
- drm_WARN_ON_ONCE(&i915->drm,
- voltage_max != DP_TRAIN_VOLTAGE_SWING_LEVEL_2 &&
- voltage_max != DP_TRAIN_VOLTAGE_SWING_LEVEL_3);
-
+ voltage_max = intel_dp_phy_voltage_max(intel_dp, crtc_state, dp_phy);
if (v >= voltage_max)
v = voltage_max | DP_TRAIN_MAX_SWING_REACHED;
intel_dp->train_set[lane] = v | p;
}
+static int intel_dp_training_pattern_set_reg(struct intel_dp *intel_dp,
+ enum drm_dp_phy dp_phy)
+{
+ return dp_phy == DP_PHY_DPRX ?
+ DP_TRAINING_PATTERN_SET :
+ DP_TRAINING_PATTERN_SET_PHY_REPEATER(dp_phy);
+}
+
static bool
intel_dp_set_link_train(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state,
+ enum drm_dp_phy dp_phy,
u8 dp_train_pat)
{
+ int reg = intel_dp_training_pattern_set_reg(intel_dp, dp_phy);
u8 buf[sizeof(intel_dp->train_set) + 1];
int len;
memcpy(buf + 1, intel_dp->train_set, crtc_state->lane_count);
len = crtc_state->lane_count + 1;
- return drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_PATTERN_SET,
- buf, len) == len;
+ return drm_dp_dpcd_write(&intel_dp->aux, reg, buf, len) == len;
}
static bool
intel_dp_reset_link_train(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state,
+ enum drm_dp_phy dp_phy,
u8 dp_train_pat)
{
memset(intel_dp->train_set, 0, sizeof(intel_dp->train_set));
intel_dp_set_signal_levels(intel_dp, crtc_state);
- return intel_dp_set_link_train(intel_dp, crtc_state, dp_train_pat);
+ return intel_dp_set_link_train(intel_dp, crtc_state, dp_phy, dp_train_pat);
}
static bool
intel_dp_update_link_train(struct intel_dp *intel_dp,
- const struct intel_crtc_state *crtc_state)
+ const struct intel_crtc_state *crtc_state,
+ enum drm_dp_phy dp_phy)
{
+ int reg = dp_phy == DP_PHY_DPRX ?
+ DP_TRAINING_LANE0_SET :
+ DP_TRAINING_LANE0_SET_PHY_REPEATER(dp_phy);
int ret;
intel_dp_set_signal_levels(intel_dp, crtc_state);
- ret = drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_LANE0_SET,
+ ret = drm_dp_dpcd_write(&intel_dp->aux, reg,
intel_dp->train_set, crtc_state->lane_count);
return ret == crtc_state->lane_count;
return true;
}
-/* Perform the link training clock recovery phase using training pattern 1. */
+static void intel_dp_link_training_clock_recovery_delay(struct intel_dp *intel_dp,
+ enum drm_dp_phy dp_phy)
+{
+ if (dp_phy == DP_PHY_DPRX)
+ drm_dp_link_train_clock_recovery_delay(intel_dp->dpcd);
+ else
+ drm_dp_lttpr_link_train_clock_recovery_delay();
+}
+
+/*
+ * Perform the link training clock recovery phase on the given DP PHY using
+ * training pattern 1.
+ */
static bool
intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp,
- const struct intel_crtc_state *crtc_state)
+ const struct intel_crtc_state *crtc_state,
+ enum drm_dp_phy dp_phy)
{
struct drm_i915_private *i915 = dp_to_i915(intel_dp);
u8 voltage;
bool max_vswing_reached = false;
/* clock recovery */
- if (!intel_dp_reset_link_train(intel_dp, crtc_state,
+ if (!intel_dp_reset_link_train(intel_dp, crtc_state, dp_phy,
DP_TRAINING_PATTERN_1 |
DP_LINK_SCRAMBLING_DISABLE)) {
drm_err(&i915->drm, "failed to enable link training\n");
for (cr_tries = 0; cr_tries < max_cr_tries; ++cr_tries) {
u8 link_status[DP_LINK_STATUS_SIZE];
- drm_dp_link_train_clock_recovery_delay(intel_dp->dpcd);
+ intel_dp_link_training_clock_recovery_delay(intel_dp, dp_phy);
- if (!intel_dp_get_link_status(intel_dp, link_status)) {
+ if (drm_dp_dpcd_read_phy_link_status(&intel_dp->aux, dp_phy,
+ link_status) < 0) {
drm_err(&i915->drm, "failed to get link status\n");
return false;
}
voltage = intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
/* Update training set as requested by target */
- intel_dp_get_adjust_train(intel_dp, crtc_state, link_status);
- if (!intel_dp_update_link_train(intel_dp, crtc_state)) {
+ intel_dp_get_adjust_train(intel_dp, crtc_state, dp_phy,
+ link_status);
+ if (!intel_dp_update_link_train(intel_dp, crtc_state, dp_phy)) {
drm_err(&i915->drm,
"failed to update link training\n");
return false;
* or 1.2 devices that support it, Training Pattern 2 otherwise.
*/
static u32 intel_dp_training_pattern(struct intel_dp *intel_dp,
- const struct intel_crtc_state *crtc_state)
+ const struct intel_crtc_state *crtc_state,
+ enum drm_dp_phy dp_phy)
{
bool source_tps3, sink_tps3, source_tps4, sink_tps4;
* for all downstream devices that support HBR3. There are no known eDP
* panels that support TPS4 as of Feb 2018 as per VESA eDP_v1.4b_E1
* specification.
+ * LTTPRs must support TPS4.
*/
source_tps4 = intel_dp_source_supports_hbr3(intel_dp);
- sink_tps4 = drm_dp_tps4_supported(intel_dp->dpcd);
+ sink_tps4 = dp_phy != DP_PHY_DPRX ||
+ drm_dp_tps4_supported(intel_dp->dpcd);
if (source_tps4 && sink_tps4) {
return DP_TRAINING_PATTERN_4;
} else if (crtc_state->port_clock == 810000) {
* all sinks follow the spec.
*/
source_tps3 = intel_dp_source_supports_hbr2(intel_dp);
- sink_tps3 = drm_dp_tps3_supported(intel_dp->dpcd);
+ sink_tps3 = dp_phy != DP_PHY_DPRX ||
+ drm_dp_tps3_supported(intel_dp->dpcd);
if (source_tps3 && sink_tps3) {
return DP_TRAINING_PATTERN_3;
} else if (crtc_state->port_clock >= 540000) {
return DP_TRAINING_PATTERN_2;
}
+static void
+intel_dp_link_training_channel_equalization_delay(struct intel_dp *intel_dp,
+ enum drm_dp_phy dp_phy)
+{
+ if (dp_phy == DP_PHY_DPRX) {
+ drm_dp_link_train_channel_eq_delay(intel_dp->dpcd);
+ } else {
+ const u8 *phy_caps = intel_dp_lttpr_phy_caps(intel_dp, dp_phy);
+
+ drm_dp_lttpr_link_train_channel_eq_delay(phy_caps);
+ }
+}
+
/*
- * Perform the link training channel equalization phase using one of training
- * pattern 2, 3 or 4 depending on the source and sink capabilities.
+ * Perform the link training channel equalization phase on the given DP PHY
+ * using one of training pattern 2, 3 or 4 depending on the source and
+ * sink capabilities.
*/
static bool
intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp,
- const struct intel_crtc_state *crtc_state)
+ const struct intel_crtc_state *crtc_state,
+ enum drm_dp_phy dp_phy)
{
struct drm_i915_private *i915 = dp_to_i915(intel_dp);
int tries;
u8 link_status[DP_LINK_STATUS_SIZE];
bool channel_eq = false;
- training_pattern = intel_dp_training_pattern(intel_dp, crtc_state);
+ training_pattern = intel_dp_training_pattern(intel_dp, crtc_state, dp_phy);
/* Scrambling is disabled for TPS2/3 and enabled for TPS4 */
if (training_pattern != DP_TRAINING_PATTERN_4)
training_pattern |= DP_LINK_SCRAMBLING_DISABLE;
/* channel equalization */
- if (!intel_dp_set_link_train(intel_dp, crtc_state,
+ if (!intel_dp_set_link_train(intel_dp, crtc_state, dp_phy,
training_pattern)) {
drm_err(&i915->drm, "failed to start channel equalization\n");
return false;
}
for (tries = 0; tries < 5; tries++) {
-
- drm_dp_link_train_channel_eq_delay(intel_dp->dpcd);
- if (!intel_dp_get_link_status(intel_dp, link_status)) {
+ intel_dp_link_training_channel_equalization_delay(intel_dp,
+ dp_phy);
+ if (drm_dp_dpcd_read_phy_link_status(&intel_dp->aux, dp_phy,
+ link_status) < 0) {
drm_err(&i915->drm,
"failed to get link status\n");
break;
}
/* Update training set as requested by target */
- intel_dp_get_adjust_train(intel_dp, crtc_state, link_status);
- if (!intel_dp_update_link_train(intel_dp, crtc_state)) {
+ intel_dp_get_adjust_train(intel_dp, crtc_state, dp_phy,
+ link_status);
+ if (!intel_dp_update_link_train(intel_dp, crtc_state, dp_phy)) {
drm_err(&i915->drm,
"failed to update link training\n");
break;
"Channel equalization failed 5 times\n");
}
- if (intel_dp->set_idle_link_train)
- intel_dp->set_idle_link_train(intel_dp, crtc_state);
-
return channel_eq;
}
-static bool intel_dp_disable_dpcd_training_pattern(struct intel_dp *intel_dp)
+static bool intel_dp_disable_dpcd_training_pattern(struct intel_dp *intel_dp,
+ enum drm_dp_phy dp_phy)
{
+ int reg = intel_dp_training_pattern_set_reg(intel_dp, dp_phy);
u8 val = DP_TRAINING_PATTERN_DISABLE;
- return drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_PATTERN_SET, &val, 1) == 1;
+ return drm_dp_dpcd_write(&intel_dp->aux, reg, &val, 1) == 1;
}
/**
intel_dp_program_link_training_pattern(intel_dp,
crtc_state,
DP_TRAINING_PATTERN_DISABLE);
- intel_dp_disable_dpcd_training_pattern(intel_dp);
+ intel_dp_disable_dpcd_training_pattern(intel_dp, DP_PHY_DPRX);
}
static bool
-intel_dp_link_train(struct intel_dp *intel_dp,
- const struct intel_crtc_state *crtc_state)
+intel_dp_link_train_phy(struct intel_dp *intel_dp,
+ const struct intel_crtc_state *crtc_state,
+ enum drm_dp_phy dp_phy)
{
struct intel_connector *intel_connector = intel_dp->attached_connector;
+ char phy_name[10];
bool ret = false;
- intel_dp_prepare_link_train(intel_dp, crtc_state);
-
- if (!intel_dp_link_training_clock_recovery(intel_dp, crtc_state))
+ if (!intel_dp_link_training_clock_recovery(intel_dp, crtc_state, dp_phy))
goto out;
- if (!intel_dp_link_training_channel_equalization(intel_dp, crtc_state))
+ if (!intel_dp_link_training_channel_equalization(intel_dp, crtc_state, dp_phy))
goto out;
ret = true;
out:
drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
- "[CONNECTOR:%d:%s] Link Training %s at link rate = %d, lane count = %d",
+ "[CONNECTOR:%d:%s] Link Training %s at link rate = %d, lane count = %d, at %s",
intel_connector->base.base.id,
intel_connector->base.name,
ret ? "passed" : "failed",
- crtc_state->port_clock, crtc_state->lane_count);
+ crtc_state->port_clock, crtc_state->lane_count,
+ intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)));
return ret;
}
schedule_work(&intel_connector->modeset_retry_work);
}
+/* Perform the link training on all LTTPRs and the DPRX on a link. */
+static bool
+intel_dp_link_train_all_phys(struct intel_dp *intel_dp,
+ const struct intel_crtc_state *crtc_state,
+ int lttpr_count)
+{
+ bool ret = true;
+ int i;
+
+ intel_dp_prepare_link_train(intel_dp, crtc_state);
+
+ for (i = lttpr_count - 1; i >= 0; i--) {
+ enum drm_dp_phy dp_phy = DP_PHY_LTTPR(i);
+
+ ret = intel_dp_link_train_phy(intel_dp, crtc_state, dp_phy);
+ intel_dp_disable_dpcd_training_pattern(intel_dp, dp_phy);
+
+ if (!ret)
+ break;
+ }
+
+ if (ret)
+ intel_dp_link_train_phy(intel_dp, crtc_state, DP_PHY_DPRX);
+
+ if (intel_dp->set_idle_link_train)
+ intel_dp->set_idle_link_train(intel_dp, crtc_state);
+
+ return ret;
+}
+
/**
* intel_dp_start_link_train - start link training
* @intel_dp: DP struct
* TODO: Reiniting LTTPRs here won't be needed once proper connector
* HW state readout is added.
*/
- intel_dp_lttpr_init(intel_dp);
+ int lttpr_count = intel_dp_lttpr_init(intel_dp);
- if (!intel_dp_link_train(intel_dp, crtc_state))
+ if (!intel_dp_link_train_all_phys(intel_dp, crtc_state, lttpr_count))
intel_dp_schedule_fallback_link_training(intel_dp, crtc_state);
}