Cc: <[email protected]> # v6.15+
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/5969
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14517
Signed-off-by: Ankit Nautiyal <[email protected]>
---
drivers/gpu/drm/i915/display/intel_dp.c | 31 +++++++++++++++++++--
drivers/gpu/drm/i915/display/intel_quirks.c | 9 ++++++
drivers/gpu/drm/i915/display/intel_quirks.h | 1 +
3 files changed, 39 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
b/drivers/gpu/drm/i915/display/intel_dp.c
index f48912f308df..362e376fca27 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -171,6 +171,15 @@ int intel_dp_link_symbol_clock(int rate)
return DIV_ROUND_CLOSEST(rate * 10, intel_dp_link_symbol_size(rate));
}
+static bool intel_dp_reject_hbr3_due_to_tps4(struct intel_dp *intel_dp)
+{
+ /* TPS4 is not mandatory for eDP with DPCD rev 1.4 */
+ if (intel_dp_is_edp(intel_dp) && intel_dp->dpcd[DP_DPCD_REV] == 0x14)
+ return false;
+
+ return !drm_dp_tps4_supported(intel_dp->dpcd);
+}
+
static int max_dprx_rate(struct intel_dp *intel_dp)
{
struct intel_display *display = to_intel_display(intel_dp);
@@ -187,13 +196,22 @@ static int max_dprx_rate(struct intel_dp *intel_dp)
* HBR3 without TPS4, and are unable to produce a stable
* output. Reject HBR3 when TPS4 is not available.
*/
- if (max_rate >= 810000 && !drm_dp_tps4_supported(intel_dp->dpcd)) {
+ if (max_rate >= 810000 && intel_dp_reject_hbr3_due_to_tps4(intel_dp)) {
drm_dbg_kms(display->drm,
"[ENCODER:%d:%s] Rejecting HBR3 due to missing TPS4
support\n",
encoder->base.base.id, encoder->base.name);
max_rate = 540000;
}
+ /*
+ * Some platforms + eDP panels may not reliably support HBR3
+ * due to signal integrity limitations, despite advertising it.
+ * Cap the link rate to HBR2 to avoid unstable configurations for the
+ * known machines.
+ */
+ if (intel_dp_is_edp(intel_dp) && intel_has_quirk(display,
QUIRK_EDP_LIMIT_RATE_HBR2))
+ max_rate = min(max_rate, 540000);
+
return max_rate;
}
@@ -4304,13 +4322,22 @@ intel_edp_set_sink_rates(struct intel_dp *intel_dp)
* HBR3 without TPS4, and are unable to produce a stable
* output. Reject HBR3 when TPS4 is not available.
*/
- if (rate >= 810000 &&
!drm_dp_tps4_supported(intel_dp->dpcd)) {
+ if (rate >= 810000 &&
intel_dp_reject_hbr3_due_to_tps4(intel_dp)) {
drm_dbg_kms(display->drm,
"[ENCODER:%d:%s] Rejecting HBR3 due to
missing TPS4 support\n",
encoder->base.base.id,
encoder->base.name);
break;
}
+ /*
+ * Some platforms cannot reliably drive HBR3 rates due
to PHY limitations,
+ * even if the sink advertises support. Reject any sink
rates above HBR2 on
+ * the known machines for stable output.
+ */
+ if (rate >= 810000 &&
+ intel_has_quirk(display, QUIRK_EDP_LIMIT_RATE_HBR2))
+ break;
+
intel_dp->sink_rates[i] = rate;
}
intel_dp->num_sink_rates = i;
diff --git a/drivers/gpu/drm/i915/display/intel_quirks.c
b/drivers/gpu/drm/i915/display/intel_quirks.c
index a32fae510ed2..d2e16b79d6be 100644
--- a/drivers/gpu/drm/i915/display/intel_quirks.c
+++ b/drivers/gpu/drm/i915/display/intel_quirks.c
@@ -80,6 +80,12 @@ static void quirk_fw_sync_len(struct intel_dp *intel_dp)
drm_info(display->drm, "Applying Fast Wake sync pulse count quirk\n");
}
+static void quirk_edp_limit_rate_hbr2(struct intel_display *display)
+{
+ intel_set_quirk(display, QUIRK_EDP_LIMIT_RATE_HBR2);
+ drm_info(display->drm, "Applying eDP Limit rate to HBR2 quirk\n");
+}
+
struct intel_quirk {
int device;
int subsystem_vendor;
@@ -231,6 +237,9 @@ static struct intel_quirk intel_quirks[] = {
{ 0x3184, 0x1019, 0xa94d, quirk_increase_ddi_disabled_time },
/* HP Notebook - 14-r206nv */
{ 0x0f31, 0x103c, 0x220f, quirk_invert_brightness },
+
+ /* Dell XPS 13 7390 2-in-1 */
+ { 0x8a12, 0x1028, 0x08b0, quirk_edp_limit_rate_hbr2 },
};
static const struct intel_dpcd_quirk intel_dpcd_quirks[] = {
diff --git a/drivers/gpu/drm/i915/display/intel_quirks.h
b/drivers/gpu/drm/i915/display/intel_quirks.h
index cafdebda7535..06da0e286c67 100644
--- a/drivers/gpu/drm/i915/display/intel_quirks.h
+++ b/drivers/gpu/drm/i915/display/intel_quirks.h
@@ -20,6 +20,7 @@ enum intel_quirk_id {
QUIRK_LVDS_SSC_DISABLE,
QUIRK_NO_PPS_BACKLIGHT_POWER_HOOK,
QUIRK_FW_SYNC_LEN,
+ QUIRK_EDP_LIMIT_RATE_HBR2,
};
void intel_init_quirks(struct intel_display *display);
