drm: Use a nondestructive mode for output detect when polling
Destructive load-detection is very expensive and due to failings
elsewhere can trigger system wide stalls of up to 600ms. A simple
first step to correcting this is not to invoke such an expensive
and destructive load-detection operation automatically.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29536
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=16265
Reported-by: Bruno Prémont <bonbons@linux-vserver.org>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index 4b77351..0350e5d 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -400,7 +400,9 @@
return status;
}
-static enum drm_connector_status intel_crt_detect(struct drm_connector *connector)
+static enum drm_connector_status
+intel_crt_detect(struct drm_connector *connector,
+ bool nondestructive)
{
struct drm_device *dev = connector->dev;
struct drm_encoder *encoder = intel_attached_encoder(connector);
@@ -419,6 +421,9 @@
if (intel_crt_detect_ddc(encoder))
return connector_status_connected;
+ if (nondestructive)
+ return connector->status;
+
/* for pre-945g platforms use load detect */
if (encoder->crtc && encoder->crtc->enabled) {
status = intel_crt_load_detect(encoder->crtc, intel_encoder);
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 51d1429..e1a2a05 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1386,7 +1386,8 @@
* \return false if DP port is disconnected.
*/
static enum drm_connector_status
-intel_dp_detect(struct drm_connector *connector)
+intel_dp_detect(struct drm_connector *connector,
+ bool nondestructive)
{
struct drm_encoder *encoder = intel_attached_encoder(connector);
struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c
index a399f4b..f0de1ad 100644
--- a/drivers/gpu/drm/i915/intel_dvo.c
+++ b/drivers/gpu/drm/i915/intel_dvo.c
@@ -221,7 +221,9 @@
*
* Unimplemented.
*/
-static enum drm_connector_status intel_dvo_detect(struct drm_connector *connector)
+static enum drm_connector_status
+intel_dvo_detect(struct drm_connector *connector,
+ bool nondestructive)
{
struct drm_encoder *encoder = intel_attached_encoder(connector);
struct intel_dvo *intel_dvo = enc_to_intel_dvo(encoder);
diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index ccd4c97..2ea123d 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -139,7 +139,8 @@
}
static enum drm_connector_status
-intel_hdmi_detect(struct drm_connector *connector)
+intel_hdmi_detect(struct drm_connector *connector,
+ bool nondestructive)
{
struct drm_encoder *encoder = intel_attached_encoder(connector);
struct intel_hdmi *intel_hdmi = enc_to_intel_hdmi(encoder);
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 4fbb016..fb1bed8 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -445,7 +445,9 @@
* connected and closed means disconnected. We also send hotplug events as
* needed, using lid status notification from the input layer.
*/
-static enum drm_connector_status intel_lvds_detect(struct drm_connector *connector)
+static enum drm_connector_status
+intel_lvds_detect(struct drm_connector *connector,
+ bool nondestructive)
{
struct drm_device *dev = connector->dev;
enum drm_connector_status status = connector_status_connected;
@@ -540,7 +542,9 @@
* the LID nofication event.
*/
if (connector)
- connector->status = connector->funcs->detect(connector);
+ connector->status = connector->funcs->detect(connector,
+ true);
+
/* Don't force modeset on machines where it causes a GPU lockup */
if (dmi_check_system(intel_no_modeset_on_lid))
return NOTIFY_OK;
diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
index e3b7a7e..db6b6d4 100644
--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -1417,7 +1417,7 @@
if (!analog_connector)
return false;
- if (analog_connector->funcs->detect(analog_connector) ==
+ if (analog_connector->funcs->detect(analog_connector, true) ==
connector_status_disconnected)
return false;
@@ -1486,7 +1486,9 @@
return status;
}
-static enum drm_connector_status intel_sdvo_detect(struct drm_connector *connector)
+static enum drm_connector_status
+intel_sdvo_detect(struct drm_connector *connector,
+ bool nondestructive)
{
uint16_t response;
struct drm_encoder *encoder = intel_attached_encoder(connector);
diff --git a/drivers/gpu/drm/i915/intel_tv.c b/drivers/gpu/drm/i915/intel_tv.c
index c671f60..d20b550 100644
--- a/drivers/gpu/drm/i915/intel_tv.c
+++ b/drivers/gpu/drm/i915/intel_tv.c
@@ -1341,7 +1341,8 @@
* we have a pipe programmed in order to probe the TV.
*/
static enum drm_connector_status
-intel_tv_detect(struct drm_connector *connector)
+intel_tv_detect(struct drm_connector *connector,
+ bool nondestructive)
{
struct drm_display_mode mode;
struct drm_encoder *encoder = intel_attached_encoder(connector);
@@ -1353,7 +1354,7 @@
if (encoder->crtc && encoder->crtc->enabled) {
type = intel_tv_detect_type(intel_tv);
- } else {
+ } else if (nondestructive) {
struct drm_crtc *crtc;
int dpms_mode;
@@ -1364,10 +1365,9 @@
intel_release_load_detect_pipe(&intel_tv->base, connector,
dpms_mode);
} else
- type = -1;
- }
-
- intel_tv->type = type;
+ return connector_status_unknown;
+ } else
+ return connector->status;
if (type < 0)
return connector_status_disconnected;
