drm/i915: Allow DBLSCAN user modes with eDP/LVDS/DSI

When encountering a connector with the scaling mode property both
intel and modesetting ddxs sometimes add tons of DBLSCAN modes
to the output's mode list. The idea presumably being that since the
output will be going through the panel fitter anyway we can pretend
to use any kind of mode.

Sadly that means we can't reject user modes with the DBLSCAN flag
until we know whether we're going to be using the panel's native
mode or the user mode directly. Doing otherwise means X clients using
xf86vidmode/xrandr will get a protocol error (and often self
terminate as a result) when the kernel refuses to use the requested
mode with the DBLSCAN flag.

To undo the regression we'll move the DBLSCAN checks into the
connector->mode_valid() and encoder->compute_config() hooks.

Cc: stable@vger.kernel.org
Cc: Vito Caputo <vcaputo@pengaru.com>
Reported-by: Vito Caputo <vcaputo@pengaru.com>
Fixes: e995ca0b8139 ("drm/i915: Provide a device level .mode_valid() hook")
References: https://lkml.org/lkml/2018/5/21/715
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180524125403.23445-1-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=106804
Tested-by: Arkadiusz Miskiewicz <arekm@maven.pl>
(cherry picked from commit e4dd27aadd205417a2e9ea9902b698a0252ec3a0)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index de0e22322c76ed649c2f36266e65247ed9d02c28..072b326d5ee0a77868de83818a334c68077c762e 100644 (file)
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -304,6 +304,9 @@ intel_crt_mode_valid(struct drm_connector *connector,
        int max_dotclk = dev_priv->max_dotclk_freq;
        int max_clock;
 
+       if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return MODE_NO_DBLESCAN;
+
        if (mode->clock < 25000)
                return MODE_CLOCK_LOW;
 
@@ -337,6 +340,12 @@ static bool intel_crt_compute_config(struct intel_encoder *encoder,
                                     struct intel_crtc_state *pipe_config,
                                     struct drm_connector_state *conn_state)
 {
+       struct drm_display_mode *adjusted_mode =
+               &pipe_config->base.adjusted_mode;
+
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
+
        return true;
 }
 
@@ -344,6 +353,12 @@ static bool pch_crt_compute_config(struct intel_encoder *encoder,
                                   struct intel_crtc_state *pipe_config,
                                   struct drm_connector_state *conn_state)
 {
+       struct drm_display_mode *adjusted_mode =
+               &pipe_config->base.adjusted_mode;
+
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
+
        pipe_config->has_pch_encoder = true;
 
        return true;
@@ -354,6 +369,11 @@ static bool hsw_crt_compute_config(struct intel_encoder *encoder,
                                   struct drm_connector_state *conn_state)
 {
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
+       struct drm_display_mode *adjusted_mode =
+               &pipe_config->base.adjusted_mode;
+
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
 
        pipe_config->has_pch_encoder = true;
 

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index dee3a8e659f1d6c9dbe2040abd6e2ba42020070a..2cc6faa1daa8d464d5fa2c7a063ef7d6cb3965cc 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -14469,12 +14469,22 @@ static enum drm_mode_status
 intel_mode_valid(struct drm_device *dev,
                 const struct drm_display_mode *mode)
 {
+       /*
+        * Can't reject DBLSCAN here because Xorg ddxen can add piles
+        * of DBLSCAN modes to the output's mode list when they detect
+        * the scaling mode property on the connector. And they don't
+        * ask the kernel to validate those modes in any way until
+        * modeset time at which point the client gets a protocol error.
+        * So in order to not upset those clients we silently ignore the
+        * DBLSCAN flag on such connectors. For other connectors we will
+        * reject modes with the DBLSCAN flag in encoder->compute_config().
+        * And we always reject DBLSCAN modes in connector->mode_valid()
+        * as we never want such modes on the connector's mode list.
+        */
+
        if (mode->vscan > 1)
                return MODE_NO_VSCAN;
 
-       if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
-               return MODE_NO_DBLESCAN;
-
        if (mode->flags & DRM_MODE_FLAG_HSKEW)
                return MODE_H_ILLEGAL;
 

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 8320f0e8e3bef8587b94a908bf87f3eecdf63fc5..6cce43a6eaadd48a378851e4a1c137687c874a5c 100644 (file)
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -420,6 +420,9 @@ intel_dp_mode_valid(struct drm_connector *connector,
        int max_rate, mode_rate, max_lanes, max_link_clock;
        int max_dotclk;
 
+       if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return MODE_NO_DBLESCAN;
+
        max_dotclk = intel_dp_downstream_max_dotclock(intel_dp);
 
        if (intel_dp_is_edp(intel_dp) && fixed_mode) {
@@ -1862,6 +1865,9 @@ intel_dp_compute_config(struct intel_encoder *encoder,
                                                conn_state->scaling_mode);
        }
 
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
+
        if ((IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) &&
            adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE)
                return false;

diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index 9e6956c0868835a9bcdf156c45d151ee2479b99a..5890500a3a8b6640e587070e89d805b06c99baf7 100644 (file)
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -48,6 +48,9 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
        bool reduce_m_n = drm_dp_has_quirk(&intel_dp->desc,
                                           DP_DPCD_QUIRK_LIMITED_M_N);
 
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
+
        pipe_config->has_pch_encoder = false;
        bpp = 24;
        if (intel_dp->compliance.test_data.bpc) {
@@ -366,6 +369,9 @@ intel_dp_mst_mode_valid(struct drm_connector *connector,
        if (!intel_dp)
                return MODE_ERROR;
 
+       if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return MODE_NO_DBLESCAN;
+
        max_link_clock = intel_dp_max_link_rate(intel_dp);
        max_lanes = intel_dp_max_lane_count(intel_dp);
 

diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index cf39ca90d887872ddb2de5e011041f785fda3996..f349b39201993c88f633c1154c9fc9054c90449c 100644 (file)
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -326,6 +326,9 @@ static bool intel_dsi_compute_config(struct intel_encoder *encoder,
                                                conn_state->scaling_mode);
        }
 
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
+
        /* DSI uses short packets for sync events, so clear mode flags for DSI */
        adjusted_mode->flags = 0;
 
@@ -1266,6 +1269,9 @@ intel_dsi_mode_valid(struct drm_connector *connector,
 
        DRM_DEBUG_KMS("\n");
 
+       if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return MODE_NO_DBLESCAN;
+
        if (fixed_mode) {
                if (mode->hdisplay > fixed_mode->hdisplay)
                        return MODE_PANEL;

diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c
index a70d767313aa10e198338e2e7472592827dfa347..61d908e0df0e2d75175f6f6300d0114b66f3833d 100644 (file)
--- a/drivers/gpu/drm/i915/intel_dvo.c
+++ b/drivers/gpu/drm/i915/intel_dvo.c
@@ -219,6 +219,9 @@ intel_dvo_mode_valid(struct drm_connector *connector,
        int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
        int target_clock = mode->clock;
 
+       if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return MODE_NO_DBLESCAN;
+
        /* XXX: Validate clock range */
 
        if (fixed_mode) {
@@ -254,6 +257,9 @@ static bool intel_dvo_compute_config(struct intel_encoder *encoder,
        if (fixed_mode)
                intel_fixed_panel_mode(fixed_mode, adjusted_mode);
 
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
+
        return true;
 }
 

diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index ee929f31f7db712d0f1b306571de962480758314..d8cb53ef435134b67e2f08fc5c8470f6697436d0 100644 (file)
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -1557,6 +1557,9 @@ intel_hdmi_mode_valid(struct drm_connector *connector,
        bool force_dvi =
                READ_ONCE(to_intel_digital_connector_state(connector->state)->force_audio) == HDMI_AUDIO_OFF_DVI;
 
+       if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return MODE_NO_DBLESCAN;
+
        clock = mode->clock;
 
        if ((mode->flags & DRM_MODE_FLAG_3D_MASK) == DRM_MODE_FLAG_3D_FRAME_PACKING)
@@ -1677,6 +1680,9 @@ bool intel_hdmi_compute_config(struct intel_encoder *encoder,
        int desired_bpp;
        bool force_dvi = intel_conn_state->force_audio == HDMI_AUDIO_OFF_DVI;
 
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
+
        pipe_config->has_hdmi_sink = !force_dvi && intel_hdmi->has_hdmi_sink;
 
        if (pipe_config->has_hdmi_sink)

diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index d278f24ba6ae58bf4a704dc57610a53e9b042d25..48f618dc9abbb9de03ddf594cddf67d154a872e1 100644 (file)
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -380,6 +380,8 @@ intel_lvds_mode_valid(struct drm_connector *connector,
        struct drm_display_mode *fixed_mode = intel_connector->panel.fixed_mode;
        int max_pixclk = to_i915(connector->dev)->max_dotclk_freq;
 
+       if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return MODE_NO_DBLESCAN;
        if (mode->hdisplay > fixed_mode->hdisplay)
                return MODE_PANEL;
        if (mode->vdisplay > fixed_mode->vdisplay)
@@ -429,6 +431,9 @@ static bool intel_lvds_compute_config(struct intel_encoder *intel_encoder,
        intel_fixed_panel_mode(intel_connector->panel.fixed_mode,
                               adjusted_mode);
 
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
+
        if (HAS_PCH_SPLIT(dev_priv)) {
                pipe_config->has_pch_encoder = true;
 

diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
index 25005023c243cb0526baf01f9c90d90dd3df4da2..26975df4e593b9a899c060cee398ffbdb7b5052b 100644 (file)
--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -1160,6 +1160,9 @@ static bool intel_sdvo_compute_config(struct intel_encoder *encoder,
                                                           adjusted_mode);
        }
 
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
+
        /*
         * Make the CRTC code factor in the SDVO pixel multiplier.  The
         * SDVO device will factor out the multiplier during mode_set.
@@ -1621,6 +1624,9 @@ intel_sdvo_mode_valid(struct drm_connector *connector,
        struct intel_sdvo *intel_sdvo = intel_attached_sdvo(connector);
        int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
 
+       if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return MODE_NO_DBLESCAN;
+
        if (intel_sdvo->pixel_clock_min > mode->clock)
                return MODE_CLOCK_LOW;
 

diff --git a/drivers/gpu/drm/i915/intel_tv.c b/drivers/gpu/drm/i915/intel_tv.c
index 885fc3809f7f904e8bc82e0eeee9cddd3dcef3f4..b55b5c157e384158d6c55dab6a693c2e9e5fea21 100644 (file)
--- a/drivers/gpu/drm/i915/intel_tv.c
+++ b/drivers/gpu/drm/i915/intel_tv.c
@@ -850,6 +850,9 @@ intel_tv_mode_valid(struct drm_connector *connector,
        const struct tv_mode *tv_mode = intel_tv_mode_find(connector->state);
        int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
 
+       if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return MODE_NO_DBLESCAN;
+
        if (mode->clock > max_dotclk)
                return MODE_CLOCK_HIGH;
 
@@ -877,16 +880,21 @@ intel_tv_compute_config(struct intel_encoder *encoder,
                        struct drm_connector_state *conn_state)
 {
        const struct tv_mode *tv_mode = intel_tv_mode_find(conn_state);
+       struct drm_display_mode *adjusted_mode =
+               &pipe_config->base.adjusted_mode;
 
        if (!tv_mode)
                return false;
 
-       pipe_config->base.adjusted_mode.crtc_clock = tv_mode->clock;
+       if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
+               return false;
+
+       adjusted_mode->crtc_clock = tv_mode->clock;
        DRM_DEBUG_KMS("forcing bpc to 8 for TV\n");
        pipe_config->pipe_bpp = 8*3;
 
        /* TV has it's own notion of sync and other mode flags, so clear them. */
-       pipe_config->base.adjusted_mode.flags = 0;
+       adjusted_mode->flags = 0;
 
        /*
         * FIXME: We don't check whether the input mode is actually what we want