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<base href="https://bugs.freedesktop.org/" />
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Intel HD 520 failed to train DP when connected with a external monitor"
href="https://bugs.freedesktop.org/show_bug.cgi?id=93578">93578</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>Intel HD 520 failed to train DP when connected with a external monitor
</td>
</tr>
<tr>
<th>Product</th>
<td>DRI
</td>
</tr>
<tr>
<th>Version</th>
<td>DRI git
</td>
</tr>
<tr>
<th>Hardware</th>
<td>x86-64 (AMD64)
</td>
</tr>
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<th>OS</th>
<td>Linux (All)
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>major
</td>
</tr>
<tr>
<th>Priority</th>
<td>medium
</td>
</tr>
<tr>
<th>Component</th>
<td>DRM/Intel
</td>
</tr>
<tr>
<th>Assignee</th>
<td>intel-gfx-bugs@lists.freedesktop.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>mariolpantunes@gmail.com
</td>
</tr>
<tr>
<th>QA Contact</th>
<td>intel-gfx-bugs@lists.freedesktop.org
</td>
</tr>
<tr>
<th>CC</th>
<td>intel-gfx-bugs@lists.freedesktop.org
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=120796" name="attach_120796" title="dmesg log when I start the system with a external monitor connected.">attachment 120796</a> <a href="attachment.cgi?id=120796&action=edit" title="dmesg log when I start the system with a external monitor connected.">[details]</a></span>
dmesg log when I start the system with a external monitor connected.
Dear all, I have a dell XPS 13 9350, with a external bus DA200. This adapter
connects to the USB-C port and provides HDMI, VGA, 1x USB 3 and Ethernet. The
usb port and the Ethernet are working correctly. However I am unable to connect
a external monitor.
I am using Slackware64-current with the latest 4.4 kernel (rc8).
The dmesg log points to drm intel drivers as the culprit:
[ 4.526617] [<ffffffffc02d3c4a>] skl_update_other_pipe_wm+0x1ba/0x1c0
[i915]
[ 4.526628] [<ffffffffc02d3e81>] skl_update_wm+0x231/0x720 [i915]
[ 4.526642] [<ffffffffc02d82ee>] intel_update_watermarks+0x1e/0x30 [i915]
[ 4.526660] [<ffffffffc033ed28>] haswell_crtc_enable+0x378/0x860 [i915]
[ 4.526677] [<ffffffffc033a9f5>] intel_atomic_commit+0x475/0x13c0 [i915]
[ 4.526702] [<ffffffffc0351bde>] intel_fbdev_output_poll_changed+0x1e/0x30
[i915]
[ 4.671697] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU
pipe B FIFO underrun
[ 5.072287] [drm:intel_dp_link_training_channel_equalization [i915]] *ERROR*
failed to train DP, aborting
[ 5.488287] [drm:intel_dp_link_training_channel_equalization [i915]] *ERROR*
failed to train DP, aborting
[ 5.904336] [drm:intel_dp_link_training_channel_equalization [i915]] *ERROR*
failed to train DP, aborting</pre>
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