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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Screen goes blank after boot, kernel 4.7 vs 4.6"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=97060">97060</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Screen goes blank after boot, kernel 4.7 vs 4.6
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>DRI
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>XOrg git
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>x86-64 (AMD64)
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux (All)
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </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>alexey.shumitsky@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=125278" name="attach_125278" title="dmesg kernel 4.7-rc7">attachment 125278</a> <a href="attachment.cgi?id=125278&action=edit" title="dmesg kernel 4.7-rc7">[details]</a></span>
dmesg kernel 4.7-rc7

With kernel 4.7-rc7 (drm-intel-nightly) laptop screen (LVDS) goes blank after
inteldrmfb is loaded.


4.7.0-rc7+ #1 SMP Sat Jul 23 16:05:00 CEST 2016 x86_64 x86_64 x86_64 GNU/Linux

It appears to me the problem is with setting panel to wrong mode:

[    2.737896] [drm:parse_lfp_panel_data] Found panel mode in BIOS VBT tables:
[    2.737900] [drm:drm_mode_debug_printmodeline] Modeline 0:"1366x768" 0 76110
1366 1397 1462 1560 768 772 784 814 0x8 0xa
[    2.737902] [drm:parse_lfp_panel_data] VBT initial LVDS value 300


While with previous kernel, 4.6, there was:

[    4.684175] [drm:parse_lfp_panel_data] Found panel mode in BIOS VBT tables:
[    4.684177] [drm:drm_mode_debug_printmodeline] Modeline 0:"1920x1080" 0
144200 1920 1968 2040 2116 1080 1083 1088 1137 0x8 0xa
[    4.684178] [drm:parse_lfp_panel_data] VBT initial LVDS value 33c

My notebook uses fullhd panel, so resolution should be 1920x1080 clearly.

Full dmesg obtained with drm.debug=0xe is attached.</pre>
        </div>
      </p>


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