desktop-packages team mailing list archive
-
desktop-packages team
-
Mailing list archive
-
Message #82820
[Bug 1104230] Re: DisplayPort 1.2 MST support is missing in the Intel driver
Hi Dariusz, here is my VGA output from lspci
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09) (prog-if 00 [VGA controller])
Subsystem: Dell Device 054d
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0
Interrupt: pin A routed to IRQ 48
Region 0: Memory at d1000000 (64-bit, non-prefetchable) [size=4M]
Region 2: Memory at c0000000 (64-bit, prefetchable) [size=256M]
Region 4: I/O ports at 4000 [size=64]
Expansion ROM at <unassigned> [disabled]
Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
Address: fee00018 Data: 0000
Capabilities: [d0] Power Management version 2
Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [a4] PCI Advanced Features
AFCap: TP+ FLR+
AFCtrl: FLR-
AFStatus: TP-
Kernel driver in use: i915
--
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to xserver-xorg-video-intel in Ubuntu.
https://bugs.launchpad.net/bugs/1104230
Title:
DisplayPort 1.2 MST support is missing in the Intel driver
Status in X.org xf86-video-intel:
Unknown
Status in “xserver-xorg-video-intel” package in Ubuntu:
Confirmed
Bug description:
SRU Justification:
Impact: Many users expect the possibility to use the DP1.2 MST feature which
enables them to use a number of different display setups: daisy-chaining
DP1.2 displays, some 4K displays appearing as 2 separate displays, 3D displays.
This however is not supported in Ubuntu stable kernel.
Fix: A series of 18 cherry-picks from v3.17 kernel backported to v3.16 by
the original author of the feature: David Airlie.
Regression Potential: These patches were merged upstream in v3.17 without any
reported regressions.
Original description:
I have two recent DisplayPort monitors, both supporting the 1.2
version of the standard and one containing an MST hub (DELL 2913WM).
I have an Intel Haswell based NUC connected over mini-displayport to
the display containing the hub, then the second display is plugged in
that one over DisplayPort.
DisplayPort 1.2 is enabled on the display containing the hub and the
second display lights up fine but just works as a clone of the first
display, without ever showing up in xrandr, dmesg or any other useful
logs I could find.
My understanding of MST is that the second display should show up as
DP2 on my laptop so I can configure it as I would any other display.
UPDATE: Updated the bug report after it was pointed out that the
original test hardware, a Lenovo x230 isn't DP 1.2 capable. The same
test on hardware also fails, due to missing support for MST in the
driver.
To manage notifications about this bug go to:
https://bugs.launchpad.net/xserver-xorg-video-intel/+bug/1104230/+subscriptions