In the KMS world (kernel mode setting) the kernel maintains the list of real modes available. Previously (where Xorg drivers would communicate with the hardware directly), the kernel was less involved and the Xorg driver would invent the in-between modes mostly to support CRT monitors which don't have a specific native resolution. And also for legacy support just so that people don't complain that the list of modes has shrunken.
In the "modern" KMS world however we (and the kernel) recognise that LCDs only have one real resolution and one preferred (highest) refresh rate. So you will sometimes see the kernel being brutally honest and reporting one/few modes. This is reasonable because using anything other than the native mode will make the image on an LCD blurry. In an ideal world you would always use the native mode of the LCD panel and just scale things up in software if they're too small. But I know Unity7 still doesn't quite do that as well as we'd like it to... Another reason is slightly harder to explain; external monitors continue to report they support more modes than internal laptop LCD panels. They just tell us over the wire that they can do more. Which is not a software decision. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1606103 Title: modeset driver is missing some modes that the intel driver had Status in linux package in Ubuntu: Invalid Status in xorg-server package in Ubuntu: Confirmed Status in xorg-server package in Debian: New Bug description: My laptop's 4K screen (Dell XPS 15 9550) has these resolutions, according to the intel driver: 3840x2160 60.00 + 3200x1800 60.00 2880x1620 60.00 2560x1440 60.00* 2048x1536 60.00 1920x1440 60.00 1856x1392 60.01 1792x1344 60.01 2048x1152 60.00 1920x1200 59.95 1920x1080 60.00 59.93 1600x1200 60.00 1680x1050 59.95 59.88 1600x1024 60.17 1400x1050 59.98 1600x900 60.00 1280x1024 60.02 1440x900 59.89 1280x960 60.00 1368x768 60.00 1360x768 59.80 59.96 1152x864 60.00 1280x720 60.00 1024x768 60.00 1024x576 60.00 960x540 60.00 800x600 60.32 56.25 864x486 60.00 640x480 59.94 720x405 60.00 640x360 60.00 But with the modeset driver, it detects these resolutions: 3840x2160 60.00*+ 2048x1536 60.00 1920x1440 60.00 1856x1392 60.01 1792x1344 60.01 1920x1200 59.95 1920x1080 59.93 1600x1200 60.00 1680x1050 59.95 59.88 1600x1024 60.17 1400x1050 59.98 1280x1024 60.02 1440x900 59.89 1280x960 60.00 1360x768 59.80 59.96 1152x864 60.00 1024x768 60.04 60.00 960x720 60.00 928x696 60.05 896x672 60.01 960x600 60.00 960x540 59.99 800x600 60.00 60.32 56.25 840x525 60.01 59.88 800x512 60.17 700x525 59.98 640x512 60.02 720x450 59.89 640x480 60.00 59.94 680x384 59.80 59.96 576x432 60.06 512x384 60.00 400x300 60.32 56.34 320x240 60.05 It seems to be picking up some extra super-low resolutions (like 320x240) but not the higher 16:9 resolutions. I normally run it at 2560x1440, because the native resolution is too high with an external monitor attached at 1980x1080, but I can't do this with the modeset driver. I'm reporting this as per https://tjaalton.wordpress.com/2016/07/23 /intel-graphics-gen4-and-newer-now-defaults-to-modesetting-driver- on-x/, although note that there are several inaccuracies in that post - there's a typo in ‘cp /usr/share/doc/xserver-xoeg-video- intel/xorg.conf /etc/X11‘, the file doesn't exist in any case if you correct the typo, and I couldn't use ubuntu-bug to report this against xorg-xserver, because ubuntu-bug said the xorg-xserver package doesn't exist. ProblemType: Bug DistroRelease: Ubuntu 16.10 Package: xorg-server-source (not installed) Uname: Linux 4.6.4-040604-generic x86_64 .tmp.unity_support_test.0: ApportVersion: 2.20.2-0ubuntu1 Architecture: amd64 BootLog: CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins' CompositorRunning: compiz CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0' CompositorUnredirectFSW: true CurrentDesktop: Unity Date: Mon Jul 25 11:09:00 2016 DistUpgraded: 2016-07-25 02:38:44,004 DEBUG Running PostInstallScript: './xorg_fix_proprietary.py' DistroCodename: yakkety DistroVariant: ubuntu DkmsStatus: bbswitch, 0.8, 4.4.0-28-generic, x86_64: installed bbswitch, 0.8, 4.6.4-040604-generic, x86_64: installed nvidia-367, 367.35, 4.4.0-28-generic, x86_64: installed nvidia-367, 367.35, 4.6.4-040604-generic, x86_64: installed ExtraDebuggingInterest: Yes GraphicsCard: Intel Corporation HD Graphics 530 [8086:191b] (rev 06) (prog-if 00 [VGA controller]) Subsystem: Dell HD Graphics 530 [1028:06e4] InstallationDate: Installed on 2016-07-04 (20 days ago) InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) JournalErrors: Error: command ['journalctl', '-b', '--priority=warning', '--lines=1000'] failed with exit code 1: Hint: You are currently not seeing messages from other users and the system. Users in the 'systemd-journal' group can see all messages. Pass -q to turn off this notice. No journal files were opened due to insufficient permissions. MachineType: Dell Inc. XPS 15 9550 ProcKernelCmdLine: BOOT_IMAGE=/@/boot/vmlinuz-4.6.4-040604-generic root=UUID=8de7ebec-48db-48b6-9eb9-fafdee4eb7d6 ro rootflags=subvol=@ quiet splash nogpumanager vt.handoff=7 SourcePackage: xorg-server UpgradeStatus: Upgraded to yakkety on 2016-07-24 (0 days ago) dmi.bios.date: 04/07/2016 dmi.bios.vendor: Dell Inc. dmi.bios.version: 01.02.00 dmi.board.name: 0N7TVV dmi.board.vendor: Dell Inc. dmi.board.version: A01 dmi.chassis.type: 9 dmi.chassis.vendor: Dell Inc. dmi.modalias: dmi:bvnDellInc.:bvr01.02.00:bd04/07/2016:svnDellInc.:pnXPS159550:pvr:rvnDellInc.:rn0N7TVV:rvrA01:cvnDellInc.:ct9:cvr: dmi.product.name: XPS 15 9550 dmi.sys.vendor: Dell Inc. version.compiz: compiz 1:0.9.13.0+16.10.20160714.2-0ubuntu1 version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.69-1 version.libgl1-mesa-dri: libgl1-mesa-dri 12.0.1-3ubuntu2 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 12.0.1-3ubuntu2 version.xserver-xorg-core: xserver-xorg-core 2:1.18.4-1ubuntu3 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.2-1ubuntu1 version.xserver-xorg-video-ati: xserver-xorg-video-ati N/A version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20160706-1ubuntu1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau N/A To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1606103/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
