Public bug reported: Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993311] [drm:drm_add_edid_modes.part.22 [drm]] HDMI: DVI dual 0, max TMDS clock 300000 kHz Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993315] nouveau 0000:01:00.0: DRM: native mode from largest: 1920x1080@60 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993342] [drm:drm_mode_debug_printmodeline [drm]] Modeline 69:"3840x2160" 30 297000 3840 4016 4104 4400 2160 2168 2178 2250 0x48 0x5 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993348] [drm:drm_mode_prune_invalid [drm]] Not using 3840x2160 mode: CLOCK_HIGH Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993353] [drm:drm_mode_debug_printmodeline [drm]] Modeline 73:"2560x1440" 60 241500 2560 2608 2640 2720 1440 1443 1448 1481 0x40 0x9 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993358] [drm:drm_mode_prune_invalid [drm]] Not using 2560x1440 mode: CLOCK_HIGH Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993363] [drm:drm_mode_debug_printmodeline [drm]] Modeline 104:"3840x2160" 25 297000 3840 4896 4984 5280 2160 2168 2178 2250 0x40 0x5 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993368] [drm:drm_mode_prune_invalid [drm]] Not using 3840x2160 mode: CLOCK_HIGH Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993373] [drm:drm_mode_debug_printmodeline [drm]] Modeline 105:"3840x2160" 24 297000 3840 5116 5204 5500 2160 2168 2178 2250 0x40 0x5 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993378] [drm:drm_mode_prune_invalid [drm]] Not using 3840x2160 mode: CLOCK_HIGH Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993383] [drm:drm_mode_debug_printmodeline [drm]] Modeline 106:"3840x2160" 30 296703 3840 4016 4104 4400 2160 2168 2178 2250 0x40 0x5 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993387] [drm:drm_mode_prune_invalid [drm]] Not using 3840x2160 mode: CLOCK_HIGH Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993392] [drm:drm_mode_debug_printmodeline [drm]] Modeline 116:"3840x2160" 24 296703 3840 5116 5204 5500 2160 2168 2178 2250 0x40 0x5 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993397] [drm:drm_mode_prune_invalid [drm]] Not using 3840x2160 mode: CLOCK_HIGH
However it is perfectly valid to use higher pixel clock on some graphic cards. This patch will allow the end-user to adjust the pixel clock with the hdmimhz kernel parameter until the detection code gets good enough: https://github.com/torvalds/linux/commit/1a0c96c075bb4517d4ce4fb6750ee0a3cf38714c This page contains a lot of useful information and lead me to a sollution to my problem: https://www.elstel.org/software/hunt-for-4K-UHD-2160p.html.en I think this is worthy of consideration for backport to the Xenial kernel as not being able to use the most recent LTS version of Ubuntu Desktop with current hardware is a drag. ** Affects: linux (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1655421 Title: nouveau driver being too conservative about HDMI pixel clock, barring usage of native resolution on 4K displays over HDMI Status in linux package in Ubuntu: New Bug description: Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993311] [drm:drm_add_edid_modes.part.22 [drm]] HDMI: DVI dual 0, max TMDS clock 300000 kHz Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993315] nouveau 0000:01:00.0: DRM: native mode from largest: 1920x1080@60 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993342] [drm:drm_mode_debug_printmodeline [drm]] Modeline 69:"3840x2160" 30 297000 3840 4016 4104 4400 2160 2168 2178 2250 0x48 0x5 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993348] [drm:drm_mode_prune_invalid [drm]] Not using 3840x2160 mode: CLOCK_HIGH Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993353] [drm:drm_mode_debug_printmodeline [drm]] Modeline 73:"2560x1440" 60 241500 2560 2608 2640 2720 1440 1443 1448 1481 0x40 0x9 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993358] [drm:drm_mode_prune_invalid [drm]] Not using 2560x1440 mode: CLOCK_HIGH Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993363] [drm:drm_mode_debug_printmodeline [drm]] Modeline 104:"3840x2160" 25 297000 3840 4896 4984 5280 2160 2168 2178 2250 0x40 0x5 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993368] [drm:drm_mode_prune_invalid [drm]] Not using 3840x2160 mode: CLOCK_HIGH Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993373] [drm:drm_mode_debug_printmodeline [drm]] Modeline 105:"3840x2160" 24 297000 3840 5116 5204 5500 2160 2168 2178 2250 0x40 0x5 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993378] [drm:drm_mode_prune_invalid [drm]] Not using 3840x2160 mode: CLOCK_HIGH Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993383] [drm:drm_mode_debug_printmodeline [drm]] Modeline 106:"3840x2160" 30 296703 3840 4016 4104 4400 2160 2168 2178 2250 0x40 0x5 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993387] [drm:drm_mode_prune_invalid [drm]] Not using 3840x2160 mode: CLOCK_HIGH Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993392] [drm:drm_mode_debug_printmodeline [drm]] Modeline 116:"3840x2160" 24 296703 3840 5116 5204 5500 2160 2168 2178 2250 0x40 0x5 Jan 10 18:56:03 frode-MacBookPro kernel: [ 4.993397] [drm:drm_mode_prune_invalid [drm]] Not using 3840x2160 mode: CLOCK_HIGH However it is perfectly valid to use higher pixel clock on some graphic cards. This patch will allow the end-user to adjust the pixel clock with the hdmimhz kernel parameter until the detection code gets good enough: https://github.com/torvalds/linux/commit/1a0c96c075bb4517d4ce4fb6750ee0a3cf38714c This page contains a lot of useful information and lead me to a sollution to my problem: https://www.elstel.org/software/hunt-for-4K-UHD-2160p.html.en I think this is worthy of consideration for backport to the Xenial kernel as not being able to use the most recent LTS version of Ubuntu Desktop with current hardware is a drag. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1655421/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
