[REGRESSION] Kernel 3.5 to 3.7-rc4 / GMA500 / DPMS sometimes crashes system

[REGRESSION] Kernel 3.5 to 3.7-rc4 / GMA500 / DPMS sometimes crashes system

[Chini, Georg (HP App Services)]

Hello,

I have an issue with the GMA500 driver for kernels from 3.5 up to 3.7-rc4.
I am using an Intel board with a D2700 Atom processor running Debian unstable.
Sometimes when DPMS switches off the screen the system reboots. More often it
does not reboot but shows a white screen on reactivation. Then I can ssh into
the box from another host but the white screen remains even if I restart X or
change VT. This never seems to happen the first time the screen is switched off,
generally it takes 3 or 4 cycles to trigger the bug. Kernel 3.4.3 works fine.
There are no messages in the logs. Any idea what might cause this or how I
can debug it any further? I will supply more details on my setup if needed.
Please CC me in your reply as I am not subscribed to the list.

Thanks in advance
                 Georg Chini

Re: [REGRESSION] Kernel 3.5 to 3.7-rc4 / GMA500 / DPMS sometimes crashes system

[Alan Cox]

> generally it takes 3 or 4 cycles to trigger the bug. Kernel 3.4.3 works fine.
> There are no messages in the logs. Any idea what might cause this or how I
> can debug it any further? I will supply more details on my setup if needed.
> Please CC me in your reply as I am not subscribed to the list.

If 3.4.3 works and 3.5 fails then that is a big help as it narrows the
possible range of causes down quite a bit.

Hardware info would be helpful here but I suspect it may be a case of
doing a set of test builds to identify the offending patch.

Also anything in the log might be helpful including doing the runs with
drm.debug=255 in the kernel command line to get full traces

Alan

RE: [REGRESSION] Kernel 3.5 to 3.7-rc4 / GMA500 / DPMS sometimes crashes system

[Chini, Georg (HP App Services)]

[-- Attachment #1: Type: text/plain, Size: 2471 bytes --]

Hello Alan,

> Hardware info would be helpful here but I suspect it may be a case of
> doing a set of test builds to identify the offending patch.

Board is an Intel Mini-ITX 2700MUD, Atom 2700 processor, GMA 3650. Lspci gives:

00:00.0 Host bridge: Intel Corporation Atom Processor D2xxx/N2xxx DRAM Controller (rev 03)
00:02.0 VGA compatible controller: Intel Corporation Atom Processor D2xxx/N2xxx Integrated Graphics Controller (rev 09)
00:1b.0 Audio device: Intel Corporation N10/ICH 7 Family High Definition Audio Controller (rev 02)
00:1c.0 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 1 (rev 02)
00:1c.2 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 3 (rev 02)
00:1d.0 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #1 (rev 02)
00:1d.1 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #2 (rev 02)
00:1d.2 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #3 (rev 02)
00:1d.3 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #4 (rev 02)
00:1d.7 USB controller: Intel Corporation N10/ICH 7 Family USB2 EHCI Controller (rev 02)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev e2)
00:1f.0 ISA bridge: Intel Corporation NM10 Family LPC Controller (rev 02)
00:1f.2 SATA controller: Intel Corporation N10/ICH7 Family SATA Controller [AHCI mode] (rev 02)
00:1f.3 SMBus: Intel Corporation N10/ICH 7 Family SMBus Controller (rev 02)
01:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection
02:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection

> Also anything in the log might be helpful including doing the runs with
> drm.debug=255 in the kernel command line to get full traces

See attached file. I removed the bit where I tested switching off/on for a while, there
is no additional information. When the error occurs I find following additional lines
in the log:

Nov  9 14:53:12 pico kernel: [drm:drm_crtc_helper_set_config],
Nov  9 14:53:12 pico kernel: [drm:drm_crtc_helper_set_config], [CRTC:3] [FB:61] #connectors=1 (x y) (0 0)
Nov  9 14:53:12 pico kernel: [drm:drm_crtc_helper_set_config], [CONNECTOR:12:DVI-D-1] to [CRTC:3]
Nov  9 14:53:12 pico kernel: [drm:drm_crtc_helper_set_config],
Nov  9 14:53:12 pico kernel: [drm:drm_crtc_helper_set_config], [CRTC:4] [NOFB]

Do you need any more information?

Regards
       Georg  

[-- Attachment #2: drm.log --]
[-- Type: application/octet-stream, Size: 18889 bytes --]

Nov  9 11:13:27 pico kernel: [drm:drm_pci_init], 
Nov  9 11:13:27 pico kernel: [drm:drm_get_pci_dev], 
Nov  9 11:13:27 pico kernel: [drm:drm_get_minor], 
Nov  9 11:13:27 pico kernel: [drm:drm_get_minor], new minor assigned 64
Nov  9 11:13:27 pico kernel: [drm:drm_get_minor], 
Nov  9 11:13:27 pico kernel: [drm:drm_get_minor], new minor assigned 0
Nov  9 11:13:27 pico kernel: [drm:psb_intel_opregion_setup], OpRegion detected at 0xbf382018
Nov  9 11:13:27 pico kernel: [drm:psb_intel_opregion_setup], Public ACPI methods supported
Nov  9 11:13:27 pico kernel: [drm:psb_intel_opregion_setup], ASLE supported
Nov  9 11:13:27 pico kernel: [drm:psb_intel_init_bios], Using VBT from OpRegion: $VBT CEDARVIEW      d
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 0:"1366x768" 0 85500 1366 1436 1580 1792 768 769 773 798 0x8 0xa
Nov  9 11:13:27 pico kernel: [drm:parse_sdvo_device_mapping], No SDVO device info is found in VBT
Nov  9 11:13:27 pico kernel: [drm:parse_edp], EDP timing in vbt t1_t3 2000 t8 10 t9 2000 t10 500 t11_t12 5000
Nov  9 11:13:27 pico kernel: [drm:parse_edp], VBT reports EDP: Lane_count 1, Lane_rate 6, Bpp 18
Nov  9 11:13:27 pico kernel: [drm:parse_edp], VBT reports EDP: VSwing  0, Preemph 0
Nov  9 11:13:27 pico kernel: [drm:drm_irq_install], irq=16
Nov  9 11:13:27 pico kernel: [drm:drm_sysfs_connector_add], adding "VGA-1" to sysfs
Nov  9 11:13:27 pico kernel: [drm:drm_sysfs_hotplug_event], generating hotplug event
Nov  9 11:13:27 pico kernel: [drm:drm_edid_block_valid], Fixing EDID header, your hardware may be failing
Nov  9 11:13:27 pico kernel: [drm:drm_edid_block_valid], Fixing EDID header, your hardware may be failing
Nov  9 11:13:27 pico kernel: [drm:drm_edid_block_valid], Fixing EDID header, your hardware may be failing
Nov  9 11:13:27 pico kernel: [drm:drm_edid_block_valid], Fixing EDID header, your hardware may be failing
Nov  9 11:13:27 pico kernel: [drm:drm_sysfs_connector_add], adding "LVDS-1" to sysfs
Nov  9 11:13:27 pico kernel: [drm:drm_sysfs_hotplug_event], generating hotplug event
Nov  9 11:13:27 pico kernel: [drm:drm_sysfs_connector_add], adding "DVI-D-1" to sysfs
Nov  9 11:13:27 pico kernel: [drm:drm_sysfs_hotplug_event], generating hotplug event
Nov  9 11:13:27 pico kernel: [drm:drm_sysfs_connector_add], adding "DP-1" to sysfs
Nov  9 11:13:27 pico kernel: [drm:drm_sysfs_hotplug_event], generating hotplug event
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_dp_i2c_init], i2c_init DPDDC-B
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_dp_aux_ch], dp_aux_ch timeout status 0x51440064
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_dp_i2c_aux_ch], aux_ch failed -110
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_dp_aux_ch], dp_aux_ch timeout status 0x51440064
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_dp_i2c_aux_ch], aux_ch failed -110
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 0
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 0
Nov  9 11:13:27 pico kernel: [drm:drm_fb_helper_parse_command_line], cmdline mode for connector LVDS-1 0x0@60Hz
Nov  9 11:13:27 pico kernel: [drm:drm_helper_probe_single_connector_modes], [CONNECTOR:7:VGA-1]
Nov  9 11:13:27 pico kernel: [drm:drm_helper_probe_single_connector_modes], [CONNECTOR:7:VGA-1] disconnected
Nov  9 11:13:27 pico kernel: [drm:drm_helper_probe_single_connector_modes], [CONNECTOR:9:LVDS-1]
Nov  9 11:13:27 pico kernel: [drm:drm_helper_probe_single_connector_modes], [CONNECTOR:9:LVDS-1] disconnected
Nov  9 11:13:27 pico kernel: [drm:drm_helper_probe_single_connector_modes], [CONNECTOR:12:DVI-D-1]
Nov  9 11:13:27 pico kernel: [drm:drm_helper_probe_single_connector_modes], [CONNECTOR:12:DVI-D-1] probed modes :
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 19:"1600x1200" 60 162000 1600 1664 1856 2160 1200 1201 1204 1250 0x48 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 53:"1400x1050" 75 156000 1400 1504 1648 1896 1050 1053 1057 1099 0x40 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 52:"1400x1050" 60 101000 1400 1448 1480 1560 1050 1053 1057 1080 0x40 0x9
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 59:"1600x900" 60 118963 1600 1696 1864 2128 900 901 904 932 0x0 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 25:"1280x1024" 85 157500 1280 1344 1504 1728 1024 1025 1028 1072 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 30:"1280x1024" 75 135000 1280 1296 1440 1688 1024 1025 1028 1066 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 24:"1280x1024" 60 108000 1280 1328 1440 1688 1024 1025 1028 1066 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 56:"1440x900" 85 157000 1440 1544 1696 1952 900 903 909 948 0x40 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 55:"1440x900" 75 136750 1440 1536 1688 1936 900 903 909 942 0x40 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 54:"1440x900" 60 88750 1440 1488 1520 1600 900 903 909 926 0x40 0x9
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 50:"1280x960" 85 148500 1280 1344 1504 1728 960 961 964 1011 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 23:"1280x960" 60 108000 1280 1376 1488 1800 960 961 964 1000 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 58:"1366x768" 60 85885 1366 1439 1583 1800 768 769 772 795 0x0 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 51:"1360x768" 60 85500 1360 1424 1536 1792 768 771 777 795 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 49:"1280x800" 85 122500 1280 1360 1496 1712 800 803 809 843 0x40 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 48:"1280x800" 75 106500 1280 1360 1488 1696 800 803 809 838 0x40 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 47:"1280x800" 60 71000 1280 1328 1360 1440 800 803 809 823 0x40 0x9
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 34:"1152x864" 75 108000 1152 1216 1344 1600 864 865 868 900 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 46:"1280x768" 85 117500 1280 1360 1496 1712 768 771 778 809 0x40 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 45:"1280x768" 75 102250 1280 1360 1488 1696 768 771 778 805 0x40 0x9
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 44:"1280x768" 60 68250 1280 1328 1360 1440 768 771 778 790 0x40 0x9
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 22:"1024x768" 85 94500 1024 1072 1168 1376 768 769 772 808 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 31:"1024x768" 75 78800 1024 1040 1136 1312 768 769 772 800 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 43:"1024x768" 70 75000 1024 1048 1184 1328 768 771 777 806 0x40 0xa
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 32:"1024x768" 60 65000 1024 1048 1184 1344 768 771 777 806 0x40 0xa
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 57:"1024x576" 60 46970 1024 1064 1168 1312 576 577 580 597 0x0 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 33:"832x624" 75 57284 832 864 928 1152 624 625 628 667 0x40 0xa
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 21:"800x600" 85 56250 800 832 896 1048 600 601 604 631 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 40:"800x600" 72 50000 800 856 976 1040 600 637 643 666 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 41:"800x600" 75 49500 800 816 896 1056 600 601 604 625 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 26:"800x600" 60 40000 800 840 968 1056 600 601 605 628 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 39:"800x600" 56 36000 800 824 896 1024 600 601 603 625 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 42:"848x480" 60 33750 848 864 976 1088 480 486 494 517 0x40 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 20:"640x480" 85 36000 640 696 752 832 480 481 484 509 0x40 0xa
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 38:"640x480" 73 31500 640 664 704 832 480 489 492 520 0x40 0xa
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 27:"640x480" 75 31500 640 656 720 840 480 481 484 500 0x40 0xa
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 28:"640x480" 60 25200 640 656 752 800 480 490 492 525 0x40 0xa
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 37:"720x400" 85 35500 720 756 828 936 400 401 404 446 0x40 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 29:"720x400" 70 28320 720 738 846 900 400 412 414 449 0x40 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 36:"640x400" 85 31500 640 672 736 832 400 401 404 445 0x40 0x6
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 35:"640x350" 85 31500 640 672 736 832 350 382 385 445 0x40 0x9
Nov  9 11:13:27 pico kernel: [drm:drm_helper_probe_single_connector_modes], [CONNECTOR:14:DP-1]
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_dp_aux_ch], dp_aux_ch timeout status 0x51440064
Nov  9 11:13:27 pico kernel: [drm:drm_helper_probe_single_connector_modes], [CONNECTOR:14:DP-1] disconnected
Nov  9 11:13:27 pico kernel: [drm:drm_setup_crtcs], 
Nov  9 11:13:27 pico kernel: [drm:drm_enable_connectors], connector 7 enabled? no
Nov  9 11:13:27 pico kernel: [drm:drm_enable_connectors], connector 9 enabled? no
Nov  9 11:13:27 pico kernel: [drm:drm_enable_connectors], connector 12 enabled? yes
Nov  9 11:13:27 pico kernel: [drm:drm_enable_connectors], connector 14 enabled? no
Nov  9 11:13:27 pico kernel: [drm:drm_target_preferred], looking for cmdline mode on connector 12
Nov  9 11:13:27 pico kernel: [drm:drm_target_preferred], looking for preferred mode on connector 12
Nov  9 11:13:27 pico kernel: [drm:drm_target_preferred], found mode 1600x1200
Nov  9 11:13:27 pico kernel: [drm:drm_setup_crtcs], picking CRTCs for 2048x2048 config
Nov  9 11:13:27 pico kernel: [drm:drm_setup_crtcs], desired mode 1600x1200 set on crtc 3
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], 
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], [CRTC:3] [FB:61] #connectors=1 (x y) (0 0)
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], crtc has no fb, full mode set
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], modes are different, full mode set
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 0:"" 0 0 0 0 0 0 0 0 0 0 0x0 0x0
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 60:"1600x1200" 60 162000 1600 1664 1856 2160 1200 1201 1204 1250 0x48 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], encoder changed, full mode switch
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], crtc changed, full mode switch
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], [CONNECTOR:12:DVI-D-1] to [CRTC:3]
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], attempting to set mode from userspace
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 60:"1600x1200" 60 162000 1600 1664 1856 2160 1200 1201 1204 1250 0x48 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_mode], [CRTC:3]
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 0
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 62:"1600x1200" 60 162000 1600 1664 1856 2160 1200 1201 1204 1250 0x48 0x5
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008018: 0x0068a701 (before)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008018: 0x0068a701
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008018: 0x0068a701 (after)
Nov  9 11:13:27 pico kernel: [drm:cdv_dpll_set_clock_cdv], use their DPLL for pipe A/B
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008010: 0x7e40221c (before)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008010: 0x7e40221c
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008010: 0x7e40221c (after)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008008: 0x5200217f (before)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008008: 0x7600217f
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008008: 0x7600217f (after)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008014: 0x06080157 (before)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008014: 0x84000157
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00008014: 0x84000157 (after)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x0000801c: 0x05559000 (before)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x0000801c: 0x05552000
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x0000801c: 0x05552000 (after)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00000120: 0x003000c4 (before)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00000120: 0x003000c4
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00000120: 0x003000c4 (after)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00000220: 0x003000c4 (before)
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00000220: 0x003000c4
Nov  9 11:13:27 pico kernel: [drm:cdv_sb_write], 0x00000220: 0x003000c4 (after)
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_crtc_mode_set], Mode for pipe A:
Nov  9 11:13:27 pico kernel: [drm:drm_mode_debug_printmodeline], Modeline 60:"1600x1200" 60 162000 1600 1664 1856 2160 1200 1201 1204 1250 0x48 0x5
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_mode], [ENCODER:13:TMDS-13] set [MODE:60:1600x1200]
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 11:13:27 pico kernel: [drm:drm_calc_timestamping_constants], crtc 3: hwmode: htotal 2160, vtotal 1250, vdisplay 1200
Nov  9 11:13:27 pico kernel: [drm:drm_calc_timestamping_constants], crtc 3: clock 162000 kHz framedur 16666250 linedur 13333, pixeldur 6
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], Setting connector DPMS state to on
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], 	[CONNECTOR:12:DVI-D-1] set DPMS on
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], 
Nov  9 11:13:27 pico kernel: [drm:drm_crtc_helper_set_config], [CRTC:4] [NOFB]
Nov  9 11:13:27 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 11:13:27 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:13:27 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:13:28 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 11:13:28 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:13:28 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 11:13:28 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:13:32 pico kernel: [drm:cdv_intel_dp_aux_ch], dp_aux_ch timeout status 0x51440064
Nov  9 11:13:32 pico kernel: [drm:output_poll_execute], [CONNECTOR:14:DP-1] status updated from 2 to 2
Nov  9 11:13:35 pico kernel: [drm:drm_crtc_helper_set_config], 
Nov  9 11:13:35 pico kernel: [drm:drm_crtc_helper_set_config], [CRTC:3] [FB:61] #connectors=1 (x y) (0 0)
Nov  9 11:13:35 pico kernel: [drm:drm_crtc_helper_set_config], [CONNECTOR:12:DVI-D-1] to [CRTC:3]
Nov  9 11:13:35 pico kernel: [drm:drm_crtc_helper_set_config], 
Nov  9 11:13:35 pico kernel: [drm:drm_crtc_helper_set_config], [CRTC:4] [NOFB]
Nov  9 11:13:35 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 11:24:47 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:24:47 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:24:47 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 0
Nov  9 11:24:47 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:24:47 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 11:24:47 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:24:47 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:24:47 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 0
Nov  9 11:24:47 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:24:47 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 11:24:47 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:25:23 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 11:25:23 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 0
Nov  9 11:25:23 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!

... lots of this each time the screen is switched on/off

Nov  9 14:52:45 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 14:52:45 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 0
Nov  9 14:52:45 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 14:53:02 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 14:53:02 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 14:53:02 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 14:53:02 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 0
Nov  9 14:53:02 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 14:53:02 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 14:53:02 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 14:53:12 pico kernel: [drm:drm_crtc_helper_set_config], 
Nov  9 14:53:12 pico kernel: [drm:drm_crtc_helper_set_config], [CRTC:3] [FB:61] #connectors=1 (x y) (0 0)
Nov  9 14:53:12 pico kernel: [drm:drm_crtc_helper_set_config], [CONNECTOR:12:DVI-D-1] to [CRTC:3]
Nov  9 14:53:12 pico kernel: [drm:drm_crtc_helper_set_config], 
Nov  9 14:53:12 pico kernel: [drm:drm_crtc_helper_set_config], [CRTC:4] [NOFB]
Nov  9 14:53:12 pico kernel: [drm:cdv_intel_single_pipe_active], pipe enabled 1
Nov  9 14:55:05 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!
Nov  9 14:55:05 pico kernel: [drm:cdv_get_max_backlight], LVDS Panel PWM value is 0!