Setting the resolution for the graphical/framebuffer/drm console

[Anton Shepelev]

Hello, all.

antiX Linux failed to autodetect and set the native
resolution of my monitor, probably because of incorrect EDID
information or a physical defect in EDID communication
between display and GPU. I solved this problem for X11 by
manual specification of driver and resolution in xorg.conf,
but my virtual terminals -- or whatver is the term for the
consoles accessible by CTRL+ALT+Fn -- still work in the
wrong resolution, likely 1024x768. Can you help me configure
the right one?

To begin with, the machine in question is Newsmay AC8:

http://www.newsmaytech.com/product/showproduct.php?lang=en&id=74

It is connected to my Iyama ProLite E1902S display via VGA.
The display's native resolution is 1280x1024. Here is my
full inxi dump:

https://pastebin.com/raw/7vA4ftUX

of which the interesitng part is:

Device-1: Intel JasperLake [UHD Graphics] driver: i915 v: kernel
arch: Gen11 ports: active: DP-2 empty: DP-1,HDMI-A-1 bus-ID: 00:02.0
chip-ID: 8086:4e61 class-ID: 0300
Display: server: X.Org v: 1.20.11 driver: X: loaded: modesetting
gpu: i915 display-ID: :0.0 screens: 1
Screen-1: 0 s-res: 1280x1024 s-dpi: 96 s-size: 338x270mm (13.31x10.63")
s-diag: 433mm (17.03")
Monitor-1: DP-2 model-id: RGT 0x1252 serial: 16843009 res: 1280x1024
hz: 75 dpi: 203 size: 160x90mm (6.3x3.54") diag: 1168mm (46") modes:
max: 1024x768 min: 720x400
OpenGL: renderer: Mesa Intel UHD Graphics (JSL) v: 4.6 Mesa 20.3.5
direct render: Yes

Observe the discrepancy between a max resolution of 1024x768
and the actual resolution of 1280x1024 (the dump was
collected from an X terminal emulator). I belive the first
value is due to broken EDID.

While running in X, my display reports its mode as 1280x1024
at 75Hz, So my first impulse was to force that resulution
via the corresponding GRUB parameter:

GRUB_GFXMODE=1280x1024

which failing, I logged on to GRUB and asked it what was the
matter:

grub> vbeinfo
error: can't find command 'vbeinfo'
grub> videoinfo
Adapter 'Cirrus CLGD 5446 PCI Video Driver': No info available
Adapter 'Bochs PCI Video Driver': No info available
Adapter 'EFI GOP dirver':
* 0x000 1024 x 768 x 32 ...
0x001 640 x 480 x 32 ...
0x002 800 x 600 x 32 ...
EDID version: 1.4
Preferred mode: 1024x768

If this may explain my failure to set 1280x1024 in the
console, what can I do make the resolution available?

According to the kernel log (dmesg), the correct
framebuffer/DRM driver is loaded:

fbcon: Taking over console
fbcon: i915drmfb (fb0) is primary device

With the drm.debug=0xe kernel parameter, I see the following
messages at startup

https://pastebin.com/raw/ebnCTBU2

including these:

[ 3.141586] [drm:drm_helper_probe_single_connector_modes [drm_kms_helper]] [CONNECTOR:233:DP-2] probed modes :
[ 3.141594] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1024x768": 60 65000 1024 1048 1184 1344 768 771 777 806 0x48 0x5
[ 3.141600] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1920x1080": 60 148500 1920 2008 2052 2200 1080 1084 1089 1125 0x40 0xa
[ 3.141606] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1400x1050": 60 121750 1400 1488 1632 1864 1050 1053 1057 1089 0x40 0x6
[ 3.141612] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1600x900": 60 108000 1600 1624 1704 1800 900 901 904 1000 0x40 0x5
[ 3.141617] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1280x1024": 75 135000 1280 1296 1440 1688 1024 1025 1028 1066 0x40 0x5
[ 3.141623] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1280x1024": 60 108000 1280 1328 1440 1688 1024 1025 1028 1066 0x40 0x5
[ 3.141628] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1440x900": 60 106500 1440 1520 1672 1904 900 903 909 934 0x40 0x6
[ 3.141633] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1280x960": 60 108000 1280 1376 1488 1800 960 961 964 1000 0x40 0x5
[ 3.141639] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1366x768": 60 85500 1366 1414 1557 1792 768 769 796 798 0x40 0x5
[ 3.141644] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1280x800": 60 83500 1280 1344 1472 1680 800 801 829 831 0x40 0x5
[ 3.141650] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1152x864": 75 108000 1152 1216 1344 1600 864 865 868 900 0x40 0x5
[ 3.141655] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1280x768": 60 79500 1280 1328 1456 1664 768 769 796 798 0x40 0x5
[ 3.141660] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1280x720": 60 74250 1280 1390 1430 1650 720 725 730 750 0x40 0x5
[ 3.141666] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1024x768": 75 78750 1024 1040 1136 1312 768 769 772 800 0x40 0x5
[ 3.141671] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1024x768": 70 75000 1024 1048 1184 1328 768 771 777 806 0x40 0xa
[ 3.141676] [drm:drm_mode_debug_printmodeline [drm]] Modeline "1024x768": 60 65000 1024 1048 1184 1344 768 771 777 806 0x40 0xa
[ 3.141770] [drm:drm_mode_debug_printmodeline [drm]] Modeline "832x624": 75 57284 832 864 928 1152 624 625 628 667 0x40 0xa
[ 3.141776] [drm:drm_mode_debug_printmodeline [drm]] Modeline "800x600": 75 49500 800 816 896 1056 600 601 604 625 0x40 0x5
[ 3.141781] [drm:drm_mode_debug_printmodeline [drm]] Modeline "800x600": 72 50000 800 856 976 1040 600 637 643 666 0x40 0x5
[ 3.141875] [drm:drm_mode_debug_printmodeline [drm]] Modeline "800x600": 60 40000 800 840 968 1056 600 601 605 628 0x40 0x5
[ 3.141881] [drm:drm_mode_debug_printmodeline [drm]] Modeline "640x480": 75 31500 640 656 720 840 480 481 484 500 0x40 0xa
[ 3.141886] [drm:drm_mode_debug_printmodeline [drm]] Modeline "640x480": 73 31500 640 664 704 832 480 489 492 520 0x40 0xa
[ 3.141892] [drm:drm_mode_debug_printmodeline [drm]] Modeline "640x480": 67 30240 640 704 768 864 480 483 486 525 0x40 0xa
[ 3.141897] [drm:drm_mode_debug_printmodeline [drm]] Modeline "640x480": 60 25175 640 656 752 800 480 490 492 525 0x40 0xa
[ 3.141902] [drm:drm_mode_debug_printmodeline [drm]] Modeline "720x400": 70 28320 720 738 846 900 400 412 414 449 0x40 0x6
[ 3.141909] [drm:drm_client_modeset_probe [drm]] connector 215 enabled? no
[ 3.141915] [drm:drm_client_modeset_probe [drm]] connector 225 enabled? no
[ 3.141921] [drm:drm_client_modeset_probe [drm]] connector 233 enabled? yes
[ 3.141931] [drm:drm_client_modeset_probe [drm]] Not using firmware configuration
[ 3.141938] [drm:drm_client_modeset_probe [drm]] looking for cmdline mode on connector 233
[ 3.141943] [drm:drm_client_modeset_probe [drm]] looking for preferred mode on connector 233 0
[ 3.141948] [drm:drm_client_modeset_probe [drm]] found mode 1024x768
[ 3.141954] [drm:drm_client_modeset_probe [drm]] picking CRTCs for 16384x16384 config
[ 3.141960] [drm:drm_client_modeset_probe [drm]] desired mode 1024x768 set on crtc 91 (0,0)

An attempt to set the native resolution via `fbset' fails as
well:

$ fbset 1280x1024-75
ioctl FBIOPUT_VSCREENINFO: Invalid argument

with the following in the kernel log:

[ 1377.941980] i915 0000:00:02.0: [drm:drm_fb_helper_check_var [drm_kms_helper]] fbdev emulation doesn't support changing the pixel clock, value of pixclock is ignored
[ 1377.941986] i915 0000:00:02.0: [drm:drm_fb_helper_check_var [drm_kms_helper]] fb requested width/height/bpp can't fit in current fb request 1280x1024-32 (virtual 1280x1024) > 1024x768-32

With similar success, I have tried `fbset' with various
1280x1024 modes pre-registered in /etc/fb.modes, as well as
with ones generated by gtf(1), with 8-, 24, and 32-bit
color.

The following futher confirms that only 1024x768 is
available for my consoles:

$ cat /sys/class/graphics/fb0/modes
U:1024x768p-0

whereas

cat /sys/class/graphics/fb0/mode

prints nothing.

Setting the desired mode directly fails:

$ sudo echo U:1280x1024p-0 > /sys/class/graphics/fb0/mode
-bash: /sys/class/graphics/fb0/mode: Permission denied

Just in case, I have made certain that my consoles 1..6 are
mapped to the framebuffer device:

$ con2fbmap 1
console 1 is mapped to framebuffer 0

In desperation, I have tried setting the obsolete `vga'
kernel parameter to 775, 794, and 795, but also in vain.

This above largely exhausts the advice and information I
have found concerning the configuration of the
framebuffer/drm graphical consoles, so I find myself in
need of your help in identifying the problem.

--
() ascii ribbon campaign -- against html e-mail
/\ www.asciiribbon.org -- against proprietary attachments

[Andy Burns]

Anton Shepelev wrote:

> $ fbset 1280x1024-75
> ioctl FBIOPUT_VSCREENINFO: Invalid argument

I know you eventually want 1280x1024, but does 1024x768 or 800x600 work (i.e.
can greater than 640x480 work?)

[Anton Shepelev]

Andy Burns:

> I know you eventually want 1280x1024, but does 1024x768 or
> 800x600 work (i.e. can greater than 640x480 work?)

I think I have indicdated that the effective resolution in
my virtual consoles looks like 1024x768. Yes, `fbset' can
set both said 1024x768 and 640x480 without error, but in the
latter case nothing changes except the console becomes
limited to a smaller rectangle (640x480) in the upper-left
part of the entire display area (1024x768). 800x600 will
probably work, too, because it is listed GRUB's videoinfo
(see OP). I will test it a bit later.

One other idea I have is to query my current working X11
modeline, convert it to the `fbset' mode entry, and try
with `fbset'. Will report the issue of my adventures in
that land.

P.S.: Know you of a tool that would convert X11 modelines
to fbset mode entries for me?

[Anton Shepelev]

I wrote:

> One other idea I have is to query my current working X11
> modeline, convert it to the `fbset' mode entry, and try
> with `fbset'.

I failed to do so. My display reports its graphical mode as:

1280x1024 H: 80.0 KHz V: 75.0Hz

`xvidtune -show' expounds:

"1280x1024" 135.00 1280 1296 1440 1688 1024 1025 1028 1066 +hsync +vsync

But I fail to cause the modeline calculator:

https://arachnoid.com/modelines/

to generate exactly this line, which I wanted then to re-
generate in FB format. The calculator's modeline differs
from the original one no matter what adjustments to its
inputs I try, e.g.

# 1280x1024 @ 75.00 Hz (GTF) hsync: 80.18 kHz; pclk: 138.54 MHz
Modeline "1280x1024_75.00" 138.54 1280 1368 1504 1728 1024 1025 1028 1069 -HSync +Vsync

If I modify the refresh rate slighly to get the target pixel
clock of 135.00 Hz, other parameters remain wrong. Can you
help?

[Anton Shepelev]

Now I have tried to use my working X mode in the
framebuffer:

ant@antix1:~
$ xvidtune -show

"1280x1024" 135.00 1280 1296 1440 1688 1024 1025 1028 1066 +hsync +vsync

ant@antix1:~
$ echo modeline <code>xvidtune -show</code> | ./modeline2fb
# modes.fb - video mode descriptions for fbset
#
# See fbset(8) and fb.modes(5) for more information

mode "1280x1024"
geometry 1280 1024 1280 2444 32
timings 7407 248 16 38 1 144 3
hsync high
vsync high
endmode

The last output being an entry for /etc/fb.modes, I renamed
the entry to avoid collision with an existing one, and tried
it via `fbset', but with neither success nor luck:

$sudo fbset 1280x1024-ml2fb
ioctl FBIOPUT_VSCREENINFO: Invalid argument
$sudo dmesg | tail
fb requested width/height/bpp can't fint in the fb request
1280x1024-32 (virtual 1280x2444) > 1024x768-32

I have also tried 8-, 16-, 24-bit color, and the a virtual
resolution matching the physical one.

[Anton Shepelev]

I have finally set the correct framebuffer mode via kernel
boot option:

DP-2:edid/1280x1024.bin

where `DP-2' is my device id as seen by `xrandr' and
`edid/1280x1024.bin' is a pseudo-path with the EDID firmware
for the required resolution. There is not actual file at
that location, the path is brutally hard-coded into the
Linux kernel togeher with a corresponding blob:

https://github.com/torvalds/linux/blob/master/drivers/gpu/drm/drm_edid_load.c

[Andy Burns]

Anton Shepelev wrote:

> I have finally set the correct framebuffer mode via kernel
> boot option:
>
> DP-2:edid/1280x1024.bin

Well found ... it's been quite a few years since I had to roll my own modelines
when driving a TV direct from a GPU over SCART.