Best resolution for monitor is not respected at boot (native is 1366x768, effective is 1920x1080)

Start by reproducing the boot on a Raspberry Pi 4 with the monitor connected to HDMI0, then inspect the EDID, firmware best-mode output, and kernel framebuffer mode shown in the report. Done means the firmware and kernel select the monitor's preferred native resolution instead of 1920x1080.

Describe the bug

Booting linux on a Raspberry Pi 4 B 2GB with a monitor that has native resolution of 1366x768 plugged in the HDMI0 port, it does get image but image is very low quality and letters seem very small, a consequence of actual chosen resolution for boot being 1920x1080 instead.

The EDID does list the correct mode and does mention that that is the prerefed one, but it seem not to be respected.

Steps to reproduce the behaviour

Boot current image of ubuntu in a raspberry pi 4 b and watch chosen resolution at boot time (from firmware to kernel).

More details below.

Device (s)

Raspberry Pi 4 Mod. B

System

I don't think the distribution matters here because it seems to happen before that, but in any case I'm testing with the just released Ubuntu noble preinstalled image for arm64+raspi, server edition (not sure if desktop edition would make any difference).

Logs

The firmware boots:

RPi: BOOTSYS release VERSION:0b7b6f28 DATE: 2024/04/17 TIME: 13:51:36
BOOTMODE: 0x06 partition 0 build-ts BUILD_TIMESTAMP=1713358296 serial a0940f46 boardrev b03111 stc 452522
PM_RSTS: 0x00001000
(lines suppreseed)

RPi: BOOTLOADER release VERSION:0b7b6f28 DATE: 2024/04/17 TIME: 13:51:36
BOOTMODE: 0x06 partition 0 build-ts BUILD_TIMESTAMP=1713358296 serial a0940f46 boardrev b03111 stc 1777411
(lines suppreseed)
Boot mode: USB-MSD (04) order e
HDMI0 edid block 0 offset 0
00ffffffffffff0049f7000000000000
011a0103800000000ad7a5a2594a9624
145054afce0081c00101010101010101
0101010101017f2156aa51001e30468f
33003f432100001ea91a00a050001630
3020370020560000001a000000fd0032
4c1e5010000a202020202020000000fc
004141410a20202020202020200a016f
HDMI0 edid block 1 offset 128
020323744f109f140504131216111503
0702060123090f038301000066030c00
100080011d00bc52d01e20b8285540c4
8e2100001e011d80d0721c1620102c25
80c48e2100009e8c0ad08a20e02d1010
3e9600138e210000188c0ad090204031
200c405500138e210000180000000000
0000000000000000000000000000009d
HDMI0: best-mode 1 (limit 1) 1280x720 60 Hz CEA modes fe007f80000000000000000000000000 extensions 1
(lines suppreseed)
Read config.txt bytes     1235 hnd 0x80fa2
[MSD [03:00] 3.32 000000:03] vl805.bin not found
[MSD [03:00] 3.32 000000:03] pieeprom.upd not found
[MSD [03:00] 3.32 000000:03] recover4.elf not found
[MSD [03:00] 3.32 000000:03] recovery.elf not found
Read start4.elf bytes  2256224 hnd 0x734ef
Read fixup4.dat bytes     5434 hnd 0x79769
0x00b03111 0x00000000 0x00001fff
MEM GPU: 76 ARM: 947 TOTAL: 1023
Firmware: f4e2138c2adc8f3a92a3a65939e458f11d7298ba Feb 29 2024 12:24:53
Starting start4.elf @ 0xfeb00200 partition 0
+
[    0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd083]
[    0.000000] Linux version 6.8.0-1004-raspi (buildd@bos03-arm64-035) (aarch64-linux-gnu-gcc-13 (Ubuntu 13.2.0-23ubuntu4) 13.2.0, GNU ld (GNU Binutils for Ubuntu) 2.42) #4-Ubuntu SMP PREEMPT_DYNAMIC Sat Apr 20 
02:29:55 UTC 2024 (Ubuntu 6.8.0-1004.4-raspi 6.8.1)
[    0.000000] KASLR enabled
[    0.000000] random: crng init done
[    0.000000] Machine model: Raspberry Pi 4 Model B Rev 1.1
[    0.000000] Reserved memory: created CMA memory pool at 0x0000000027c00000, size 64 MiB
[    0.000000] OF: reserved mem: initialized node linux,cma, compatible id shared-dma-pool
(lines suppreseed)

As you can see, the EDID is correctly received, and it does indicate that best resolution is 1280x720, which does not seem correct but at least would not be too far from it.

As soon as the kernel starts and the four raspberries appear at the top of the screen, the resolution is already wrong at 1920x1080. It does finish booting and when I get a chance to run commands, I can see that:

ubuntu@ubuntu:~$ sudo fbset -s

mode "1920x1080"
    geometry 1920 1080 1920 1080 32
    timings 0 0 0 0 0 0 0
    rgba 8/16,8/8,8/0,8/24
endmode

This happens both with config.txt overlay for "vc4-kms-v3d", for "vc4-fkms-v3d" or without any of them.

I'll add the decoded EDID next.

Additional context

No response