Running headless w/ HDMI dummy???

[skallal]

This is a follow up to another post of mine from yesterday. My Raspberry Pi respin on an RPI 4B was only working on 1024x768 resolution. I discovered if I rebooted with an HDMI monitor connected, it worked in the desired 1920x1080 resolution. In other words, I can't boot headless and get a full resolution display via RealVNC.

One thought is to get a micro HDMI dummy and set it for 1920x1080. But I wonder if there's a config solution that could default to 1920x1080 when there's no monitor boot up. I have other uses for the HDMI port on my monitor.

And my QSI:

Code: Select all

System:
  Kernel: 6.6.51+rpt-rpi-v8 arch: aarch64 bits: 64 compiler: gcc v: 12.2.0
    parameters: coherent_pool=1M 8250.nr_uarts=0 snd_bcm2835.enable_headphones=0
    snd_bcm2835.enable_headphones=1 snd_bcm2835.enable_hdmi=1 snd_bcm2835.enable_hdmi=0
    smsc95xx.macaddr=DC:A6:32:8B:05:31 vc_mem.mem_base=0x3eb00000 vc_mem.mem_size=0x3ff00000
    console=ttyS0,115200 console=tty1 root=PARTUUID=4f3d088a-02 rootfstype=ext4 fsck.repair=yes
    splash rootwait quiet plymouth.ignore-serial-consoles
  Desktop: Xfce v: 4.18.1 tk: Gtk v: 3.24.36 info: xfce4-panel wm: xfwm v: 4.18.0 vt: 7
    dm: LightDM v: 1.26.0 Distro: MX-23.4_rpi_arm64 Libretto Dec 30  2023 base: Debian GNU/Linux 12
    (bookworm)
Machine:
  Type: ARM System: Raspberry Pi 4 Model B Rev 1.2 details: N/A rev: c03112 serial: <filter>
CPU:
  Info: model: N/A variant: cortex-a72 bits: 64 type: MCP arch: ARMv8 family: 8 model-id: 0
    stepping: 3
  Topology: cpus: 1x cores: 4 smt: N/A cache: L1: 320 KiB desc: d-4x32 KiB; i-4x48 KiB
    L2: 1024 KiB desc: 1x1024 KiB
  Speed (MHz): avg: 1500 min/max: 600/1500 scaling: driver: cpufreq-dt governor: ondemand cores:
    1: 1500 2: 1500 3: 1500 4: 1500 bogomips: 432
  Features: Use -f option to see features
  Vulnerabilities:
  Type: gather_data_sampling status: Not affected
  Type: itlb_multihit status: Not affected
  Type: l1tf status: Not affected
  Type: mds status: Not affected
  Type: meltdown status: Not affected
  Type: mmio_stale_data status: Not affected
  Type: reg_file_data_sampling status: Not affected
  Type: retbleed status: Not affected
  Type: spec_rstack_overflow status: Not affected
  Type: spec_store_bypass status: Vulnerable
  Type: spectre_v1 mitigation: __user pointer sanitization
  Type: spectre_v2 status: Vulnerable
  Type: srbds status: Not affected
  Type: tsx_async_abort status: Not affected
Graphics:
  Device-1: bcm2711-hdmi0 driver: vc4_hdmi v: N/A bus-ID: N/A chip-ID: brcm:fef00700 class-ID: hdmi
  Device-2: bcm2711-hdmi1 driver: vc4_hdmi v: N/A bus-ID: N/A chip-ID: brcm:fef05700
    class-ID: hdmi
  Device-3: bcm2711-vc5 driver: vc4_drm v: N/A bus-ID: N/A chip-ID: brcm:gpu class-ID: gpu
  Display: x11 server: X.Org v: 1.21.1.7 compositor: xfwm v: 4.18.0 driver: X:
    loaded: modesetting unloaded: fbdev dri: vc4
    gpu: vc4-drm,vc4_crtc,vc4_dpi,vc4_dsi,vc4_firmware_kms,vc4_hdmi,vc4_hvs,vc4_txp,vc4_v3d,vc4_vec
    display-ID: :0.0 screens: 1
  Screen-1: 0 s-res: 1920x1080 s-dpi: 96 s-size: 508x285mm (20.00x11.22") s-diag: 582mm (22.93")
  Monitor-1: HDMI-A-1 mapped: HDMI-1 model: Asus VE278 serial: <filter> built: 2012
    res: 1920x1080 hz: 60 dpi: 82 gamma: 1.2 size: 598x336mm (23.54x13.23") diag: 686mm (27")
    ratio: 16:9 modes: max: 1920x1080 min: 720x400
  API: OpenGL v: 3.1 Mesa 23.2.1-1~bpo12+rpt3 renderer: V3D 4.2 direct-render: Yes
Audio:
  Device-1: bcm2711-hdmi0 driver: vc4_hdmi bus-ID: N/A chip-ID: brcm:fef00700 class-ID: hdmi
  Device-2: bcm2711-hdmi1 driver: vc4_hdmi bus-ID: N/A chip-ID: brcm:fef05700 class-ID: hdmi
  API: ALSA v: k6.6.51+rpt-rpi-v8 status: kernel-api tools: alsamixer,amixer
  Server-1: PipeWire v: 1.2.4 status: active with: 1: pipewire-pulse status: active
    2: wireplumber status: active 3: pipewire-alsa type: plugin 4: pw-jack type: plugin
    tools: pactl,pw-cat,pw-cli,wpctl
Network:
  Device-1: bcm2835-mmc driver: mmc_bcm2835 v: N/A port: N/A bus-ID: N/A chip-ID: brcm:fe300000
    class-ID: mmcnr
  IF: wlan0 state: down mac: <filter>
  Device-2: bcm2711-genet-v5 driver: bcmgenet v: N/A port: N/A bus-ID: N/A chip-ID: brcm:fd580000
    class-ID: ethernet
  IF: eth0 state: up speed: 1000 Mbps duplex: full mac: <filter>
Bluetooth:
  Device-1: pl011 driver: uart_pl011 bus-ID: N/A chip-ID: arm:fe201000 class-ID: serial
  Report: hciconfig ID: hci0 rfk-id: 0 state: up address: <filter> bt-v: 3.0 lmp-v: 5.0
    sub-v: 6119 hci-v: 5.0 rev: 17e
  Info: acl-mtu: 1021:8 sco-mtu: 64:1 link-policy: rswitch sniff link-mode: peripheral accept
    service-classes: rendering, capturing, object transfer, audio, telephony
  Device-2: pl011 driver: N/A bus-ID: N/A chip-ID: arm:serial0 class-ID: serial
Drives:
  Local Storage: total: 7.39 TiB used: 3.85 TiB (52.0%)
  ID-1: /dev/sda maj-min: 8:0 type: USB model: SATA SSD size: 119.24 GiB block-size:
    physical: 512 B logical: 512 B type: SSD serial: <filter> rev: 0153 scheme: MBR
  SMART Message: Unknown USB bridge. Flash drive/Unsupported enclosure?
  SMART Message: Unable to run smartctl. Root privileges required.
  ID-2: /dev/sdb maj-min: 8:16 type: USB vendor: Western Digital model: WD80EZAZ-11TDBA0
    size: 7.28 TiB block-size: physical: 4096 B logical: 512 B type: HDD rpm: 5400 serial: <filter>
    rev: 4009 scheme: GPT
Partition:
  ID-1: / raw-size: 118.74 GiB size: 116.76 GiB (98.34%) used: 13.64 GiB (11.7%) fs: ext4
    dev: /dev/sda2 maj-min: 8:2
Swap:
  Kernel: swappiness: 15 (default 60) cache-pressure: 100 (default)
  ID-1: swap-1 type: file size: 2 GiB used: 0 KiB (0.0%) priority: -2 file: /var/swap
Sensors:
  System Temperatures: cpu: 55.5 C mobo: N/A
  Fan Speeds (RPM): N/A
Repos:
  Packages: 1885 pm: dpkg pkgs: 1880 libs: 969 tools: apt,apt-get,aptitude,nala,synaptic
    pm: flatpak pkgs: 5
  No active apt repos in: /etc/apt/sources.list
  Active apt repos in: /etc/apt/sources.list.d/debian.list
    1: deb http://deb.debian.org/debian bookworm main contrib non-free non-free-firmware
    2: deb http://deb.debian.org/debian-security/ bookworm-security main contrib non-free non-free-firmware
    3: deb http://deb.debian.org/debian bookworm-updates main contrib non-free non-free-firmware
  Active apt repos in: /etc/apt/sources.list.d/mx.list
    1: deb [arch=arm64] http://mxrepo.com/mx/repo/ bookworm main non-free
  Active apt repos in: /etc/apt/sources.list.d/plexmediaserver.list
    1: deb [signed-by=/usr/share/keyrings/plex-archive-keyring.gpg] https://downloads.plex.tv/repo/deb public main
  Active apt repos in: /etc/apt/sources.list.d/raspi.list
    1: deb http://archive.raspberrypi.com/debian/ bookworm main
Info:
  Processes: 229 Uptime: 22h 32m Memory: 3.78 GiB used: 984 MiB (25.4%) gpu: 76 MiB Init: systemd
  v: 252 target: graphical (5) default: graphical tool: systemctl Compilers: gcc: 12.2.0 alt: 12
  Client: shell wrapper v: 5.2.15-release inxi: 3.3.26
Boot Mode: BIOS (legacy, CSM, MBR)

[m_pav]

Can't speak for the RPi but I have a dummy HDMI (with passthru) on a MX Machine I put into a Church. They have a HDMI push-button switch to change from their regular projection laptop to the Linux Desktop and back while the dummy loads keep the extended desktop alive when it's not selected.

So to answer your question, I see no reason for why it would not work for you, though I would opt for the same type that I used because there will come a day when the pass-thru will be useful to you.