WelcomeWelcome | FAQFAQ | DownloadsDownloads | WikiWiki

Author Topic: kmod for new kernel versions  (Read 777 times)

Offline mortegai

  • Jr. Member
  • **
  • Posts: 54
kmod for new kernel versions
« on: January 20, 2023, 04:54:53 AM »
Since Oct-2022 in newer kernel versions (5.15.y and later), the vc4 module (Broadcom VC4 Graphics Driver) has a softdep of snd-soc-hdmi-codec. 
The Busybox's modutils applets (modprobe, ...) don't deal with these softdeps, which prevents the correct initialization of the vc4 module and this causes the lack of display on the screen. 

Therefore, I think that for the next versions of piCore those Busybox applets should be replaced by kmod.

Offline Juanito

  • Administrator
  • Hero Member
  • *****
  • Posts: 14485
Re: kmod for new kernel versions
« Reply #1 on: January 20, 2023, 05:33:05 AM »
Does “modinfo vc4" show the dep? If not, I don’t think busybox modprobe will load it.

You could also test with modutils modprobe?

Offline mortegai

  • Jr. Member
  • **
  • Posts: 54
Re: kmod for new kernel versions
« Reply #2 on: January 20, 2023, 09:47:16 AM »
busybox modinfo vc4
Code: [Select]
filename:       /lib/modules/5.15.84-v8+/kernel/drivers/gpu/drm/vc4/vc4.ko.xz
author:         Eric Anholt <eric@anholt.net>
description:    Broadcom VC4 DRM Driver
license:        GPL v2
parm:           fkms_max_refresh_rate:Max supported refresh rate
parm:           tv_norm:Default TV norm.
Supported: NTSC, NTSC-J, NTSC-443, PAL, PAL-M, PAL-N,
PAL60, SECAM.
Default: PAL if a 50 Hz mode has been set via video=,
NTSC otherwise
alias:          platform:vc4-drm
alias:          of:N*T*Cbrcm,cygnus-vc4C*
alias:          of:N*T*Cbrcm,cygnus-vc4
alias:          of:N*T*Cbrcm,bcm2835-vc4C*
alias:          of:N*T*Cbrcm,bcm2835-vc4
alias:          of:N*T*Cbrcm,bcm2711-vc5C*
alias:          of:N*T*Cbrcm,bcm2711-vc5
srcversion:     9B908D65E2229E5ABCCE5AD
depends:        cec,drm,drm_kms_helper,snd-soc-core
intree:         Y
vermagic:       5.15.84-v8+ SMP preempt mod_unload modversions aarch64
not show the softdeps.
------------------------------------------------
modinfo (kmod)
modinfo vc4
Code: [Select]
filename:       /lib/modules/5.15.84-v8+/kernel/drivers/gpu/drm/vc4/vc4.ko.xz
license:        GPL v2
author:         Eric Anholt <eric@anholt.net>
description:    Broadcom VC4 DRM Driver
softdep:        pre: snd-soc-hdmi-codec
alias:          platform:vc4-drm
srcversion:     9B908D65E2229E5ABCCE5AD
alias:          of:N*T*Cbrcm,cygnus-vc4C*
alias:          of:N*T*Cbrcm,cygnus-vc4
alias:          of:N*T*Cbrcm,bcm2835-vc4C*
alias:          of:N*T*Cbrcm,bcm2835-vc4
alias:          of:N*T*Cbrcm,bcm2711-vc5C*
alias:          of:N*T*Cbrcm,bcm2711-vc5
depends:        cec,drm,drm_kms_helper,snd-soc-core
intree:         Y
name:           vc4
vermagic:       5.15.84-v8+ SMP preempt mod_unload modversions aarch64
parm:           tv_norm:Default TV norm.
Supported: NTSC, NTSC-J, NTSC-443, PAL, PAL-M, PAL-N,
PAL60, SECAM.
Default: PAL if a 50 Hz mode has been set via video=,
NTSC otherwise (charp)
parm:           force_hotplug:int
parm:           fkms_max_refresh_rate:Max supported refresh rate (int)
show the softdeps.
--------------------------------------------------
modutils is quite old and doesn't handle softdeps

Offline Paul_123

  • Administrator
  • Hero Member
  • *****
  • Posts: 1058
Re: kmod for new kernel versions
« Reply #3 on: January 24, 2023, 02:40:22 PM »
softdeps are only handled by kmod,  but the use case for softdeps is so little, just load the driver yourself.