[adding Erico Nunes to Cc list] On 12/15/21 10:39, Thomas Zimmermann wrote: > (cc'ing Maxime) > > Hi > > Am 15.12.21 um 10:18 schrieb Lucas Stach: >> Hi Javier, >> >> Am Mittwoch, dem 15.12.2021 um 01:59 +0100 schrieb Javier Martinez Canillas: >>> According to disable Documentation/admin-guide/kernel-parameters.txt, this >>> parameter can be used to disable kernel modesetting. >>> >>> DRM drivers will not perform display-mode changes or accelerated rendering >>> and only the systewm system framebuffer will be available if it was set-up. >>> >> Etnaviv is a render-only driver, so will no perform any modesetting on >> a display device, so I'm not sure if it's sensible to cover it under >> the nomodeset parameter. I see that it is consistent with the other >> drivers that deal with a combined render/display device, where the >> render device also gets disabled with the nomodeset param, but it >> doesn't really match the description of what the parameter is supposed >> to do. >> >> I'm not opposed to take this patch for consistency reasons, but I would >> like to hear some more opinions from other DRM folks. > > Our assumption is that we want to disable all DRM drivers; except those > that operate on the firmware's original framebuffer. That's why the the > test is called drm_firmware_drivers_only(). > Yes, we tried to document the implicit "nomodeset" semantics to make that clear: https://cgit.freedesktop.org/drm/drm-misc/commit/?id=b22a15a5aca34c8f59b770f858b1c21d347175e0 > We know that nomodeset is a terrible name. We only kept it because it > was already there, widely used, and already does what we need. > > We had similar concerns with the v3d driver of vc4. Javier, maybe we > should leave-out such special cases for now and discuss them separately? > I was discussing the same with Erico (one of the lima driver developers). Agree that we could leave those for now. Will drop from the patch-set all the DRM drivers that don't have the DRIVER_MODESET .driver_features flag. > Best regards > Thomas > Best regards, -- Javier Martinez Canillas Linux Engineering Red Hat
