There is an undocumented "video_cards_modesetting" USE flag in x11-base/xorg-drivers. That flag happened to be the solution to get a Gentoo guest running X in QEMU on my system. After a couple of days of bashing my head against a brick wall, I stumbled over https://forums.gentoo.org/viewtopic-p-7456850.html which suggested... VIDEO_CARDS="cirrus modesetting vesa" There is no documentation of "modesetting" in /usr/portage/profiles/*.desc and emerge -pv xorg-drivers | grep modesetting doesn't return any output. Besides "video_cards_modesetting" in IUSE_VIDEO_CARDS in the ebuilds, the only mention is in /usr/portage/x11-base/xorg-drivers/ChangeLog-2015 09 Jun 2012; ChÃ.-Thanh Christopher Nguyá».n <chithanh@gentoo.org> xorg-drivers-1.12.ebuild: Add modesetting flag. Reproducible: Always Steps to Reproduce: 1. grep modesetting /usr/portage/profiles/*.desc 2. emerge -pv xorg-drivers | grep modesetting Actual Results: Both of the above commands do not return any hits. Expected Results: 1. A short description of the "modesetting" flag should've shown up 2. "modesetting" should've shown up in VIDEO_CARDS=" section This is really a documention problem, but it makes problem-solving hard for end-users, when standard methods of finding available flags for a program don't work.
It is documented properly in the expected place for USE_EXPAND flags. $ grep modesetting /usr/portage/profiles/desc/video_cards.desc modesetting - VIDEO_CARDS setting to build driver for unaccelerated modesetting
My problem with this is that "emerge -pv <whatever>" will normally display all the flags for <whatever>. E.g... emerge -pv qemu ==> lists QEMU_SOFTMMU_TARGETS and QEMU_USER_TARGETS= emerge -pv ffmpeg ==> lists CPU_FLAGS_X86 and FFTOOLS= emerge -pv curl ==> lists CURL_SSL= The deceptive booby-trap for end-users is that... emerge -pv xorg-drivers ==> lists a whole bunch of VIDEO_CARDS= e.g... "intel -amdgpu -apm -ast -chips -cirrus -dummy -epson -fbdev -fglrx (-freedreno) -geode -glint -i128 -i740 -mach64 -mga -neomagic -nouveau -nv -nvidia (-omap) (-omapfb) -qxl -r128 -radeon -radeonsi -rendition -s3 -s3virge -savage -siliconmotion -sisusb (-sunbw2) (-suncg14) (-suncg3) (-suncg6) (-sunffb) (-sunleo) (-suntcx) -tdfx (-tegra) -tga -trident -tseng -vesa -via -virtualbox -vmware (-voodoo)" This looks like a comprehensive list. How is the average user supposed to know that there are additional VIDEO_CARDS= settings for xorg-drivers hidden elsewhere?
The USE flag actually seems to have been removed in the latest version 1.17. Today I wanted to install the modesetting driver but also stumbled upon that the USE flag wasn't listed. When I use eix to bring up information on xorg-drivers its output is: [I] x11-base/xorg-drivers Available versions: 1.12 1.13 1.14 1.15 1.16 1.17 {INPUT_DEVICES="acecad aiptek elographics evdev fpit hyperpen joystick keyboard libinput mouse mutouch penmount synaptics tslib vmmouse void wacom" VIDEO_CARDS="amdgpu apm ark ast chips cirrus dummy epson fbdev fglrx freedreno geode glint i128 i740 intel mach64 mga modesetting neomagic newport nouveau nv nvidia omap omapfb qxl r128 radeon radeonsi rendition s3 s3virge savage siliconmotion sis sisusb sunbw2 suncg14 suncg3 suncg6 sunffb sunleo suntcx tdfx tegra tga trident tseng v4l vesa via virtualbox vmware voodoo"} Installed versions: 1.17(10:58:31 AM 01/13/2016)(INPUT_DEVICES="evdev synaptics -acecad -aiptek -elographics -fpit -hyperpen -joystick -keyboard -libinput -mouse -mutouch -penmount -tslib -vmmouse -void -wacom" VIDEO_CARDS="intel -amdgpu -apm -ast -chips -cirrus -dummy -epson -fbdev -fglrx -freedreno -geode -glint -i128 -i740 -mach64 -mga -neomagic -nouveau -nv -nvidia -omap -omapfb -qxl -r128 -radeon -radeonsi -rendition -s3 -s3virge -savage -siliconmotion -sisusb -sunbw2 -suncg14 -suncg3 -suncg6 -sunffb -sunleo -suntcx -tdfx -tegra -tga -trident -tseng -vesa -via -virtualbox -vmware -voodoo") Homepage: https://www.gentoo.org/ Description: Meta package containing deps on all xorg drivers The modesetting is listed in VIDEO_CARDS for "Available versions" but it is not listed for the latest version (1.17). When I add VIDEO_CARDS to my USE flags and do an emerge -uvDNa @world (or x11-base/xorg-drivers specifically) there are no changes and modesetting is not pulled in. However when I try emerge -1av =x11-base/xorg-drivers-1.16 then modesetting is listed as a USE flag. Is there a bug somewhere in xorg-drivers or its ebuild, or has modesetting been removed in 1.17?
Yup, to answer my own question, modesetting has been removed as of version 1.17. See https://bugs.gentoo.org/show_bug.cgi?id=539168 modesetting is now apparently part of xorg-server itself so it looks like its not neccesary anymore to pull in xf86-video-modesetting.
