5 ms·

great write-up, fbdev is straightforward but the kernel is phasing it out in favor of DRM, I hope DRM will maintain a fbdev emulation at least. it's sad SDL2 di

by ausjke 9y ago

great write-up, fbdev is straightforward but the kernel is phasing it out in favor of DRM, I hope DRM will maintain a fbdev emulation at least. it's sad SDL2 did not have fddev support either as most people are fond of doing opengl/2d/3d-accleration these days.

digikata 9y ago
That takes me back, fbdev was pretty useful for embedded linux configured with no X, dedicated Qt apps... or even just for putting up the all important custom boot splash screen.
jdmoreira 9y ago
Anyone remember SVAlib? I wish it was still around. Maybe it should be ported on top of OpenGL and made cross platform. Would love to have something similar on macOS.
- pjmlp 9y ago
  Yes, having to make applications setuid. I used it for a while, if I remember correctly I even wrote a pixmap loader. Why not just use SDL, or would you like to port old games? Nowadays on macOS I would just use SpriteKit.
- digi_owl 9y ago
  To me Wayland is basically that for the GL generation...
jasonkostempski 9y ago
Does "DRM" here mean something other than the "DRM" most of us are used to?
- thehardsphere 9y ago
  Direct Rendering Manager: https://en.m.wikipedia.org/wiki/Direct_Rendering_Manager https://en.m.wikipedia.org/wiki/Direct_Rendering_Manager Very different from Digital Rights Management.
  - jasonkostempski 9y ago
    Phew, I thought Digital Rights Management was snaking it's way into every rendering operation on every machine. I'm sure advocates wouldn't mind that.
    - e12e 9y ago
      Fear not, HDCP makes an effort to usher in your dystopia: https://en.m.wikipedia.org/wiki/High-bandwidth_Digital_Content_Protection https://en.m.wikipedia.org/wiki/High-bandwidth_Digital_Conte...
Jasper_ 9y ago
As much as I would want to push people away from the fbdev API (doesn't support multimonitor, page flipping, cursor planes, etc.), it will be supported in an emulation layer for new DRM-based devices. Mostly for fbcon, but still supported. https://github.com/torvalds/linux/blob/master/drivers/gpu/drm/drm_fb_helper.c https://github.com/torvalds/linux/blob/master/drivers/gpu/dr...
- badsectoracula 9y ago
  Wouldn't removing it break the "never break the user space" promise Linux has?
  - lomnakkus 9y ago
    No. The "never break user space" thing (AFAIUI, at least) is about not changing existing behavior. Removal of features is a different thing altogether which usually only happens after long deprecation periods or when there's nobody around to support the code.
- ausjke 9y ago
  the issue is that Linus works at LF which are sponsored by big companies(intel, etc), whose focus is on non-embedded devices, framebuffer is extremely useful for low end embedded products that have no GPU and does not need one either, there are more low-end-embedded-graphic-devices than intel/PC/data-center machines
digi_owl 9y ago
DRI/DRM too me seems overly fiddly for what we had before. Things just seem to break in nasty ways if i do not manage to get the kernel and userspace stuff to line up within a certain range of minor versions, and i can't seem to find a good straight list of just what those lineups are. Effectively DRI/DRM seems to be developed for the major dev, by the major devs, and screw anyone and everyone that do not read every damn mailing list and IRC channel with religious fervor. Between that and the udev stuff i fear that Torvalds have gotten too trusting of his sub-system maintainers in recent years, thus resulting in interface churn because both the kernel and userspace parts are done by the same people with no regard for anyone but themselves.
- icebraining 9y ago
  I think Linus is aware of the problems: http://lkml.iu.edu//hypermail/linux/kernel/1404.0/01331.html http://lkml.iu.edu//hypermail/linux/kernel/1404.0/01331.html
  - digi_owl 9y ago
    Kinda, but the only time Sievers' antics come up is when they impact the kernel (and its developers) directly, not when it makes userspace more complicated to maintain (unless you happen to be on first name basis with the maintainers of said sub-systems).

by ausjke 9y ago

digikata 9y ago

That takes me back, fbdev was pretty useful for embedded linux configured with no X, dedicated Qt apps... or even just for putting up the all important custom boot splash screen.

jdmoreira 9y ago

Anyone remember SVAlib? I wish it was still around. Maybe it should be ported on top of OpenGL and made cross platform. Would love to have something similar on macOS.

pjmlp 9y ago
Yes, having to make applications setuid. I used it for a while, if I remember correctly I even wrote a pixmap loader. Why not just use SDL, or would you like to port old games? Nowadays on macOS I would just use SpriteKit.
digi_owl 9y ago
To me Wayland is basically that for the GL generation...

jasonkostempski 9y ago

Does "DRM" here mean something other than the "DRM" most of us are used to?

thehardsphere 9y ago
Direct Rendering Manager: https://en.m.wikipedia.org/wiki/Direct_Rendering_Manager https://en.m.wikipedia.org/wiki/Direct_Rendering_Manager Very different from Digital Rights Management.
- jasonkostempski 9y ago
  Phew, I thought Digital Rights Management was snaking it's way into every rendering operation on every machine. I'm sure advocates wouldn't mind that.
  - e12e 9y ago
    Fear not, HDCP makes an effort to usher in your dystopia: https://en.m.wikipedia.org/wiki/High-bandwidth_Digital_Content_Protection https://en.m.wikipedia.org/wiki/High-bandwidth_Digital_Conte...

Jasper_ 9y ago

As much as I would want to push people away from the fbdev API (doesn't support multimonitor, page flipping, cursor planes, etc.), it will be supported in an emulation layer for new DRM-based devices. Mostly for fbcon, but still supported. https://github.com/torvalds/linux/blob/master/drivers/gpu/drm/drm_fb_helper.c https://github.com/torvalds/linux/blob/master/drivers/gpu/dr...

badsectoracula 9y ago
Wouldn't removing it break the "never break the user space" promise Linux has?
- lomnakkus 9y ago
  No. The "never break user space" thing (AFAIUI, at least) is about not changing existing behavior. Removal of features is a different thing altogether which usually only happens after long deprecation periods or when there's nobody around to support the code.
ausjke 9y ago
the issue is that Linus works at LF which are sponsored by big companies(intel, etc), whose focus is on non-embedded devices, framebuffer is extremely useful for low end embedded products that have no GPU and does not need one either, there are more low-end-embedded-graphic-devices than intel/PC/data-center machines

digi_owl 9y ago

DRI/DRM too me seems overly fiddly for what we had before. Things just seem to break in nasty ways if i do not manage to get the kernel and userspace stuff to line up within a certain range of minor versions, and i can't seem to find a good straight list of just what those lineups are. Effectively DRI/DRM seems to be developed for the major dev, by the major devs, and screw anyone and everyone that do not read every damn mailing list and IRC channel with religious fervor. Between that and the udev stuff i fear that Torvalds have gotten too trusting of his sub-system maintainers in recent years, thus resulting in interface churn because both the kernel and userspace parts are done by the same people with no regard for anyone but themselves.

icebraining 9y ago
I think Linus is aware of the problems: http://lkml.iu.edu//hypermail/linux/kernel/1404.0/01331.html http://lkml.iu.edu//hypermail/linux/kernel/1404.0/01331.html
- digi_owl 9y ago
  Kinda, but the only time Sievers' antics come up is when they impact the kernel (and its developers) directly, not when it makes userspace more complicated to maintain (unless you happen to be on first name basis with the maintainers of said sub-systems).