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As far as I've understood this article, the relevant source is available. So what's the problem? Why should Intel spend time and resources to integrate it with

by zvrba 14y ago

As far as I've understood this article, the relevant source is available. So what's the problem? Why should Intel spend time and resources to integrate it with the mainstream, esp. if this is a short-lived processor family?

Aissen 14y ago
Don't get me wrong. Intel is free to do whatever it sees fit. And Linux users and enthousiasts are free to buy or not to buy Intel-based hardware. As long as they are well-informed, which is the purpose of this post.
- eswangren 14y ago
  Yeah, it's just too bad that Intel > AMD in terms of chip performance / $ right now.
  - wmf 14y ago
    Not in this market segment. AFAIK, Brazos > Atom in both CPU and GPU and AMD is usually cheaper.
ajross 14y ago
The kernel module is GPL, but all (heh, "all" -- it's a very big driver) it does is do things like memory allocation and mapping, power management, mode setting and command transfer. All the meaningful parts of the 3D engine (shader compiler, GPU code generator, etc...) are in userspace (in prebuilt binaries for MeeGo). The kernel doesn't do anything but take the output from those components and hand it to the hardware to execute.
- rwmj 14y ago
  How hard would it be to disassemble the userspace code and work out how the card works? (Serious question)
  - ajross 14y ago
    I've been exposed to the PVR driver stack professionally, so I really can't say anything specific other than that it's really large. I wouldn't suggest looking at the proprietary code at all (unless you're on a 32 bit Linux that matches MeeGo's libraries well enough, in which case you can just go ahead and use it). I think I remember being told about a project to reverse engineer the SGX, but doubt it's made much progress. Even Nouveau is just barely usable for 3D now, and that's for much more accessible (and desirable) hardware.
  - lucian1900 14y ago
    Disassembling is incompatible with clean room reverse engineering, so other techniques must be used. Nouveau used a tool (renouveau) that poked at the graphics card and reported its state before and after.
    - A1kmm 14y ago
      > Disassembling is incompatible with clean room reverse > engineering Not necessarily. The idea behind clean room development is that one part of the team uses whatever legal techniques they want to analyse software, and document everything they discover. The documents are checked to make sure they don't contain any copyrightable information from the original (if information is not copyrightable, the methods used to obtain that information, be it decompiling or analysis of behaviour don't matter). A different team, who hasn't seen the original software at all, work off the document that doesn't contain any copyrightable information from the original.
      - Aissen 14y ago
        This requires two different teams, while the nouveau/lima "blackbox strategy" (put something in, watch out's out, make conclusions, rinse, repeat) only requires one team to implement clean room.

by zvrba 14y ago

Aissen 14y ago

Don't get me wrong. Intel is free to do whatever it sees fit. And Linux users and enthousiasts are free to buy or not to buy Intel-based hardware. As long as they are well-informed, which is the purpose of this post.

eswangren 14y ago
Yeah, it's just too bad that Intel > AMD in terms of chip performance / $ right now.
- wmf 14y ago
  Not in this market segment. AFAIK, Brazos > Atom in both CPU and GPU and AMD is usually cheaper.

ajross 14y ago

The kernel module is GPL, but all (heh, "all" -- it's a very big driver) it does is do things like memory allocation and mapping, power management, mode setting and command transfer. All the meaningful parts of the 3D engine (shader compiler, GPU code generator, etc...) are in userspace (in prebuilt binaries for MeeGo). The kernel doesn't do anything but take the output from those components and hand it to the hardware to execute.

rwmj 14y ago
How hard would it be to disassemble the userspace code and work out how the card works? (Serious question)
- ajross 14y ago
  I've been exposed to the PVR driver stack professionally, so I really can't say anything specific other than that it's really large. I wouldn't suggest looking at the proprietary code at all (unless you're on a 32 bit Linux that matches MeeGo's libraries well enough, in which case you can just go ahead and use it). I think I remember being told about a project to reverse engineer the SGX, but doubt it's made much progress. Even Nouveau is just barely usable for 3D now, and that's for much more accessible (and desirable) hardware.
- lucian1900 14y ago
  Disassembling is incompatible with clean room reverse engineering, so other techniques must be used. Nouveau used a tool (renouveau) that poked at the graphics card and reported its state before and after.
  - A1kmm 14y ago
    > Disassembling is incompatible with clean room reverse > engineering Not necessarily. The idea behind clean room development is that one part of the team uses whatever legal techniques they want to analyse software, and document everything they discover. The documents are checked to make sure they don't contain any copyrightable information from the original (if information is not copyrightable, the methods used to obtain that information, be it decompiling or analysis of behaviour don't matter). A different team, who hasn't seen the original software at all, work off the document that doesn't contain any copyrightable information from the original.
    - Aissen 14y ago
      This requires two different teams, while the nouveau/lima "blackbox strategy" (put something in, watch out's out, make conclusions, rinse, repeat) only requires one team to implement clean room.