Thanks. Looks like Sutherland's "Wheel of Reincarnation <https://www2.cs.arizona.edu/~cscheid/reading/myer-sutherland-design-of-display-processors.pdf>" has not only stopped but exploded :-) Or stopped being applicable.
-- Bakul > On Aug 22, 2021, at 9:23 AM, Paul Lalonde <paul.a.lalo...@gmail.com> wrote: > > It got complicated because there's no stable interface or ISA. The hardware > evolved from fixed-function to programmable in a commercial environment where > the only meaningful measure was raw performance per dollar at many price > points. Every year the hardware spins and becomes more performant, usually > faster than Moore's law. With 3D APIs hiding the hardware details there is > no pressure to make the hardware interface uniform, pretty, or neat. And > with the need for performance there are dozens of fixed function units that > effectively need their own sub-drivers while coordinating at high performance > with the other units. > The system diagrams for GPUs look complex, but they are radical > simplifications of what's really on the inside. > > Intel really pioneered the open driver stacks, but performance generally > wasn't there. That might be changing now, but I don't know if their recently > announced discrete product line will be driver-compatible. > > Paul > > > On Sun, Aug 22, 2021 at 8:48 AM Bakul Shah <ba...@iitbombay.org > <mailto:ba...@iitbombay.org>> wrote: > The FreeBSD amdgpu.ko is over 3Mbytes of compiled code. Not counting the > "firmware" that gets loaded on the GPU board. drm/amd/amdgpu has 200K+ lines > of source code. drm/amd over 2M lines of code. Intel's i915 seems to be about > 1/10th the amd size. AIUI, this is linux GPU driver code, more or less > unchanged (FreeBSD has shim code to use it). How did the interface to an SIMD > processor get so complicated? > >> On Aug 22, 2021, at 6:44 AM, Paul Lalonde <paul.a.lalo...@gmail.com >> <mailto:paul.a.lalo...@gmail.com>> wrote: >> >> I'd love to see GPU support for Plan9. This discussion falls right into my >> professional capacity. I'll say that people generally *grossly* >> underestimate the complexity of a modern GPU and of its supporting software >> stack. The GPU driver is effectively a second operating system with shared >> memory and DMA interfaces to the host. Even bringing up a modern GPU for >> just compute tasks is a very large endeavour. >> >> That being said, if you want real hardware support, the best place to start >> is currently AMD's open-source stack. Ignoring the Vulkan bit, >> understanding their platform abstraction layer (PAL) and shader ISA >> (https://developer.amd.com/wp-content/resources/Vega_Shader_ISA_28July2017.pdf >> >> <https://developer.amd.com/wp-content/resources/Vega_Shader_ISA_28July2017.pdf>) >> is the base. The lower hardware levels are reasonably well-described in >> linux's libdrm and its AMD support in amdgpu. >> >> Opinions on how to bring this to Plan9? I don't really have any - it's a >> huge pile of work with minimal benefit. If you're looking for lightweight >> graphics, WebGL is a doable path, and almost certainly the right way to >> experiment with Plan9-like interfaces to graphics hardware. >> >> Paul >> >> >> >> On Sun, Aug 22, 2021 at 5:30 AM sirjofri <sirjofri+ml-9f...@sirjofri.de >> <mailto:sirjofri%2bml-9f...@sirjofri.de>> wrote: >> >> 22.08.2021 14:10:20 Stuart Morrow <morrow.stu...@gmail.com >> <mailto:morrow.stu...@gmail.com>>: >> > Also: >> >> people have discussed that for years >> > >> > They have? I mean I might have seen occasionally someone vaguely >> > going "some sort of GPU support would be cool to have". That isn't >> > discussion. >> >> I've even heard of someone actually making GPU stuff work on plan 9. I've >> only heard from their partner, who made a cute glenda thing on a piece of >> cloth. I chatted with her a little and told her she should encourage her >> partner for some discussion about this in our channels. It looked like >> it's some academic work, but I don't know any details about it. >> >> Worst case, someone already has a proper and good GPU implementation for >> Plan 9 and nobody knows about it. >> >> sirjofri >> >> Btw if the said person reads this: it would be nice to learn some >> details. >> >> ------------------------------------------ >> 9fans: 9fans >> Permalink: >> https://9fans.topicbox.com/groups/9fans/Tad29bfc223dc4fbe-Md3d5cd693c12f948ad4720bc >> >> <https://9fans.topicbox.com/groups/9fans/Tad29bfc223dc4fbe-Md3d5cd693c12f948ad4720bc> >> Delivery options: https://9fans.topicbox.com/groups/9fans/subscription >> <https://9fans.topicbox.com/groups/9fans/subscription> > > > > -- Bakul > > 9fans <https://9fans.topicbox.com/latest> / 9fans / see discussions > <https://9fans.topicbox.com/groups/9fans> + participants > <https://9fans.topicbox.com/groups/9fans/members> + delivery options > <https://9fans.topicbox.com/groups/9fans/subscription>Permalink > <https://9fans.topicbox.com/groups/9fans/Tad29bfc223dc4fbe-M1a557f299e542dc652b550b8> ------------------------------------------ 9fans: 9fans Permalink: https://9fans.topicbox.com/groups/9fans/Tad29bfc223dc4fbe-M69dfd52c6b6d85727b06d9dc Delivery options: https://9fans.topicbox.com/groups/9fans/subscription
