>Some speculate it might descend from PowerVR GPUs, as used in older iPhones, while others believe the GPU to be completely custom. But rumours and speculations are no fun when we can peek under the hood ourselves!<p>As per IMG CEO, Apple has never not been an IMG customer. ( Referring to period between 2015 and 2019.) Unfortunately that quote, along with that article has simply vanished. It was said during an Interview on a British newspaper / web site if I remember correctly.<p><i>"On 2 January 2020, Imagination Technologies announced a new multi-year license agreement with Apple including access to a wider range of Imagination's IP in exchange for license fees. This deal replaced the prior deal signed on 6 February 2014."</i> [1]<p>The Apple official Metal Feature set document [2], All Apple A Series SoC including the latest A14 supports PVRTC, which stands for PowerVR Texture Compression[3].<p>It could be a Custom GPU, but it still has plenty of PowerVR tech in it. Just like Apple Custom CPU, it is still an ARM.<p>Note: I am still bitter at what Apple has done to IMG / PowerVR.<p>[1] <a href="https://www.imaginationtech.com/news/press-release/imagination-and-apple-sign-new-agreement/" rel="nofollow">https://www.imaginationtech.com/news/press-release/imaginati...</a><p>[2] <a href="https://developer.apple.com/metal/Metal-Feature-Set-Tables.pdf" rel="nofollow">https://developer.apple.com/metal/Metal-Feature-Set-Tables.p...</a><p>[3] <a href="https://en.wikipedia.org/wiki/PVRTC" rel="nofollow">https://en.wikipedia.org/wiki/PVRTC</a>
> This suggests the hardware is superscalar, with more 16-bit ALUs than 32-bit ALUs<p>To me, it sounds like it might mean 32-bit ALUs can be used as two 16-bit ones; that's how I would approach it, unless I'm missing something? The vectorization can also happen at the superscalar level, if borrowing the instruction queue concept from out-of-order designs: buffer operations for a while until you've filled a vector unit's worth, align input data in the pipeline, execute. A smart compiler could rearrange opcodes to avoid dependency issues, and insert "flushes" or filling operations at the right time.
> Yet Metal optimization resources imply 16-bit arithmetic should be significantly faster, in addition to a reduction of register usage leading to higher thread count (occupancy).<p>I believe this is a difference between the A14 GPU and the M1 GPU; the former's 32 bit throughput is half its 16 bit throughput, whereas on the latter they are equal.
There is the implication upthread that the M1 GPU is similar to or derived from the IMGTEC PowerVR GPUs, anyone know if that is the case?<p>Also, I noticed that IMGTEC are going to write an open source mesa driver, I wonder how much code the two drivers will be able to share.<p><a href="https://riscv.org/blog/2020/11/picorio-the-raspberry-pi-like-small-board-computer-for-risc-v/" rel="nofollow">https://riscv.org/blog/2020/11/picorio-the-raspberry-pi-like...</a>
Exciting! I can't believe the incredible rate at which progress is being made on this front. And by a sophomore(?!) undergraduate student no less!
Why start with the shader compiler rather than simply whatever commands are necessary to get the screen turned on and a simple memory mapped framebuffer?<p>It would seem easier to get Linux booting (by just sending the same commands apples software does) before worrying about 3d acceleration and shaders...
Can someone explain why they would buy a Mac and install linux?<p>I used to dual boot windows for school and when I first switched to windows I had an old laptop's backup in bootcamp. Cross-platform software is much more ubiquitous than 5-10 years ago. For linux I always used another box or just run a VM. Nowadays my laptop can ssh or Remote Desktop into a more powerful machine. I have a custom built widows box, a custom built NAS running FreeNas (FreeBSD), 2 RPi's running Raspbian, and a not always linux box based on old hardware. There is a machine big or small to do things or play with. My VPN allows me to connect from anywhere.<p>What are you guys doing that you have to install linux instead of running a VM or remotely connecting to a linux box? If it's just for the sake of knowledge I can understand it.<p>Apple's touch pad experience in MacOS is the best in the market and it is always very different in Windows and Linux. The XPS, Lenovo and smaller vendors really make killer Linux/Windows laptops that have much more options than Macs.