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16 hours ago by spamizbad

Programmable logic seems like a space that could be disrupted with a company that has fully open-source tooling around its hardware along with great documentation. FPGA tooling is in the dark ages compared to modern software development environments. If you found such a company I will be your customer and simp/shill/stan for life.

10 hours ago by rkangel

I agree on the 'user friendliness' of FPGA tooling, but SW Engineers (myself including) often make the mistake of thinking an FPGA toolchain is like a software toolchain and therefore everything is equivalent. These are the two main reasons that FPGA toolchains aren't as open as compilers (I'm not saying they're good ones):

* Processors have a defined interface ("instruction set") that you can implement a compiler for and have it keep working. The interaction between the FPGA tooling and the FPGA targeted it much more complicated. It's a bit like graphics card drivers and the hardware, where the line between the two is blurry and you have to consider them both together as the graphics system. This means that the 'cleverness' of the design is much more exposed to the toolchain and having that open source would give a way a lot to competitors

* Synthesising FPGAs is a LOT harder and more complicated than compiling code (and compiling code is pretty hard). There are many stages in the pipeline involving synthesising the logic and laying it out on the target for best performance. To give an example, we upgraded our toolchain for a Xilinx FPGA and power consumption improved by 20% because they'd changed the ways that they segment clock domains and gate off stuff being used. Good performance in the tooling is a major differentiating factor that you might not want to give away.

9 hours ago by regularfry

That point about toolchain complexity just reminds me of where compilers were 20 years ago. You could get significant speed bumps because one vendor had an optimisation another didn't. That's probably still true for things like the intel compiler, for all I know. I do remember at one point doing computer vision stuff before NVidia ate the world that it wasn't uncommon to come across code that expected to have access to intel-compiled maths libraries to be able to run in real-time.

The point is that the free toolchains got good enough that in general you don't need to care, and I think it's reasonable to expect the same dynamics to apply here.

8 hours ago by pm215

It's still true for compilers -- for instance gcc 10 had a greater than 10% perf improvement for AArch64 targets compared to gcc 9 as a result of various optimisation work: https://community.arm.com/developer/tools-software/tools/b/t...

3 hours ago by amelius

> The point is that the free toolchains got good enough that in general you don't need to care, and I think it's reasonable to expect the same dynamics to apply here.

No the question was: would the vendor want this?

I'm referring to this comment above:

> Programmable logic seems like a space that could be disrupted with a company that has fully open-source tooling around its hardware along with great documentation. (...)

6 hours ago by Gladdyu

The difference is that software compilation is a fairly local optimization process - allowing you to change/inline one bit of generated code without significantly affecting the performance of the rest of the generated code - address space is cheap. On the other hand, especially when the fpga approaches capacity, one change could cause a significant portion of the design to have to be rerouted as space is limited causing significant performance differences or not meeting the timing requirements anymore.

13 hours ago by snvzz

There's open source tooling for a bunch of FPGAs:

QuickLogic EOS S3 (provided by QuickLogic)

Lattice iCE40 (reversed, project icestorm)

Lattice ECP5 (reversed, project trellis)

Lattice Nexus (reversed, project oxide)

Gowin GW1N (reversed, project apicula)

Xilinx family 7 (reversed, project x-ray)

With more on the works. Hopefully an AMD Xilinx will start contributing to the open source tooling themselves, as they do with CPU and GPU tooling.

8 hours ago by jhallenworld

I'm a bit skeptical on this one. Open tools may help, but for full vendor support you are going to have to use their tools.

Also I wouldn't say that their tools are in the dark ages- most of the problems with their tools stem from modern software tool design. So for example, I find Vivado / SDK to be complex yes, but also much more pleasant to use than tool chains for simple micro-controllers. An example is the total mess that is software libraries delivered via STM32CubeMX (no part migration, libraries depend on custom BSPs vs. auto-generated code, good luck preserving your fixes if their auto-generated code has bugs).

A reason that the Xilinx tools are big and complex is that they are following modern software tool practices (that I hate): it's a large Java-based tool that aims to hide the underlying relatively simple command line programs. Xilinx tools from the mid-90s are actually closer to what the open source FPGA tools look like today.

15 hours ago by krasin

Quick Logic is an FPGA manufacturer that recently started to offer chips & boards with a fully open source toolchain: https://www.quicklogic.com/tag/open-source-fpga/

12 hours ago by asddubs

AFAIK the iCE FPGAs also have open source tooling available

7 hours ago by bri3d

Not company supported, though, just reversed and company-tolerated. The investment was made by brilliant people donating their personal time, not the company funding an initiative - big difference there.

I think a truly "open" documentation and compilers model (like what AMD have been up to with their graphics cards) would still be a game-changer in the industry.

8 hours ago by ur-whale

I feel deeply sorry for the AMD manager who's going to inherit management of the Xilinx software stack.

9 hours ago by pclmulqdq

I voted "no" on this. I didn't want to see Xilinx spend years working on getting acquired instead of working on new chips (which happened to Altera), and I thought that the acquisition price was too low given the current premium that AMD stock carries.

3 hours ago by chabons

> [...] spend years working on getting acquired instead of working on new chips (which happened to Altera) [...]

I'm interested in what you mean by this. I was working at Altera at the time the acquisition went through, on the software tools mind you, but I didn't notice a significant shift in strategy. Are you referring to before or after the acquisition was announced?

2 hours ago by pclmulqdq

The move to the Intel foundry cost Altera a lot - I don't know if it was to position themselves to be acquired or if it was for some other strategy, but it was a very expensive decision. Stratix 10 on TSMC may have landed at the same time as Ultrascale+ from Xilinx.

Generally, during and after a merger, there is a lot of instability in a company as layoffs in comparable departments get figured out and company infrastructures get merged. I assume that on the software side, you were insulated from this instability since they were going to need to keep developing Quartus (or its replacement) either way and Intel had no equivalent.

I was an Altera customer before and during the merger (including after it was announced). It looked from the outside like sales teams and chip design teams had significant amounts of instability. I personally experienced months of delays getting Arria 10s (and associated FAE support) from our sales team immediately after the acquisition. Our new sales team from Intel (figured out 8 months later) was twice the size, had to push CPUs and Intel's software in addition to FPGAs, and was also dealing with the embarrassing situation around Stratix 10 delays.

4 hours ago by vzidex

>spend years working on getting acquired instead of working on new chips (which happened to Altera)

That's interesting, can you expand on this? I'm curious what could have impacted them that much (I'm a student about to finish my undergrad in comp eng)

8 hours ago by jhallenworld

Yup, I don't see how this helps Xilinx users. At best it creates some shareholder value and creates opportunities for advancement within each company.

5 hours ago by undefined


16 hours ago by oivaksef

A new FPGA company for anyone interested (well... 2012, but in chip world that's kind of new) https://theamphour.com/535-efinix-fpgas-with-sammy-cheung/

3 hours ago by ineedasername

Could be interesting... I may be greatly misunderstanding something like Apple's M1, but I think some of its performance gains are due to offloading tasks from the CPU to dedicated ASICs. That's great when you know what those tasks are going to be, and there's no reason to abandon that for known tasks. But if AMD can put as certain amount of FPGA capacity on chips then it might gain the flexibility to dynamically increase performance by offloading from the CPU to purpose-configured FPGA units in the field already, and gain performance that might be better than running it alongside everything else on the CPU, even it it's not quite at the ASIC level.

I fully recognize that I may be speculating out my *s here, and would welcome further constructive comment even if it's just to say "Um, yeah, that's not how it works".

10 minutes ago by rcxdude

The biggest problem with this concept is that while ASICs can be extremely efficient, FPGAs are much less efficient than the equivilent ASIC. The flexibility comes at a substantial power, chip area, and speed cost. So much so that e.g. raw number crunching is more efficiently done by CPUs or GPUs in almost all cases. You need a particularly quirky computation before an FPGA is a good accelerator. FPGAs are more naturally suited to applications where ultra-low (or ultra-predictable) latency, extremely high bandwidth I/O (with relatively little processing), or particularly specialised DSP is required. Most of these are best served with an FPGA with a CPU attached, as opposed to the other way around, and the cost of the FPGA is not likely to be worth the cost to the majority of users. For an example of a specialised use-case: ASIC designers use racks of them to simulate the digital logic in large-scale designs, which are otherwise far too difficult to simulate on a CPU because CPUs really struggle to simulate billions of seperate logic elements individually, and latency is a real killer for parallel processing. Even so, they run much, much slower than realtime.

14 hours ago by timlatim

I wonder if we'll ever see FPGAs in consumer CPUs, given AMD's expertise with chiplets and interconnects. Say, for programmable specialized instructions. The relatively recently published patent "Method and apparatus for efficient programmable instructions in computer systems" (https://www.freepatentsonline.com/y2020/0409707.html) seems to point that way.

10 hours ago by Traster

This is an idea that's been around forever and from a hardware perspective it's super easy. The problem is finding applications for this. You need to find something that is so difficult that it requires atleast dozens of instructions (because the FPGA isn't going to be running at the CPU clock speed so it needs to be a decent chunk of work to jsutify), is done often enough to dedicate silicon for (the FPGA can't be dark 99.999% of the time), but not often enough that you can't justify full custom implementation. Then you need to write a set of custom instructions that map to this logic, and build support for using these custom instructions into the compiler - accounting for the fact you don't just need to dispatch data to the fpga, you need to program it each time you change instruction and that takes forever in CPU terms.

It's not impossible, it's just very difficult, impacts every single part of the stack, and is very difficult to justify.

6 hours ago by DougMerritt

Correct but at the same time that overstates things, because extremely often the choice between full custom ICs versus FPGA is dictated by the expected volume of product, not just functionality considerations.

It is typically simply cheaper to deploy FPGAs in released products when the volume is small, while it may be cheaper to use full custom when the volume is in the millions to hundreds of millions, in the cases where either solution is functionally workable.

That includes amortizing the non-recurring engineering costs over the total units, which is typically higher for full custom than FPGA -- although sometimes they are actually in the same ballpark.

Aside from that you are correct; people sometimes imagine that most any application can be significantly accelerated with FPGAs, but even in the cases where fine-grained parallelism is present to be accelerated (well-known not to be the case for all application areas), the FPGA solution space is decreased by the solution space where full custom makes engineering and financial sense.

9 hours ago by regularfry

Maybe they're targeting a different arch layer? Is there any mileage in pushing that sort of tech into on-chip routing? As you get more and more cores, obviously interconnect area becomes more of a problem (and bus bandwidth more constrained). Is there much to be gained from a compiler being able to say "This next bit of code wants as much uncontended bandwidth as you can muster between 5 cores and L1"? That way, actually reconfiguring anything would be a bunch of microcode, rather than something the compiler took direct control over.

6 hours ago by einpoklum

There's some (perhaps lots) of potential for this for in-memory analytic processing (e.g. in an analytics-focused DBMS).

Also, a specific potential use of FPGAs is for pattern matching on large amounts of text/data: If you do it at all, you're likely to do it often; and it can't be a custom implementation since the circuit depends on the specific pattern.

7 hours ago by pclmulqdq

Intel at one point tried an FPGA-in-package with a server CPU. It turns out that you can't downclock/power gate parts of FPGA designs nearly as easily as you can CPU components, so the whole package had thermal regulation issues. You had to run the CPU at a very conservative frequency in order to let the FPGA use power as it needs to.

There are FPGA-SoCs out there that are mostly FPGA, and that seems like the way to go if you want to combine FPGAs and CPUs, otherwise they should probably be on separate power and heat budgets.

3 hours ago by uticus

To add to the other responses, I believe the end goal of "programmable specialized instructions" is being successfully explorer by other options than FPGA, ie the Raspberry Pi Pico state machines, for one example. Then there are also the hybrid CPU-FPGA models (or FPGA SoC) mentioned in the other replies, like the Zynq.

14 hours ago by thereisnospork

Wondering the same; from my 10,000 ft view a cpu-fpga marriage seems like the kind of thing that could transform how performant general purpose computing is done.

13 hours ago by franga2000

The same was said back when AMD started making APUs (CPUs with on-board GPUs) and I was similarly hopeful, but we saw how that went. Most attempts at heterogeneous computing have gone only as far as sticking two previously separate chips in one package - no significant integration or co-operation. Since FPGAs are even more different from CPUs than GPUs are, even more programming effort will be needed to take advantage of them, so unless AMD make some kind of revolutionary framework for programming them, I fear FPGA acceleration will get even lower use than GPUs do (excluding 3D work, of course).

10 hours ago by wu_187

APUs have come a long way since the initial ones. AMDs own are now actually decent in 1080p gaming. I built my wife a gaming pc and didn't buy a dedicated gpu, just an AMD APU and can play CS GO maxed out at decent fps.

8 hours ago by ThrowawayR2

Seems doubtful. I thought that way too in the '90s but what happened was that anything that was a common enough use case got moved into dedicated hardware (GPU, cryptographic acceleration instructions in the CPU) and anything uncommon is too hard for the average developer to write the Verilog/VHDL to implement.

12 hours ago by Aromasin

Intel picked up Altera in 2015, and now AMD picks up Xilinx in 2021. I'm curious to see whether AMD plans to do anything significant with this aquisition, or is it just executives following a path well worn?

7 hours ago by pclmulqdq

My guess was the latter, given how high AMD's market cap is currently. However, Xilinx/AMD have some common technology requirements around 2.5d integration and 7 nm IP.

I was hoping for an FPGA-SoC with some Xeon cores when Intel bought Altera, and now I'm hoping for one with Epyc cores.

13 hours ago by varispeed

I just hope they won't drop any of their CPLD chips. It would be a shame if only way to set up a simple logic circuits without having to use 74xxx was to use FPGA.

11 hours ago by LIV2

Yep, 5V tolerant CPLDs are a wonderful thing when you're making hardware for retro computers it would absolutely suck if the 9500XLs get discontinued.

4 hours ago by colejohnson66

CPLDs also have the advantage of being non volatile. That can make your circuit simpler as you just add a socket and use an external programmer. FPGAs require external storage and more.

8 hours ago by ur-whale

Indeed, they're really neat little devices and they're also dirt cheap.

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