Xilinx 7-Series vs. Efinix Titanium/Topaz for PCIe endpoint - Page 1
Forum section: electronics / general

author: jars121
author_rank: Regular Contributor
timestamp: August 12, 2024, 01:04:29 am
content: Hi all,I'm in the planning stages of a design, and I'm evaluating the various FPGA options to suit my use case. I'll have a front-end FPGA for DSP, ADC parallel interfacing, etc., with a back-end SoC for data management, networking, etc. I'd initially planned on using a Zynq MPSoC but I need a more performant GPU than that provided by the (antiquated) Mali-400 MP2.The SoC provides a PCIe Gen3x4 interface, which I'd like to use to connect the FPGA and SoC. My preference would be to accommodate Gen3 speeds, but I would consider Gen2 speeds if Gen3 is not an option. With that said, the Artix 7 FPGA line provides Gen2x4 in reasonably sized packages with sufficient resources (something in the A50T to A100T range depending on the PCIe IP utilisation I'd guess). I'm relatively comfortable with Vivado and the 'Xilinx process', and can make sense of the available Xilinx documentation and IP cores pertaining to PCIe.However, in my research I've found a particular level of enthusiasm around the Titanium series, which offers Gen4x4 in certain packages. The newly announced Topaz series seems to be a trimmed down Titanium, which offers Gen3x4 exactly as required in my design. However, I've never used Efinix before, and I have no idea as to the IP available/provided for a PCIe use case.For those that are experienced in either or both, which platform would you select in 2024 for a Gen3x4 endpoint use case, that offers performance, reasonable packaging/cost and a toolset that won't have me tearing my hair out?Edit: I probably shouldn't discount the newer Artix and Spartan Ultrascale+ options as well; they both offer either Gen3x4+ or Gen4x4+ depending on package.Thanks!

author: asmi
author_rank: Super Contributor
timestamp: August 12, 2024, 03:48:25 pm
content: A lot depends on the volume and longevity. If it's a one-off or a short-run project, then NRE is going to be a significant portion of the total cost, and so sticking with familiar process will reduce risks and development time, thus lowering the final project cost. Also the cost of actual devices is less relevant in this scenario because, again, R&D cost is going to heavily dominate the budget.

author: glenenglish
author_rank: Frequent Contributor
timestamp: August 12, 2024, 09:11:27 pm
content: I echo ASMI's quetsions about usage.If you need > 200 to 300 DMIPS, that puts you into a hard-core.although fully smoking Microblaze on an ULtrascale AU7P will run at 400 MHz.... IE 400 DMIPS. butBut more than that, consider Ultrascale MPSoC. and ZU1EG or ZU2EG ++ if you need the graphics and video outputalthough in the lower cost versions the 4 x GTR tranceivers only go at 6.6 Gbps. choose 625 /785 package.All tranceivers are independent, and can be all or a mix of Gig ethernet (SFP), USB3, SATA or PCIe.Efinix is a worthy look The Ti375 (in a 1156) with 4 banks of 4 PCIe (4 quads) with the quad core 1gig RISCV with custom instruction options isi excellent, although it doesnt have L2 cache. so relies on a good fast LPDDR4(x) memory interface.That's shipping now, and smaller package versions (676) (with only 1 or 2 quads) are coming Q1 2025.The tools are good, the company (it is a USA company ) is good. The smaller versions with hard core are sampling (Ti85, Ti136, 165). Topaz is lower yield Titanium . otherwise same device.I use both XIlinx and EfinixIf you have a bit of time (Q1/2025 full production ) the new Agilex 5 from Altera (10nm) is worth a look, has a HPS (2 x A76 and tranceivers), but is not as integrated as the MPSoC. The MPSoC really is the best choice, and very good value for money.Glen (Xilinx Alliance Partner)

author: jars121
author_rank: Regular Contributor
timestamp: August 12, 2024, 10:37:54 pm
content: Thank you both for your insights, it is greatly appreciated as always.asmi, this would be an entirely new product line, for which I'm targeting 10+ years longevity/availability, which is why I'm tending towards the newer platforms (Titanium/Topaz and the Spartan/Artix US+ options). I have 'academic' knowledge/familiarity of Xilinx, but little by why of practical design and implementation, so adopting a novel platform (like the Titanium/Topaz) isn't that much of a departure at this point in the journey.glenenglish, I'm not really looking for a soft/hard CPU implementation at this stage. I have a very capable backend SoC which a multitude of heterogenous CPU cores, coprocessors, etc. for the tasks requiring that sort of processing, where the FPGA will be providing all the parallel interfacing/processing with high-speed ADCs, pulse trains, etc. An MPSoC would be the perfect single-chip solution for this architecture, but I really need a higher performing GPU than that offered by the MPSoC (i.e. OpenGL ES 3+ support). It's a shame that the MPSoC is beholden to ARM's ~15 year old GPU...As for timeframe, I'm looking at initial prototypes in 12-18 months' time, so Q1 2025 production timelines align nicely. I'm going to continue to review the Efinix documents, and might reach out to Efinix regarding the Topaz, as I've been quite impressed with what little I've seen of them so far.

author: asmi
author_rank: Super Contributor
timestamp: August 13, 2024, 01:37:45 am
content: If you need more GPU power than I don't see how pure FPGA solutions will help matters, the only thing I can think of is implementing a PCIE slot via MPSoC and inserting external GPU into it, but I have no idea if it's even possible to get external GPU to work on ARM platform. But then again, no GPU of existence can guarantee you a 10+ years availability because they are typically only in production until the next generation comes out. So your best shot is to look for a "hard" SoC with GPU that has sufficient power. You can take a look at Nvidia's embedded devices as some of them pack some impressive GPU and CPU power, and they should be easier vis-a-vis long-term availability because they are designed for industrial applications. Then if you still need FPGA, you can connect it to that SoC via PCIE link which some of them have.

author: jars121
author_rank: Regular Contributor
timestamp: August 13, 2024, 01:57:35 am
content: I don't think I've conveyed my arrangement sufficiently, as that's exactly what I've already proposedI have a very capable, industrial SoC with a modern, embedded GPU (which is significantly more capable than the Mali-400 MP2 included on the MPSoC); all I now need is an FPGA to connect to it. My SoC provides PCIe Gen3x4 so that's what I'm targeting on the FPGA side of things.

author: asmi
author_rank: Super Contributor
timestamp: August 13, 2024, 02:54:01 am
content: Quote from: jars121 on August 13, 2024, 01:57:35 amIn this case you don't really need MPSoC, any "pure" FPGA will sufficient speed and resources would do. Do you have any idea of requirements for the FPGA (speed, resources, specific IO requirements beyond PCIE, etc.)? Maybe once you let us know them, we can be more helpful and specific.

author: Someone
author_rank: Super Contributor
timestamp: August 13, 2024, 08:07:29 am
content: Quote from: asmi on August 13, 2024, 02:54:01 amOr the FPGA devs would question what is the GPU actually needed for? Offloading that compute to the FPGA might fit it into an MPSoC

author: asmi
author_rank: Super Contributor
timestamp: August 13, 2024, 11:08:27 am
content: Quote from: Someone on August 13, 2024, 08:07:29 amConsidering that he mentioned Opengl, I would guess graphics.

author: jars121
author_rank: Regular Contributor
timestamp: August 13, 2024, 11:46:08 am
content: Yes that's correct. We've got an existing suite of graphics which we'd like to carry over to this design, the only change being higher throughput sensor interfaces and tighter timing/determinism requirements requiring an FPGA over an MCU. I know we could bring the graphics side of things into the FPGA as well, but that's a challenge for another time!I've been giving this further thought this afternoon, and I think there might actually be some scope to incorporate a soft-core CPU in the FPGA, which would definitely lead me towards Microblaze/Xilinx. The PCIe variants in the Efinix Titanium/Topaz options offer hardened RISC-V cores as well which is also worth considering.

author: glenenglish
author_rank: Frequent Contributor
timestamp: August 13, 2024, 09:29:57 pm
content: asmi is right, can use any fpga with a transceiver and PCIe facility.And, since you have a SoC there already- you would load the FPGA from the SoC . need minimum 3 lines (PROG, CCLK, CDAT)something like Artix AU7P or Efinix (with its 4 to 16 PCIe lanes and hard PCIe blocks).what sort of money have you set aside for this part ?What is the FPGA going to do ?

author: jars121
author_rank: Regular Contributor
timestamp: August 14, 2024, 12:32:35 am
content: Quote from: glenenglish on August 13, 2024, 09:29:57 pmThe AU7P was certainly the part I was leaning towards. In terms of pricing I'm targeting sub-$100, but as a (very) low volume manufacturer, FPGA pricing seems to be a complete lottery.The FPGA will be doing the following:Interfacing with several moderate frequency, high precision multi-channel ADCs via 16-bit parallel interfacesMulti-channel pulse train measurement (frequency/period, pulse width, duty cycle, etc.)Interfacing with a number of other lower frequency measurement ICs via SPI/I2C for which a soft-/hard-core processor might be a reasonable option.

author: glenenglish
author_rank: Frequent Contributor
timestamp: August 14, 2024, 08:21:12 am
content: sub $100 is very doable in low quantities for the 484 package.sounds ideal.or use the Efinix. it's quite good. I have a $ value where above, I use Xilinx, and below I use Efinix. Xilinx owns a good chunk of Efinix.... and I think is content for them them fill the low end market.Efinix also gives you 10 gig ethernet IP....What's the max sample rate, and total number of bits per second coming off all the converters (IE total flip flops/second)Unless you need heavy mixed signal processing and algorithmic complexity, I've found soft cores suit.The advantage of ZYNQ and MPSoC and Polarfire SoC, over all others is that they boot before the fabric does, and the fabric can be reconfigured on the fly. The others all require some soft or hard cpu config to come from the bitstream.

author: jars121
author_rank: Regular Contributor
timestamp: August 14, 2024, 09:32:24 am
content: I'm honestly really interested in the Efinix, my only concern is how 'new' they are compared with Xilinx, and how much discovery I'm going to have to do, versus years worth of Xilinx forum questions/answers, YouTube videos, forum posts, etc. The Efinix forum isn't particularly active, with a lot of the responses seeming to be 'check our LinkedIn for the latest communications'. For example, the Ti85 seems to be a good fit for this use case, as it offers PCIe, has the hardened RISC-V cores, and has some reasonable packages as well, but I can't seem to determine when it'll be available (with PCIe support) for development and testing purposes. Similarly, the Titanium landing page shows a multitude of packages for a given product, but that product's page (and the product selector guide PDF) only shows 1 or 2 packages as being actually available.In terms of max converter bit rate, the cumulative bitrate would be <500MBit/s.I do like the idea of soft-/hard-core processor configuration independence from the bitstream, but I don't think it'll sway me one way or the other in this instance.

author: glenenglish
author_rank: Frequent Contributor
timestamp: August 14, 2024, 08:14:25 pm
content: Yeah, Efinix is a small company, with constraints on people and resources, I have a pretty close relationship with the factory. A good FAE has this direct relationship. The forum is sort of useful.I'm waiting on Ti85 info right now, which should be , cost wise, an alternative to the Z7010. Yes , package release is staggered. The only hard core actually shipping right now are the Ti375 529 and 1156 packages with the N484 to come.AU7P is an excellent option for the Xilinx familiar. Microblaze in that fabric really screams .... That or MPSoC which is similar in pricing to the AU7P in the smallest device (ZU1CG) . MPSoc gives you giant wide DMA facilities and hard memory controller etc, that, all in all make it a monster. IE Very much all the extra wide bus and DMA etc stuff in MpSoC that makes it a clincher up to 6.6 Gbps transceivers. Unfortunately, if you need 10+ GB transcievers, there is a huge $ step to ZU4 and you can buy a few Ti375 N1156 for the price of a ZU4...Spartan-US doesnt have enough high speed IOs for me to be interested.g

author: jars121
author_rank: Regular Contributor
timestamp: August 14, 2024, 09:12:42 pm
content: Thanks Glen, your input has been excellent and greatly appreciated.I think I've more or less landed on the AU7P (subject to actually building the design and analysing resource utilisation/requirements). The MPSoCs have always interested me as well, but for this particular use case I'd prefer to have the PCIe interface in PL rather than PS (as is the case with the lower end MPSoC devices), and I think Microblaze will be sufficient for the processor side of the design; I think having the heterogenous hardcore processors in the MPSoC would add unnecessary complication.I'll keep an eye on Efinix in the meantime. I've still got quite a long development path ahead, and I'll be starting with the SoC side of the equation, so if the Ti85 (or Topaz line) becomes available in the near future I may well look into it further.

author: glenenglish
author_rank: Frequent Contributor
timestamp: August 14, 2024, 09:25:24 pm
content: YEs, just a footnote, on MPSoC, you can connect the transscievers and IP blocks like PCIe and GigE *directly* to the fabric. I do that for low latency requirements.For the AU7P, the microblaze will run 350-600 MHz depending how configured, and you will love Ultrascale fabric- runs right up to 99% utilizaton without losing speed.Whlile I love MpSoC, if you want to reduce total system complexity, stay with AU7P etc. the MPSoC is a F****** complex beast.Life is simple and many less supply rails required for AU7P (I use two : VddCore and VCCIO 1.8V)- yes two power planes only.FYI Topaz is just lower yield/spec Titanium. I guess they've found something they can do with lower spec chiplets. Or maybe it is a easier cheap TSMC process. but same mask sets.