RISC-V HiFive Premier P550 board general availaility, from $399. - Page 1
Forum section: electronics / general

author: brucehoult
author_rank: Super Contributor
timestamp: December 12, 2024, 12:00:37 am
content: https://x.com/SiFive/status/1866878957598941500This is (along with 3rd party boards, see below) currently the fastest per-core RISC-V SBC available, though sadly only 4 cores, and no vector/SIMD. Fedora's rwmj benchmarked the board at 25% faster than a Pi 4 in building the grub2 RPM. We're going to have to wait for SG2380 to have RISC-V faster than Pi 5 / Rock 5 / Orange Pi 5.https://rwmj.wordpress.com/2024/11/19/benchmarking-risc-v-spacemit-x60-and-others/The link in the announcement takes you to the $499 32 GB board which is (already?) out of stock.16 GB (which is enough for a quad core, IMO) is $399 with "375 in stock, ships tomorrow"https://www.arrow.com/en/products/hf106/sifive-incThe original price for the preview launch of 100 Yocto Linux-based boards in October was $600 for a board with 16 GB RAM, so that's a $200 price drop.The current version comes with Ubuntu 24.04 preinstalled.I ordered a 16 GB Milk-V Megrez for $199 a week ago. They are promising shipping within 30 days of ordering. Also the Megrez is running at 1.8 GHz vs the SiFive board at 1.4 GHz. I'm not sure what is going on there as they both say they're using the EIC7700X.The 8 core EIC7702{X} probably isn't that far away too.Pine64 StarPro64 and Sipeed Lichee Pi 5A using the same SoC have both been announced in some way, but without pricing or availability information on either yet.

author: garrettm
author_rank: Frequent Contributor
timestamp: December 12, 2024, 09:01:58 am
content: I realize this is a development board and primarily intended for embedded systems, but I don't see RISC-V breaking into the desktop/low end server market until they add PCIe slots and ATX/ITX form factors. It would be nice to use existing cases, power supplies, add-on cards, etc. for this platform. I believe AMD was working on getting their newer GPUs to play nice RISC-V systems.It would be nice to have an alternative to x86_64 and eventually x86S (if Intel doesn't go belly up first).

author: brucehoult
author_rank: Super Contributor
timestamp: December 12, 2024, 10:01:51 am
content: Quote from: garrettm on December 12, 2024, 09:01:58 amI'm not sure what you've been looking at for your information, but the HiFive Premier P550 board that is the topic here:- is Mini-DTX- has an ATX power supply connector- comes with a Mini-ITX compliant front panel connector- has a PCIe Gen 3 x16 slot (x4 populated)- has SATA 3 for hard diskThe other board I mentioned with the same SoC, the Milk-V Megrez, is Mini-ITX and allows powering it either via ATX power, or a 12V barrel socket (5.5x2.5mm), if you do want to use the board bare. It also has a PCIe slot and SATA 3.The older dual-issue in-order (the P550 is 3-way OoO) Milk-V Jupiter (July 2024) and HiFive Unmatched (May 2021) are also Mini-ITX boards with a PCIe slot, but PCIe M.2 for SSD rather than the SATA PCs like to use.The Milk-V Pioneer (Jan 2024) is also Mini-ITX and has 2x PCIe slots (x16, x8), 2x M.2 M-Key PCIe slots (4 lanes each), 5 SATA 3, a total of 32 PCIe lanes, 64 2.0 GHz OoO CPU cores, 128 GB RAM in 4 DDR4 channels.QuoteNothing to do with AMD doing anything. There are good open source drivers for AMD video cards and they have been working just fine on RISC-V since the first Linux-capable board in early 2018. Here's a RISC-V machine running an RX 580 on LTT in August 2018 -- it was working six months earlier:With the RDNA 2 boards in 2020, the driver started using Floating Point in the Linux device driver, something which early RISC-V kernels assumed no one would do, so the kernel saved and restored the floating point registers and other state when switching between user processes, but not when switching between a user process and the kernel.Independent developer René Rebe added support for FP in the kernel in mid 2021 (a month after the HiFive Unmatched came out). " took only 10 hours to debug and proof-of-concept patch the Linux kernel to support  additional requirements of AMDGPU for RISCV64 to use the newly arrived RX 6700XT Navy Flounder [graphics card]," Rebe explains of his work, "w additional VAAPI hardware accelerated video encoding on the HiFive SiFive Unmatched board!"A comment on that video says "Good to see it works for you on RISCV. For PowerPC community, it is a bit bumpy."The kernel community moves slowly, but a SiFive employee got FP support in the kernel (and therefore RNDA 2) upstreamed and it was released in 6.10 so people with RNDA 2 boards no longer need to use a patched kernel. The patch had of course been available for years.No work from AMD on this.

author: garrettm
author_rank: Frequent Contributor
timestamp: December 12, 2024, 11:38:12 am
content: You're right, that is a PCIe slot! That weird clip in the center made me think it was something else. This is the first time I have ever seen a clip like that on top of a PCIe slot.I've honestly never heard of DTX, let a lone mini-DTX. So fair enough. But my point still stands: that's a weird form factor that isn't popular in the PC market segment. So people, like myself, would need to buy a case that supports that FF, rather than use something that I already have laying around. But as you've said, there are other boards that support mini-ITX, which is nice to see.I was happy to see that it used a standard ATX PSU connector though. I'm not a fan of the DC barrel plugs. Most external PSU bricks I have encountered often make audible hissing or clicking noises at low power draw. ATX PSUs seem to be better behaved in that regard.The AMD GPU comment was from reading a Phoronix article talking about it. If I can find it, I'll post a link. I wasn't casting aspersions against RISC-V. It may very well have been a 3rd party like Rene that it was talking about fixing something or other, and not AMD directly.All-in-all, I'm hopeful that RISC-V can bring new life to the PC market. Even if only as competition to Raspberry Pi, network appliances, NAS, etc. RISC-V might not be as fast as current high power x86 parts but that doesn't mean it can't compete favorably at lower power draw or in other ways.

author: brucehoult
author_rank: Super Contributor
timestamp: December 12, 2024, 12:01:59 pm
content: Quote from: garrettm on December 12, 2024, 11:38:12 amMini-DTX motherboards are 203mm wide and 170mm deep, while mini-ITX boards are 170mm x 170mm.Mini-DTX should mount straight into any ATX or Micro-ATX case, with holes matching etc. It might or might not fit a mini-ITX case depending on if there is 33 mm extra space -- the holes will match.Refer:https://www.silverstonetek.com/en/tech-talk/wh11_008QuoteIt's not really "fixing". That AMD driver is perhaps the only driver in the universe that uses floating point. I would say that no one expected it. The kernel itself goes to some lengths to avoid FP, in order to keep context switches fast.I haven't looked at the final patch. I hope it's at least being done lazily, so that people not using recent AMD cards don't suffer on every context switch (and people *with* recent AMD cards, on all the other context switches).

author: DiTBho
author_rank: Super Contributor
timestamp: December 12, 2024, 01:58:05 pm
content: Quote from: brucehoult on December 12, 2024, 10:01:51 amI don't know if you know this guy, I think he's avery bad person, who makes a lot of clickbait statements and who exploits Youtube to get paid handsomely via Patreon and then never releases anything.The things he does are almost NEVER merged upstream, both because that guy has such a big ego that everyone is an "idiot" except him, and because he doesn't tolerate any criticism.If he writes a patch and someone (like Linus) tells him it's no good, indicating how he should fix it to be accepted upstream, instead of keeping quiet and fix, he starts breaking their balls and whining like a petulant child, then complaining that "they ignore him and his work".* * *Disgusting guy, frankly, if he is the only one to support that RISC-V SBC, I avoid buying it, I'd rather play with a bamboo abacus

author: brucehoult
author_rank: Super Contributor
timestamp: December 12, 2024, 02:12:15 pm
content: Quote from: DiTBho on December 12, 2024, 01:58:05 pmOf course he is not.As I already said, René diagnosed the problem and demonstrated a patch working, just a month after the HiFive Unmatched was released.He never published his patch, or upstreamed it, and -- as I said -- eventually a SiFive engineer duplicated the work and upstreamed it.