[HN Gopher] XiangShan open-source 64-bit RISC-V processor to riv...
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XiangShan open-source 64-bit RISC-V processor to rival Arm
Cortex-A76
Author : watchdogtimer
Score : 268 points
Date : 2021-07-05 13:24 UTC (9 hours ago)
(HTM) web link (www.cnx-software.com)
(TXT) w3m dump (www.cnx-software.com)
| eunos wrote:
| I don't know whether it is possible with chip development or not.
| But I really hope that this project will enable numerous amount
| of derivative chips just as Linux kernel allows multiple distro.
| That means IoT/GPU/CPU/etc chips need not to start from scratch.
| In addition, having similar foundations might help fabs
| manufacture those chips swiftly.
| goodpoint wrote:
| That's the whole point of open source hardware.
|
| Unfortunately most of the licenses used are not reciprocal and
| this does not encourage building ecosystems.
| yorwba wrote:
| In the readme, they list three components that were sourced
| from other open-source projects: https://github.com/OpenXiang
| Shan/XiangShan/blob/master/READM...
|
| So it seems like there already is a little bit of an
| ecosystem.
| ekiwi wrote:
| I think the hardest problem is contributing changes back
| upstream. With hardware, people are a lot more paranoid
| about introducing new bugs and I feel like that sometimes
| makes collaboration a lot more difficult.
| yorwba wrote:
| In a writeup on WeChat
| https://mp.weixin.qq.com/s/MAkxKZ1eS4UwBkvgD91Xng , Prof.
| Bao Yungang mentioned that one reason for starting the
| project was that they felt the barrier of contributing to
| Berkeley's BOOM https://boom-core.org/ was too high,
| pointing out that only 8 people contributed more than 100
| lines.
|
| So at least they're aware of the problem, although that
| doesn't guarantee that they'll fare better in terms of
| attracting outside contributions.
| WanderPanda wrote:
| Oh man it's starting, we will have to learn Chinese to
| get access to the whole picture of all the information
| out there. Some weeks ago I already heard that there are
| really good VUE.js sources in the Chinese web. This is
| quite terrifying, it seems like it is only a matter of
| time until state of the art scientific papers will only
| be available in Chinese :(
| lucian1900 wrote:
| So many of us speakers of other languages had to learn
| English. Now you'll just have to join us in learning
| Chinese. It's not that hard, just very different.
| throwawaysea wrote:
| I guess I view it as democratizing rather than
| terrifying, particularly when there is broader acceptance
| of research and papers in non-STEM areas from outside the
| western sphere. For instance, psychology, history,
| linguistics, social fields (sociology, gender studies,
| etc) are all heavily tainted by a Western
| worldview/ideology bias due to the immense dominance of
| Western universities and academic spheres. Having a
| competing ecosystem is going to improve the diversity of
| thought we see.
| thiagoharry wrote:
| Well, the good part is that more people speaks Chinese
| than English. Less people will suffer with language
| barriers to knowledge.
| jcranmer wrote:
| > Well, the good part is that more people speaks Chinese
| than English. Less people will suffer with language
| barriers to knowledge.
|
| That's actually not true. More people speak Mandarin as a
| _first_ language than English (which is third, behind
| Spanish as well). However, far more people speak English
| as a second (or third) language than do as a first
| language, so that English is actually the most widely
| spoken language.
| krastanov wrote:
| For those like me that thought this is wrong because of
| how big India is: according to the last census, only
| around 15% speak English as first/second/third language.
| fspeech wrote:
| I suppose the author Jean-Luc Aufranc can access Chinese
| because he linked to a most fascinating account of the
| development process https://www.zhihu.com/question/466393
| 646/answer/1955410750 The key to getting where they are
| is commitment to developing design flow and tools that
| allow for fast iteration to explore and verify design
| changes.
| yorwba wrote:
| TFA links an article in the German c't magazine as the
| source, which also links to the Zhihu thread:
| https://www.heise.de/news/Offengelegter-RISC-V-Chip-aus-
| Chin...
| krastanov wrote:
| I think you have already been underestimating the quality
| of resources available in French, Russian, German, and
| others, that do not exist in English. Just as a single
| example, the math section of the French Wikipedia was
| distinctly superior to the English one when I was in
| college (2012).
| zokier wrote:
| > But I really hope that this project will enable numerous
| amount of derivative chips just as Linux kernel allows multiple
| distro. That means IoT/GPU/CPU/etc chips need not to start from
| scratch
|
| I feel this has been already happening with ARM.
| PragmaticPulp wrote:
| Very cool to see a team of 25 students put this together and get
| prototypes made. I wish opportunities like these were available
| back in my college days.
|
| The headline is getting slightly ahead of the actual performance.
| Reaching Cortex-A76 performance is their goal after many more
| iterations. Their current implementation is not there yet, but
| that shouldn't detract from the magnitude of their achievement
| and their contribution to the open-source world:
|
| > This culminated with an 8-core prototype built based on Yanqihu
| (Yan Qi Hu ) architecture using TSMC's 28nm process with the
| processor running up to 1.2 or 1.3 GHz that should be taped out
| this month. But plans have been made to tape out a new prototype
| based on Nanhu (Nan Hu ) by the end of the year, using SMIC's
| 14nm process allowing up to 2 GHz frequency, and further
| iterations of the architecture will aim at rivaling Arm's
| Cortex-A76 processor.
|
| RISC-V is an exciting development in the SoC world. We're
| starting to see some of HiFive's boards trickle out into the
| wild. The performance is good, but it's not quite as
| groundbreaking as many of the headlines make it out to be. The
| most exciting part of all of this is that ARM has more
| competition and we get to see some open-source contributions like
| this.
| throwawaysea wrote:
| For someone unfamiliar with how the overall process works,
| what's the road from this design to seeing this power laptops
| or desktops available to consumers? It isn't clear to me, for
| example, what else needs to be designed around this - a
| motherboard? Will software "just works" since it is using a
| known instruction set architecture?
| ethbr0 wrote:
| Are there higher level abstraction efforts in the linux kernel
| to prevent a hypothetical custom RISC-V diversity explosion
| from ending up quite as messily as custom ARM did?
|
| Afaict, most of the ARM ugliness was around non-"CPU" SoC
| components. But it definitely seemed like kernel code
| organization wasn't ready for a 10x (or 100x) explosion of
| popular SoCs.
|
| And the entire point of open sourced RISC-V cores is that they
| would enable even more chip diversity, no?
| voakbasda wrote:
| There have been discussions about this, and my conclusion is
| that there definitely _could_ be a problem on the order of
| ARM's. With luck, RISC-V will learn from history and not doom
| itself to repeat the same mistakes.
| Pet_Ant wrote:
| Is there an existing standard that board implementations
| can rally around? Something like OpenBoot? Make it a
| defacto standard.
| goodpoint wrote:
| The RISC-V ISA specifically allows for custom extensions.
|
| Unfortunately, the licensing model does require the
| implementations to be FLOSS. This encourages creating a lot
| of closed stuff with different and incompatible extensions.
| rjsw wrote:
| Whether RISC-V ISA extensions are allowed or not is
| unrelated to the problems seen with ARM SoCs putting
| peripheral devices at different addresses.
| a9h74j wrote:
| Could a device table [for on-chip peripherals] be put
| right on chip?
| formerly_proven wrote:
| Yes, that's a devicetree. Those can be tacked onto the
| kernel image or dynamically loaded from the chip's
| firmware (which most likely gets it from the firmware
| flash).
| goodpoint wrote:
| Sure, but the question was about diversity explosion in
| general.
| rektide wrote:
| > I wish opportunities like these were available back in my
| college days.
|
| I'm forgetting the source, but some book I read discussed some
| period of silicon valley as a place where colleges quite
| routinely exposed students to chip-making. It sounded like the
| fabs of the area greatly supported these efforts. I'm not sure
| where I read it but it's stuck with me across many years,
| always strongly affirming my belief that people, when given
| exposure to how & means to do, begin many great things.
| zsmi wrote:
| I'm sure students in the valley have been routinely exposed
| to VLSI chip-making, and actually making ICs, since at least
| the early 90s. I know I was.
|
| The main problem is there are only so many universities with
| so many sections therefore quite a lot of students don't get
| exposure, even within a given EE department. And even if they
| could offer it to all students, many wouldn't enroll, as
| you're basically doing this class constantly for like a year,
| for not that many credits relative to the time spent, as it
| sucks down just tons of hours as one gets familiar with all
| the nitpicky details that one needs to know. And as one
| learns to deal with the joy that is CAD tooling.
|
| However, in my opinion, the experience in invaluable. And
| students that can pass that course, with a successful chip in
| hand, are hand picked by employers. We sure do.
|
| EE272 at Stanford actually started to post their flow.
| Another benefit of the open source PDKs.
|
| https://code.stanford.edu/ee272/skywater-digital-flow
|
| There are actually many interesting student designs out
| there. For example this OoO RV64GC RISC-V core from Berkeley:
| https://chipyard.readthedocs.io/en/latest/Generators/BOOM.ht.
| ..
| shard wrote:
| Not sure when GP went to college, but Caltech students were
| able to submit projects to MOSIS shuttle runs for a chip
| design class over 25 years ago.
| andrekandre wrote:
| i love these names: they are very intel-like
|
| Yan Qi Hu - yangqi lake Nan Hu - south lake
| goodpoint wrote:
| """The RISC-V core has been developed with Chisel language ...
| released under a Mulan PSL v2 license"""
| [deleted]
| the-dude wrote:
| https://opensource.org/licenses/MulanPSL-2.0
|
| Which apparently grants a _patent_ license.
| amelius wrote:
| Only for the patents owned by the contributors.
| hvis wrote:
| Sounds similar to Apache 2.0 License.
| alexmcc81 wrote:
| More info: https://choosealicense.com/licenses/mulanpsl-2.0/
| jbluepolarbear wrote:
| This is really cool. I hope this leads to more innovation in the
| open source phones, computers, and game hardware.
| throwaway4good wrote:
| Impressive work by an university group.
|
| Perhaps also a testament to what you get in terms of
| productivity, if you use a more modern platform / language
| (Chisel/Scala).
| xwolfi wrote:
| It's not yet in computers, let's see if they dont face real
| world struggle in actual industrialization for the mass market
| first (or if they even manage to reach this point).
|
| Productivity goes from design to client satisfaction :) A very
| productive team is not a team who prints an open source
| document nobody can use !
| rowanG077 wrote:
| This is a university project. It will never be in "real"
| computers. At least not as a result of the doing of the
| university. Someone else could take this design and put it
| into "real" computers.
| tyingq wrote:
| MicroMagic is pretty interesting to me in the RISC-V space:
| https://arstechnica.com/gadgets/2020/12/new-risc-v-cpu-claim...
|
| They are getting perf-per-watt numbers that are ahead of
| everyone...albeit with a single core and no real 3rd party
| verification.
|
| Some of the group had worked on Sparc at Sun, and they had
| previously sold themselves to Juniper for $260M, then regrouped
| some time afterwards.
| MobiusHorizons wrote:
| The previous discussion of that article on HN seemed to point
| to those numbers being totally unsuported.
| https://news.ycombinator.com/item?id=25262834
|
| Obviously I would love those perf-per-watt numbers to be
| correct, but it doesn't seem like they have shown it yet.
| mnurzia wrote:
| It's worth noting that Micro Magic's design tools are likely
| what allowed them to claim these numbers. Some of the claims
| they make about their software are pretty impressive, but it
| mainly boils down to intelligent placing/routing techniques
| that mirror fully custom hand-made silicon designs but are
| actually designed by the computer:
| http://www.micromagic.com/datasheets/PDFs/DPC_3page_Layout.p...
|
| It seems like their design workflow is ahead of the rest of the
| field.
| jhvkjhk wrote:
| For those who don't know, Xiang Shan is a famous hill in Beijing,
| best known for red leaves in autumn.
| clubdorothe wrote:
| In Taipei (Taiwan), it is the name of a mountain where most of
| the photos shots are taken.
|
| It's a great small hike you should do if you visit the city.
| Start the hike around 4.30pm to catch the sunset.
| https://taiwangoldcard.com/images/taiwan-unsplash.jpeg
| gibolt wrote:
| It is written Xiang Shan , which means elephant mountain.
| There are elephant statues on the hike.
| mytailorisrich wrote:
| The one in Beijing is Xiang Shan , Fragrant Hill. This
| project is the same.
| contingencies wrote:
| https://en.wikipedia.org/wiki/Fragrant_Hills
| zadokshi wrote:
| Yes but the Chinese characters make it clear that it's not a
| reference to Taiwan. That mountain trail in Taiwan is
| breathtakingly awesome though.
| magicsmoke wrote:
| The confusion over Chinese names and logograms is pretty
| funny considering that in Chinese, western names are
| written with a set of phonetic logograms and losing that
| spelling information with latin/cyrillic characters makes
| it hard to tell if the name was English, Italian, German,
| or Russian.
|
| Personally, it would be great if names on western websites
| are written with logograms in parenthesis and names on
| Chinese websites are written with spelled characters in
| parenthesis. Just another one of those weird cross-cultural
| areas of friction.
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(page generated 2021-07-05 23:00 UTC)