[HN Gopher] Baochip-1x: What it is, why I'm doing it now and how...
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Baochip-1x: What it is, why I'm doing it now and how it came about
Author : timhh
Score : 255 points
Date : 2026-03-11 18:21 UTC (3 days ago)
(HTM) web link (www.crowdsupply.com)
(TXT) w3m dump (www.crowdsupply.com)
| bunnie wrote:
| Hello wonderful people! I'm bunnie - just noticed this is on HN.
| Unfortunately due to timezones I'm about to afk for a bit. I'll
| check back when I can, and try to answer questions that
| accumulate here.
| K0balt wrote:
| Very cool! So there's 5x riscV cores available?
| bunnie wrote:
| Yes, 1x Vexriscv RV32-IMAC + MMU, and 4x PicoRV32's as RV32E-MC
| for I/O processing, configured with extensions to enable
| deterministic, real-time bit-banging without having to count
| clocks.
| K0balt wrote:
| Nice! I love the specialized io processors. Fantastic work!
| alex7o wrote:
| That reminds me a lot of the xmos xcore mcus with 8 cores. I
| am curious what kind of synchronization primitives have you
| added and why?
| bunnie wrote:
| I'm actually working on a comprehensive write up on exactly
| this topic that should be out sometime next week!
| K0balt wrote:
| Just ordered 2 to play with!
| cmrdporcupine wrote:
| Sounds like the Parallax Propeller 1/2 as well.
|
| It's a good model for MCU stuff. There were people pushing
| Chip Gracey (Parallax) to use RISC-V instead of his custom
| ISA when he designed the P2 a few years ago, but he chose
| to do his own thing. Which has made compiler development
| difficult.
| K0balt wrote:
| This seems more on the RPI side rather than propeller,
| propeller was never a really good choice for production
| integration. This looks like it could hold its own in
| many contexts.
| mijoharas wrote:
| Cool project. Why is it called the Baochip/Dabao?
|
| Is it big Bao? Or take-away (just learnt the second meaning), or
| something else?
| JSR_FDED wrote:
| I think it's take-away, or to go. Like when you order some food
| to go.
| bunnie wrote:
| Personally, I love eating "bao" (a style of dumplings), but
| also coincidentally, a homophone of "bao" in Chinese (different
| character Bao , similar sound) has a meaning of "protect;
| defend. keep; maintain; preserve. guarantee; ensure". So it
| means both things to me - one of my favorite foods, and also
| describes the technology.
|
| "dabao" is just a pun on that - means "take-away" or "to-go".
| The dabao evaluation board is basically a baochip in a "to-go"
| package.
| chuckadams wrote:
| That would explain the naming of OpenBao, a fork of Hashicorp
| Vault. Goes with the other fork's name (OpenTofu) as well as
| the meaning you just mentioned.
| bArray wrote:
| > Those with a bit of silicon savvy would note that it's not
| cheap to produce such a chip, yet, I have not raised a dollar of
| venture capital. I'm also not independently wealthy. So how is
| this possible?
|
| What kind of order of magnitude of cost are we talking about?
|
| What are the next steps - is there some service to cut the wafer
| and put into a package for you?
| bunnie wrote:
| The masks alone are single digit millions, but with all the
| design tools and staff costs typically tens of millions is the
| benchmark number for a tape out in this node.
|
| After coming out of the fab, the chips go through probing,
| packaging and reeling.
| crote wrote:
| Can you share something about the subsequent per-chip
| manufacturing costs?
| bunnie wrote:
| Rule of thumb is that a processed wafer from 28nm and older
| is around $3k/wafer and the cost goes up kind of
| exponentially towards the smaller nodes. Also, in general,
| the fab wants you to order a "FOUP" of wafers at a time -
| that's 25 wafers at a go.
| gzread wrote:
| This is about transparency just like the Precursor, right? How
| can I know that my Baochip-1x is really what it says it is?
| bunnie wrote:
| The Baochip is packaged in a form of package that is
| inspectable using IRIS. [1] It does not give perfect
| verification but it's the best I can offer until we have more
| open PDKs.
|
| [1] https://bunnie.org/iris
| luma wrote:
| bunnie your book "Hacking the XBox" taught me how to get started
| on reversing electronics, took the fear out of the process, and
| replaced it with fun. Thanks for the multi-decades long effort
| you've made to make these tools available and accessible and
| approachable, your contributions to the hacker community are
| immeasurable and I cannot say thank you enough.
|
| Thanks man!
| intrasight wrote:
| I didn't know there were partially open source RISC-V. I might
| have missed it in the article, but what was the reason for having
| some parts closed source?
| theParadox42 wrote:
| It's not the RISC-V core itself, it's just some of the
| surrounding architecture to support the CPU, to turn it into a
| SOC. So the USB drivers, the AXI memory interfaces, and the
| analog components, like PLLs for generating clocks, or even the
| IO pad drivers. These components take the fully open RISC-V
| core which works in a simulator and makes it work like a normal
| physical chip would.
| alexisread wrote:
| Great work on the chip, I'm really onboard with the trusted
| computing aim!
|
| Is there a way to bootstrap binary code into the reram? I'm
| thinking being able to 'hand-type' in a few hundred byte kernel
| rather than use a flashing tool
| bunnie wrote:
| The chip comes from the factory with a boot0/boot1 chain that
| is fully reproducible and buildable from source. Developers can
| replace boot1 with their own version, where you could add the
| feature you're thinking about.
| arj wrote:
| It seems it had hardware support for secure mesh. Anyone know
| what that is?
| crote wrote:
| With the right equipment it is possible to probe the _inside_
| of a chip, allowing an attacker to measure or even alter
| internal signals down to the transistor level. Expensive, but
| _very_ useful if it lets you extract a crucial shared secret.
|
| The traditional defense against this kind of invasive attack is
| to put a grid of sense wires on the outermost metal layer, and
| measuring whether it has been tampered with: you can't get to
| the important bits without cutting through the security grid,
| but any kind of modification to the security grid triggers a
| self-destruct.
| chuckadams wrote:
| > What's a banker going to do with the source code of a chip,
| anyway?
|
| Hand it to someone who does know what to do with it. It's not as
| important who initially gets the source so much as having it
| available when it is needed.
| Dani99 wrote:
| Moonton Mobile legend mm level15
| genxy wrote:
| To anyone from crowdsupply listening, please turn down your VPN
| check. I am not stripping my privacy protection to use your site.
|
| *edit, Crowdsupply does a full block on multiple VPN providers.
| There is no way to access their site without turning off your
| VPN.
| anilakar wrote:
| You do realize that violating export regulations is a much
| bigger risk than losing a few individuals relying on snake oil
| security?
| genxy wrote:
| Digikey and Mouser do not do this.
|
| > few individuals relying on snake oil security
|
| Please don't.
| lejalv wrote:
| Can you explain what is the connection between closing the
| site to VPN users and violating export regulations?
| shrubble wrote:
| Wouldn't it require making a purchase and providing a
| shipping address? How would a VPN get in the middle of
| checking the physical address?
| vintagedave wrote:
| This is wonderful! Also what a fantastic partnership that allowed
| adding a new CPU to that die. Kudos to them.
|
| I had a lot of trouble finding out which open source license
| applies. Wikipedia's RISC-V page doesn't seem to say; its
| citation for being released under open source doesn't seem to say
| which one either.[0] Could be wrong. Exhausted after working all
| day. But it's not front and center...
|
| On the RISC-V site I thought it might be more prominent too but
| if it is I missed it. I found some docs there licensed Creative
| Commons. Is that the license for the entire CPU? Even layouts and
| everything that is past the ISA to actual silicon?
|
| [0] https://www.extremetech.com/computing/188405-risc-rides-
| agai...
| duffmancd wrote:
| RISC-V is a family of instruction sets (which have various
| chips implementing them). Think "X86-64". It looks like the
| baochip-1x is using the VexRiscv CPU. The HDL is available here
| under MIT: https://github.com/SpinalHDL/VexRiscv
| the_biot wrote:
| Why the few closed-source components on the system? You mention
| the bus, USB PHY etc -- are those things harder to design than
| the CPU core?
| 15155 wrote:
| They are likely licensed IP.
| bunnie wrote:
| In general, things that are not strictly digital (PHYs,
| regulators, PLLs, ADCs) contain significant amounts of foundry
| IP that would be hard to release as open source. But also, some
| parts of the chip, for example the AXI bus fabric, were
| licensed simply as a risk reduction measure. If the bus fabric
| is bad, you've wasted millions of dollars on a mask set with
| little recourse. I tried to pull in some open source AXI
| fabrics and it wasn't pretty...a lot of rework required and
| even then still some bugs made it through to tape-out. Over
| time more and more of this can be opened but it all takes time,
| money, and people willing to do it.
| awesomeusername wrote:
| I run a hardware company now (thankfully in the age of AI), as a
| direct consequence of reading Bunnies book 'hardware hacker'
|
| Thank you Bunnie.
| hedgehog wrote:
| Bunnie did a really good talk a couple months ago that has more
| of the background beyond what's in the blog post:
|
| https://www.youtube.com/watch?v=H5CR-7TJtm0
| stavros wrote:
| Wait a minute, why can't I reply to bunnie's top-level comment?
| Anyway, here's what I wanted to say:
|
| Adding your CPU to another company's silicon is a genius move,
| well done. I wonder why companies don't sell their spare die
| space to others, is it because of trust/risk?
| bunnie wrote:
| Crossbar is unusual to start with in that they wanted to do
| open RTL - so for starters, there's to a first order no
| companies even willing to discuss open RTL designs. Beyond that
| - mainly risk. I had to pinky swear that whatever I added would
| not break the chip, cause timing closure issues, delay the
| schedule, consume too much area or power, impact yield, I had
| to run my own validation and review program while meeting their
| dev methodology, etc. etc. I had to exercise an enormous amount
| of self-restraint to not push harder and do more interesting
| things as it was. It's very hard to build up inter-personal
| trust, and they had to take a calculated risk letting a schmuck
| like me potentially foul up a multi-million dollar mask set.
| Hats off to them for making that bold decision, it would have
| been easier to say nope, too risky, no benefit, cut it from the
| code base.
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