Debian Riscv64 port in mid 2019 • Hacker News Board

Re: Debian Riscv64 port in mid 2019

#21

Post by snvzz » Wed, Jun 19, 2019, 1:07 PM UTC

sschueller wrote: post #3

Any "Pi'esc" boards available yet? I would love to run Buster on a RISC-V board. Seeedstudio has an "Arduino'esc" RISC-V board for around USD 30 which looks very interesting. [1] This board [2] also looks very interesting but is around USD 1000 and I can't find any comparisons on performance to a "regular" PC. I know these things are like comparing apples to oranges but I would like to know how for example a browser…

The cheapest are indeed the devices based on the sipeed chip.

If that's insufficient, your best bet is to get a risc-v capable FPGA.

Re: Debian Riscv64 port in mid 2019

#22

Post by snvzz » Wed, Jun 19, 2019, 1:07 PM UTC

meuk wrote: post #10

asveikau wrote: post #8

Earlier quoted context omitted.

Whoa, I had considered the unleashed board to play around with and bookmarked it, but they are not very overt with the price. I didn't realize it was $1000 USD. You have to click through twice to discover it.

You might consider the HiFive board. It's around 50 dollar, a more appropriate price for something to play around with.

The chips used in the hifive board are not available for sale anywhere. They're apparently a one-off run for the hifive board specifically.

Therefore, they're not a good choice to base a project on.

I do look forward at low power microcontrollers based on risc-v with some actual commitment to continued availability.

Re: Debian Riscv64 port in mid 2019

#23

Post by ncmncm » Wed, Jun 19, 2019, 1:11 PM UTC

josteink wrote: post #5

Basically LLVM is now a dependency of equal importance to GCC for Debian. Hopefully this will help motivate expanding architecture-support for LLVM, and by proxy Rust.

Godbolt shows that Clang is a lot more aggressive with use of "cmov" -- conditional move instructions.

When the Spectre and Meltdown family of security debacles surfaced, cmov was promoted as a way to choke off speculative execution. But that suggests, also, that cmov would be bad for performance in places where cross-process security isn't a concern.

Did something important change, or did I misunderstand? Maybe only cmov memory -> register blocks speculation?

Re: Debian Riscv64 port in mid 2019

#24

Post by ncmncm » Wed, Jun 19, 2019, 1:21 PM UTC

stan_rogers wrote: post #16

sschueller wrote: post #3

Any "Pi'esc" boards available yet? I would love to run Buster on a RISC-V board. Seeedstudio has an "Arduino'esc" RISC-V board for around USD 30 which looks very interesting. [1] This board [2] also looks very interesting but is around USD 1000 and I can't find any comparisons on performance to a "regular" PC. I know these things are like comparing apples to oranges but I would like to know how for example a browser…

Just informational: the esc sound meaning "-like" is rendered as esque . We "borrowed" it from the French, and we're not giving it back.

Similarly to "isch" from German, which we filed the serial numbers off of, and respelled "ish". For some reason we are squeamish about doing that to French.

Perhaps ironically, we took squeamish from French escoymous, but substituted "our" suffix.

Re: Debian Riscv64 port in mid 2019

#25

Post by 0815test » Wed, Jun 19, 2019, 1:23 PM UTC

boomlinde wrote: post #14

kstenerud wrote: post #12

I'm surprised at how m68k was rescued from oblivion in 2013... Who is using it?

I suspected that it had something to do with ColdFire. It seems that was partly true, but another interesting factor was apparently ARAnyM (an Atari 68k ST/TT/Falcon emulator) which can conveniently run a Linux system: https://grep.be/blog/en/computer/debian/m68k/arrakis/

There's also the Apollo core used in the Vampire accelerator, that's much faster than anything else m68k, and even faster than ColdFire.

Re: Debian Riscv64 port in mid 2019

#26

Post by ncmncm » Wed, Jun 19, 2019, 1:25 PM UTC

I am waiting until the Bitmanip extension lands to get excited about RISC-V: https://github.com/riscv/riscv-bitmanip

Just can't live without that popcount.

Re: Debian Riscv64 port in mid 2019

#27

Post by pedrocr » Wed, Jun 19, 2019, 1:27 PM UTC

ncmncm wrote: post #19

They say Rust support is blocked by having no RISC-V backed for LLVM, and no Rust Gcc front-end. But I thought there was a working Gcc front-end, just without the borrow checker, which is superfluous for code generation. Maybe it is for an old version of the language, and can't build the current library?

This is probably what you mean:

https://github.com/thepowersgang/mrustc

It's still a work in progress, with only x86 even supported. It's not a GCC frontend, it generates C, and is based on an old version of rust (1.19). Right now I think it's only useful to bootstrap rust, but that doesn't help you get a backend for another architecture.

Re: Debian Riscv64 port in mid 2019

#28

Post by opencl » Wed, Jun 19, 2019, 1:45 PM UTC

carlosedp wrote: post #4

sschueller wrote: post #3

Any "Pi'esc" boards available yet? I would love to run Buster on a RISC-V board. Seeedstudio has an "Arduino'esc" RISC-V board for around USD 30 which looks very interesting. [1] This board [2] also looks very interesting but is around USD 1000 and I can't find any comparisons on performance to a "regular" PC. I know these things are like comparing apples to oranges but I would like to know how for example a browser…

The Unleashed board has a performance similar to a Raspberry Pi 3 in cpu terms but it's biggest bottleneck is that the SD card is running on a SPI bus where it gets something like 2MB/s. This is due to having the complete SOC as opensource and the SD card association not allowing open source IP for it's interface.

It does have gigabit ethernet and there's also an expansion board with SATA and PCIe but that's another $2000 because it's using an enormous FPGA.

Re: Debian Riscv64 port in mid 2019

#29

Post by pjc50 » Wed, Jun 19, 2019, 1:46 PM UTC

yjftsjthsd-h wrote: post #11

meuk wrote: post #10

Earlier quoted context omitted.

You might consider the HiFive board. It's around 50 dollar, a more appropriate price for something to play around with.

The hifive is marketed as an arduino-like, but at 320mHz it seems like it should be able to run a stripped-down Linux distro. Not fast , but if Linux can run on puny MIPS boards...

It doesn't appear to have any DRAM, so you'd have to find a linux capable of running in 16 (sixteen) kilobytes of onchip SRAM. Without an MMU.

Re: Debian Riscv64 port in mid 2019

#30

Post by boomlinde » Wed, Jun 19, 2019, 1:47 PM UTC

0815test wrote: post #25

boomlinde wrote: post #14

Earlier quoted context omitted.

I suspected that it had something to do with ColdFire. It seems that was partly true, but another interesting factor was apparently ARAnyM (an Atari 68k ST/TT/Falcon emulator) which can conveniently run a Linux system: https://grep.be/blog/en/computer/debian/m68k/arrakis/

There's also the Apollo core used in the Vampire accelerator, that's much faster than anything else m68k, and even faster than ColdFire.

Yes, but that doesn't explain the m68k porting effort of 2013. The Apollo core doesn't have an MMU so it won't run Linux.