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Doluon Chisel: A Modern Hardware Design Language

> The HLS generated verilog is name mangled

Chisel, SpinalHDL, Clash, Migen, Amaranth aren't HLS

Most of the time, if you get some verilog out of those tools with mangled names, it can be because of bad coding practice.

Here is some examples about how to preserve good names for SpinalHDL : https://spinalhdl.github.io/SpinalDoc-RTD/master/SpinalHDL/S...

Doluon Chisel: A Modern Hardware Design Language

> FWIW, that's not true, you can write it as one:

While technicaly you are right, i think you missed the spirit of what the doc was saying.

You may write it all in a single process, but you will always have duplicated code blocks, especialy if those 3 types of hardware (ff,ff with reset, comb) share assignements with the same condition.

Doluon Chisel: Constructing Hardware in a Scala Embedded Language

On this talk : - https://youtu.be/f-b4QOzMyfU?t=300 - https://youtu.be/f-b4QOzMyfU?t=492 => yes and no

The industry lack's of wide profiles (hardware engineer with good software understanding) is really hurting any new innovative HDL

Doluon Chisel: Constructing Hardware in a Scala Embedded Language

Checkout SpinalHDL it keep much more of your hardware description semantic inside the generated Verilog

Doluon Chisel: Constructing Hardware in a Scala Embedded Language

Wrong, it was implemented from scratch. Look the same, but was implemented in a very different philosophy. SpinalHDL is from my opinion much better.

Doluon An FPGA-friendly 32-bit RISC-V CPU implementation

I was exactly in the same mood some years ago, until i triey one of those HDL alternative.

Doluon An FPGA-friendly 32-bit RISC-V CPU implementation

Honnestly, i haven't realy think about it. Not a constraining one, but more something like :

Do what ever you want with it, but if you find a bug, please tell me, and if you use it in a project which has a lot of money, please, share a bit with opensource guys, don't be too greedy ^^

Doluon An FPGA-friendly 32-bit RISC-V CPU implementation

Cached an uncached memory access are currently staticaly specified by range :

https://github.com/SpinalHDL/VexRiscv/blob/master/src/main/s...

From 0xF000000 to 0xFFFFFFFF access will be uncached.

Doluon An FPGA-friendly 32-bit RISC-V CPU implementation

Yes it would be, it is very easy to retarget the CPU to another memory bus.

Then the Wishbone one isn't "perfect" as it can't map memories which have latencies without performance penality. It would be oky for the data bus of the cpu with or without cache, but for the instruction, without instruction cache, peak CPI would be divided by the memory latency.

Doluon An FPGA-friendly 32-bit RISC-V CPU implementation

Yes i agree, would have been more convenent to use the integrated jtag of the FPGA, but i focused on making an universal solution first :)

Doluon An FPGA-friendly 32-bit RISC-V CPU implementation

Are you sure it need a license ? I were thinking that AXI usage is royalities free (https://en.wikipedia.org/wiki/Advanced_Microcontroller_Bus_A...)

Doluon An FPGA-friendly 32-bit RISC-V CPU implementation

They aren't made for external com

Doluon An FPGA-friendly 32-bit RISC-V CPU implementation

Yes a standard would be great, with all the feature provide by those embedded HDL, but i'm realy not sure the industry could make it. #systemverilog

Doluon An FPGA-friendly 32-bit RISC-V CPU implementation

Yes kind of, SpinalHDL is a from scratch fork

Doluon An FPGA-friendly 32-bit RISC-V CPU implementation

Yes, silicon implementation provide the JTAG, but it's very likely their implementation will not be reusable for FPGA project (including JTAG debug things) because of their over complicated (but powerfull) solutions which would consume way to much area and restrict the FMax.

Then this specific VexRiscv ecosystem also provide a basic SoC with an multi master AXI4 inteconnect, SDRAM controller, embedded ram, APB3 interconnect, some slave like GPIO, UART, Timer, VGA. It's not incredible, but it's already a starting point ^^ See https://github.com/SpinalHDL/VexRiscv#briey-soc