VexRiscv
sdspi
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VexRiscv
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Need help to build a RISC-V Processor on Artix-7 FPGA: Final Year Engineering Project Guide
With LiteX you can synthesize a VexRiscV processor. You can run Linux on it. The toolchain is pretty easy to use, as long as you use Xilinx Vivado to compile to gateware.
- RISC-V with AXI Peripheral
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Intel discontinues Nios II IP
I don't get what's going on with licensing and device support. I'm missing something here perhaps, but we use Cyclone 10 GX onwards and Quartus Pro so I don't have enough context maybe. Have you considered swapping your Nios ii to a VexRISCV as a side note? At ~1 Dhrystone MIPS/MHz it's roughly double that of the Nios V, for very few resources. All open source too. None of the migration documentation support though, so I can't judge how hard it would be.
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How Much Would It Cost For A Truly Open Source RISC-V SOC?
If you use LiteX to generate a VexRiscV system-on-a-chip, you can include an open source DDR DRAM PHY. This works on Xilinx Spartan-6, Spartan7Artix7/Kintex7/Virtex7 FPGAs, and Lattice ECP5 FPGAs. DDR/LPDDR/DDR2/DDR3 depending on the FPGA.
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Which FPGA for getting into RISC-V?
Something like https://github.com/SpinalHDL/VexRiscv will take far fewer
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Faster CRC32-C on x86
A CPU built around the Gentoo philosophy would look like https://github.com/SpinalHDL/VexRiscv ;). Don't want an MMU? Fine. Need a larger RAM interface? You got it. Barrel ALU for DSP? Sure.
Interpreted languages work by consolidating all of the optimization effort in the interpreter. This is similar to how CPUs work now, instead of extremely specific optimizations that are hard to create distributed among all code we use very general optimizations that push the limits of mathematics that is centralized in a CPU.
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Itanium had a lot of contemporary issues that made it not work. I would certainly blame Intel's business practices and reputation for a large part of it. There are likely niches for such processors. The VLIW is useful for DSP or graphics. Indeed, the only extant VLIW (that I know of) processor is the Russian Elbrus. I think the VLIW is only included to let them reuse a lot of the core logic of the CPU to drive a DSP engine, useful for radar and scientific simulation, though the sci sim would probably use commercial hardware which would be faster.
It works on GPUs because they're doing DSP, basically. We could have weirder topologies for GPUs however, like a massive string of ALUs driven off an embedded core, so you try to kachunk all your data in a single clock domain after configuring the ALU string.
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Looking for a suitable open-source RISC-V for an embedded project
4) https://github.com/SpinalHDL/VexRiscv
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What do think of Chisel HDL? is it worth learning over Verilog/SystemVerilog?
I really like Chisel HDL or any other new HDL languages like SpinalHDL or migen b/c it allows you to create some very complex yet modular designs. See VexRiscv or LiteX for instance. Languages like this exist b/c there is a need for it, but I wouldn't say that you should learn these new languages over verilog. All these languages output verilog/VHDL for now, but there is work being to done eliminate the need for outputting verilog; eventually, Chisel will output an open source CIRCT IR. Hope is to get EDA vendors to support this IR which I'm sure will take a while. For now, you should definitely learn Verilog or VHDL before Chisel.
- Looking for help with RISC-V softcore and VHDL
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Thermal sensor mlx90640 with Nexys 3 fpga
I'd recommend giving vexriscv a look. It'll handily fit on your FPGA, leaving plants of room for I2C, VGA output, and whatever multiplication you end up wanting to do. It's very easy to get set up, and their example "briey" SOC even has VGA output already, but not hardware I2C (though you could easily bitbang it with the core). Adding in I2C via a "plugin" should be trivial.
sdspi
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C++ Verification Testbench Best-Practice Resources?
I have built a lot of open-source C++ tooling for design verification. You can find a lot of my C++ models posted on my Github. Example C++ models include: UART, SPI/DSPI/QSPI Flash, SD-Card (SPI-based interface), VGA Video, Ethernet MDIO, PS/2 mouse, OLED display, SDRAM and more. (I've even simulated PLLs using C++ models ...) I have also written extensively about doing so at ZipCPU.com.
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Envisioning the Ultimate I2C Controller
You mean ... sort of like I did in this project? I implemented an SPI based controller, where the controller took care of all the bit-banging for you, but the CPU still needed to issue the commands as appropriate for the protocol?
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SoC FPGA design to ASIC
How about an SD card controller? I know I have a SPI based SD card controller, but the SDIO isn't that much harder. If you look hard enough you can find open source SDIO controllers.
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CPU DESIGN
There are also open source versions of many of the pieces you will need. I now use an open source crossbar interconnect for most of my designs. I use AutoFPGA to connect all the pieces together. I mentioned my flash controller above, but I also have a SD Card controller I've used quite successfully. I've also posted a UART to Wishbone bridge and discussed network debugging, both of which I use routinely with the ZipCPU. If for no other reason, these components allow me to load or update software on my CPU even after it's been placed into an FPGA. Of course, many of those components are tied to a Wishbone bus infrastructure. You may find you need a bridge of some type to connect different buses structures together--memory naturally tends to operate at one width and clock, video at another, and your CPU at another, so it helps at times to have a universal bus adapter kit handy.
What are some alternatives?
neorv32 - :rocket: A tiny, customizable and extensible MCU-class 32-bit RISC-V soft-core CPU and microcontroller-like SoC written in platform-independent VHDL.
biriscv - 32-bit Superscalar RISC-V CPU
ibex - Ibex is a small 32 bit RISC-V CPU core, previously known as zero-riscy.
wb2axip - Bus bridges and other odds and ends
RISCV-FiveStage - Marginally better than redstone
dpll - A collection of phase locked loop (PLL) related projects
nybbleForth - Stack machine with 4-bit instructions
darkriscv - opensouce RISC-V cpu core implemented in Verilog from scratch in one night!
Rudi-RV32I - A rudimental RISCV CPU supporting RV32I instructions, in VHDL
dromajo - RISC-V RV64GC emulator designed for RTL co-simulation
videozip - A ZipCPU SoC for the Nexys Video board supporting video functionality