On Saturday 2. May 2015 17.07.57 Manuel A. Fernandez Montecelo wrote:
Speaking of openness/FSF-endorsability, and having into account that the current focus is to go ahead with what is already planned like the A20, with which I fully agree (so please don't take this as a demand, just as showing interest) -- would it be feasible in the near future to have OpenRISC or RISC-V (or RISC-V-based lowrisc, when ready)?
I imagine that it depends on things like availability of hardware versions of CPUs for these architectures. I recall that there was a board for OpenRISC that used an FPGA, and there was also a fundraising campaign for an ASIC version of, I think, the OR1200 which didn't succeed. So it may be the case that an FPGA solution is the only remotely near-future option, and that brings a lot of other issues.
There's also the distinction between plain CPUs and SoCs. I don't really follow what goes on around these things, but I recall that the people who were developing the Milkymist One hardware were aiming to deliver an SoC solution based on the LatticeMico32 core:
https://en.wikipedia.org/wiki/M-Labs
I don't know what the situation is with OpenRISC and SoCs.
With the FPGA stuff, a significant concern has been the need for proprietary tools to actually deploy the hardware designs. It appears that some work is coming to fruition to eliminate such tools for some FPGA products:
http://www.clifford.at/yosys/about.html
Almost none of the disadvantages cited for Intel or NVIDIA SoCs apply (NDAs, binary blobs, power issues). Everything is fully open in the case of those processors, and the toolchains are based on the usual GNU/Linux ones (GNU GCC, glibc, etc) and mostly ready (they could use some help with upstreaming, but that's another issue). Unless there is a problem with finding factories able to build them, I don't know if there is any disadvantage compared to ICubeCorp IC3128 and Ingenic JZ4775?
Maybe performance might be an issue if the FPGA route is chosen. Otherwise, it's the availability of "proper silicon" versions, I guess.
In the case of OpenRISC, there is even a Debian port half-ready [1]. I guess that Ingenic's will already work with the Debian mips/mipsel port, but I think that for ICubeCorp's all of the software distribution would have to be created from scratch.
[1] https://people.debian.org/~mafm/posts/2015/20150421_about-the-debian-
gnulinux-port-for-openrisc-or1k/
That's an interesting report! Certainly, OpenRISC can hopefully use a lot of the existing MIPS-targeted software without significant modification.
Paul