4 ms·

I suppose in theory the FPGA could contain a hidden CPU that has full read/write access to the FPGA program. All of them do at this point. It isn't hidden. Y

I suppose in theory the FPGA could contain a hidden CPU that has full read/write access to the FPGA program. All of them do at this point. It isn't hidden. You can't buy a large FPGA without an ARM core in it. The ARM cores all have an opaque signed blob running in EL3 that you can't replace. This isn't a soft core on the fabric; it's dedicated silicon. And it has access to the ICAP (internal configuration access port) on Xilinx devices, and the equivalent on all the other manufacturers.

asddubs 2y ago
What is it for?
- dailykoder 2y ago
  The ARM Core? It's usually used for anything software you need and the FPGA gets used for any domain specific circuit for signal processing and what not in hardware. The ARM core usually runs a linux or any other OS and is used for communication with other devices. It's just able to run at a higher frequency than most soft-cores, because it's a fully integrated and optimized circuit. So in theory that's a nice thing and gives you more space for custom circuits on the programmable logic part. PS: The latest polarfire chips from Microchip use a RISC-V CPU. Since AMD has announced the microblaze-v (their proprietary soft-core CPU with RISC-V ISA), I assume they soon (tm) will release their zynq range with dedicated RISC-V in near future, too. But even if it's an open instruction set, it's still a closed source CPU
picture 2y ago
I'm not sure what you mean. The biggest FPGAs do not have hard processors built in. Those which do feature hard cores usually advertise it specifically. See Xilinx's UltraScale+ Kintex and Virtex series, both able to have more logic elements than the Zynq MP equivalents https://docs.amd.com/v/u/en-US/ds890-ultrascale-overview https://docs.amd.com/v/u/en-US/ds890-ultrascale-overview
- almostgotcaught 2y ago
  yea op (the person you're responding to) is wearing a tinfoil hat. source i work for AMD (formerly xilinx). there are about a billion reasons it isn't true (starting with we'd charge you more money for the IP instead of hiding it) and ending with ultrascales are sold to DoD and there's very little room for shenanigans there.

asddubs 2y ago

What is it for?

dailykoder 2y ago
The ARM Core? It's usually used for anything software you need and the FPGA gets used for any domain specific circuit for signal processing and what not in hardware. The ARM core usually runs a linux or any other OS and is used for communication with other devices. It's just able to run at a higher frequency than most soft-cores, because it's a fully integrated and optimized circuit. So in theory that's a nice thing and gives you more space for custom circuits on the programmable logic part. PS: The latest polarfire chips from Microchip use a RISC-V CPU. Since AMD has announced the microblaze-v (their proprietary soft-core CPU with RISC-V ISA), I assume they soon (tm) will release their zynq range with dedicated RISC-V in near future, too. But even if it's an open instruction set, it's still a closed source CPU

picture 2y ago

I'm not sure what you mean. The biggest FPGAs do not have hard processors built in. Those which do feature hard cores usually advertise it specifically. See Xilinx's UltraScale+ Kintex and Virtex series, both able to have more logic elements than the Zynq MP equivalents https://docs.amd.com/v/u/en-US/ds890-ultrascale-overview https://docs.amd.com/v/u/en-US/ds890-ultrascale-overview

almostgotcaught 2y ago
yea op (the person you're responding to) is wearing a tinfoil hat. source i work for AMD (formerly xilinx). there are about a billion reasons it isn't true (starting with we'd charge you more money for the IP instead of hiding it) and ending with ultrascales are sold to DoD and there's very little room for shenanigans there.