7 Series FPGAs

[maxthemagnificent]

Re a recent blog on All Programmable Planet -- The Future of FPGAs/MCUs – What Are Today's Challenges? -- member "rfindley" commented:

"One thing that surprised me about the FPGA side, though, is that in the Zynq, the FPGA fabric no longer has the means to self-program... it must be programmed by the MCU core.  I suppose that model makes sense, knowing that it is truly a MCU-centric device, not just an FPGA with a supporting processor."

Is this true? Does this mean that you can no longer program the FPGA fabric automatically on power-up from an external FLASH chip? If so, what about partial reconfiguration of the programmable fabric -- does this have to be performed under MCU control also?

[austin]

Max,

Half-true...mostly false.

The intitial configuraton of the programmable logic is managed (now) by the ARM programmable processors side.  This allows the security features of hte ARM system to be the master, and provides a better and more usable device.

Looks like a uC, acts like a uC.

Once configured, one may have placed the ICAP in your design, so now the programmable logic has the ability to configure again, reconfigure, etc. (nothing is lost whatsoever over the rest of the 7-series family parts).

I would, however, be careful, as if you do have the security enabled (decryption, etc.) having an ICAP is a perfect 'back-door' for those who are attacking the design (if it is used in a way that allows access).

The ICAP does get used for the soft error mitigation IP core, so that is one use that is not providing such a 'back-door' yet makes full use of the reconfigurability of the programmable logic side if the Zynq device.