Xilinx XCZU2EG - Flashing spi flash over jtag?

[glenneaux]

Have this device



Want to play around with flashing the spi flash, and can do from uboot.

But if something goes wrong, it will be one way flash.

Can I flash this memory via jtag without the sources ? What's required software/hardware wise? Can we get away with an stlink converted into jlink?

[laugensalm]

I haven't tried on this particular platform, but you should be able to access a standard boot flash via OpenOCD and any supported third party adapter, there are various config files for MPSoC platforms.
There are two methods, one is the CPU built-in in circuit emulation which works for standard boot flashes, typically. The hard low level method is boundary scan which allows you to selectively toggle pins, but you need a config file and be very much aware of which pins you are toggling, meaning, there is no general solution and you might have to dig into the BSCAN tools.
WRT original JLink, I remember issues with different firmware versions in openOCD, but in general it should work.

[asmi]

Vivado Hardware Manager allows you to read/write boot qspi flash via JTAG. So you can use it to back up existing programming as well as to program something new.

[glenneaux]

Vivado Hardware Manager allows you to read/write boot qspi flash via JTAG. So you can use it to back up existing programming as well as to program something new.

That sounds promising. Is there a cheap tool that will work? Would a knock off platform cable do the trick?

[asmi]

That sounds promising. Is there a cheap tool that will work? Would a knock off platform cable do the trick?

Don't know about knock-offs, but you can buy a "legal" JTAG-HS3 cable from Digilent for $59, or build the one yourself for about $10 worth of parts and program it using a tool provided by AMD/Xilinx to turn it into a "real" debugger.