WARNING: This is not a full project but just a short hack to disable the fan.
By cloning the Vitis platforms repository and building the first platform for Vivado I learned that the actual fan is driven from pin A12 on the package of the actual device used on the SOM that is used on the KV260.
For this first project I simply switch off the fan by tying the control signal to a logic '1'. Next steps of course will include a nice temperature controlled fan controller but first I want the annoying sound to stop without pulling the wire.
The connect the two components by drawing a wire from the Constant to the port.
The next step is to create a HDL wrapper for the Block Design.
By right clicking the.bd file in the Design Sources tree you can select 'Create HDL Wrapper' and click through to simply use the default selections.
In the RTL Analysis section you can create a schematic and this is one of the many points were you can assign the right package pin to the created output port.
Assign the port to package pin A12 and select LVCMOS33 as I/O Standard.
Now you are ready to fully compile the project and generate the bitstream to configure the PL portion of the Zynq UltraScale+ device on the Kria SOM.
Simply click 'Generate Bitstream' from the Program and Debug section of the Flow Navigator and Vivado should perform all steps necessary to get to that point. The involves all kinds of design rule checking, synthesis and the actual implementation. I will not go in details here but you can learn about that at https://www.xilinx.com/support/documentation-navigation/design-hubs/dh0002-vivado-design-flows-overview-hub.html
After connection the board using a microUSB cable and connector J4 to your PC you should be able to connect to the device and reprogram the xck26_0 device using the bitstream. This will destroy the accelerated app running on the PL section but the fan will stop running and using the SysMon of the Hardware Manager you can watch the temperature of the device start to climb. Mine settled at 54 deg C and that should be fine for a device doing noting but reporting the die temperature using the JTAG interface. Of course this in not usable in actual project and you should always implement a control scheme for the fan to start as soon as the temperature starts to rise above the desired values (or is getting near the maximum temperature specified in the datasheet).
Like stated in the warning above, this is just a quick and dirty hack and you can use the knowledge gained to start a proper thermal control loop design for the KV260.
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