Rocket chip not reading instructions

**Type of issue**: bug report

**Impact**: unknown

**Development Phase**: request

**If the current behavior is a bug, please provide the steps to reproduce the problem:**

connect the rocket chip to memory using AXI and observe the AXI signals after removing the reset. on real HW.

the configuration used was "ZynqFPGAConfig" found at: https://github.com/ucb-bar/fpga-zynq

**What is the current behavior?**

the rocket chip should read instructions from memory.

**What is the expected behavior?**

the rocket chip seems to do nothing. the ILA (Integrated Logic Analyzer) provided by vivado does indicate that the AXI interface is Inactive and that no read commands are executed.

Begin by reproducing the issue with the ZynqFPGAConfig configuration from fpga-zynq, connecting the Rocket chip to memory over AXI on real hardware. Observe the AXI signals with Vivado ILA after reset is removed; done means determining why no read commands occur and documenting or resolving the cause.

Written by the indexing model from the issue text.