Build and Test packet redirection example

[JosueOrtiz-fpga]

Look into Vitis SDT

[JosueOrtiz-fpga]

Resolved build errors by providing valid BASE_ADDR arguments to CFG functions which were previously being passed ID MACROs that are deprecated with the new SDT feature of Vitis 2024.

Project builds and application runs reporting all passing but visually inspecting the PL Rx Buffer contents shows that it is empty!

• Print statements were inserted to verify that TxBuffer was not all 0s as well.
• For reading the RxBuffer values, Xil_In32 calls were inserted but these report 0s for the first 64 returns.

Current thoughts on next steps:

1. Using an JTAG-AXI core, the BRAM contents can be read independently to see if RxBuffer gets filled or not which can isolate the issue.
2. Evaluate ScuGicSelfTestExample and ScuGicInterruptSetup procedures in testperiph.c to ensure those are not producing false positives

[JosueOrtiz-fpga]

Thoughts after reading the Reference Manual GEM and GIC sections:

• The MAC will only push packets to the receive buffers for DMA if the address matches what's setup in the registers
• This can be turned off by setting the COPY_ALL_EN bit 4 of the XEMACPS_NWCFG_OFFSET register
• When the MAC consumes a RX Buffer Descriptor (BD) it sets Word 0 bit 0 indicating it is used: this can be polled by software to determine how many BDs have bee used. Software must unset the bit to allow the MAC to use the BD again.
• The MAC will write a status output the RX BD Word 1 for status, this can also be read by software.
• I believe there are similar bits that can be read to get information on the TX side of things.
• There's a cool Wake-on-Lan interrupt supported: maybe this can be used to read the GIC registers and GEM intr registers to look for correct functionality.
• There is a system addresses table in the tech guide which we can refer to and see where memory is being implemented.
• The tech guide provides a guide for setting up the MAC via registers; maybe these same registers can be read as test after the CFG/INIT functions to see if it matches what's configured by the IP block.
• The registers can also be used to directly control the MAC and not use the driver