Vivado Critial Warnings
Vivado generates some Critical Warnings during synthesis and implementation (spec7_ref_design/spec7_wr_ref_top.vhd):
Synth 8-6030 is due to the fact that pin "fmc_la01_cc_p" is (properly) defined as an "inout" in the top VHDL file while the pins is only used as output. This is also the case for pin "fmc_la30_p" (see figure below) although there is no warning about this pin.
The fact that "fmc_la01_cc_p" generates a warning is due to the fact that the input signal that drives "fmc_la01_cc_p", also drives "led_pps_o":
led_pps_o <= pps_led_ext;
fmc_la01_cc_p <= pps_led_ext; -- dio_led_top_o
Without driving "led_pps_o":
led_pps_o <= '0';
fmc_la01_cc_p <= pps_led_ext; -- dio_led_top_o
there is no Critical Warning.
After all, as can be seen in the figure above, the Critical Warning can be omitted since the final implementation is correct.
Memdata 28-127 is due to the fact that a Block Memory Mapping (BMM) file (for the LM32 memory mapping) is added to the project. For Vivado, any BMM file is connected to a Xilinx soft-core processor. Vivado stubbornly refuses to accept that third party processors (like LM32) also need their BMM files to be added. This Critical Warning can be omitted.