Small bugs at axi_slave.py

[spoursalidis]

Hello,

I initialise an AxiRam with:
mem = AxiRam(AxiBus.from_prefix(dut, 'm_axi'), dut.clk, size=RAM_SIZE)

In the "axi_slave.py" file at lines 114 & 274, the awid and arid signals cannot be resolved:

• ValueError: Unresolvable bit in binary string: 'U'

I have fixed that by setting at the beginning of my testbench "dut.m_axi_arid.value = 0" and "dut.m_axi_awid.value = 0". I thought it would be done automatically during the initialisation of the AxiRam.

Also at lines 119 & 279 I had to add an int() to make it work:

line 119: prot = AxiProt(int(getattr(aw, 'awprot', AxiProt.NONSECURE)))
line 279: prot = AxiProt(int(getattr(ar, 'arprot', AxiProt.NONSECURE)))