Rework testbench logging

tests/gmii/test_gmii.py

@@ -24,12 +24,14 @@ THE SOFTWARE.
 """
 
 import itertools
+import logging
 import os
 
 import cocotb_test.simulator
 import pytest
 
 import cocotb
+from cocotb.log import SimLog
 from cocotb.clock import Clock
 from cocotb.triggers import RisingEdge
 from cocotb.regression import TestFactory
@@ -40,6 +42,9 @@ class TB(object):
     def __init__(self, dut):
         self.dut = dut
 
+        self.log = SimLog(f"cocotb.tb")
+        self.log.setLevel(logging.DEBUG)
+
         cocotb.fork(Clock(dut.clk, 2, units="ns").start())
 
         self.source = GmiiSource(dut, "gmii", dut.clk, dut.rst)