I have written about this in the gem5-aladdin group some time ago but configs/aladdin/aladdin_se.py needs some further configuration to set the CPU clock correctly or CPU will be set at system clock.

You need to add:

# All cpus belong to a common cpu_clk_domain, therefore running at a common     
# frequency.                                                           
for cpu in system.cpu:    
    cpu.clk_domain = system.cpu_clk_domain

I have put it at line 333 since gem5 puts it there, but I think is fine anywhere.