Speed! when reading from the serial port

Hello again,

I am trying to increase the data and instruction cache to test if the speed increases when reading data from the UART. At first, I tried making it four times bigger, Quartus said it couldn't fit into the device, so I eliminated the VGA and Audio modules in SOPC (I am not using them). After that I increased Instruction Cache to 8 KBytes, and Data Cache to 4 KBytes, which is the double of what I had by default.

Quartus compiles the project succesfully, and everything is loaded into the FPGA. However, when I open nios2-terminal it never boots correctly, It just freezes after "Uncompressing........done" And then nothing happens. I don't know if I should change something in the kernel or app config. Because I've tried so far with different combinations of Data and Instruction Cache sizes, but none of them boots correctly, except for the default values (4 K Instruction and 2K data).

Any ideas on this please? :S

Regards,

Francisco