Using PCIe 3.0 on Compute Blade

With the release of CM5, it is now possible to double the speed of the PCIe bus on the Compute Blade when working with the Compute Module from Raspberry Pi. It's quite easy to do, and so far all the tests I've done show high stability of the solution.

Configuration

All you need to do is to add to config.txt at the very end of the file:

dtparam=pciex1
dtparam=pciex1_gen=3

Then reboot the CM5

The CM5 is not certified for PCIe 3.0 not all features may be supported. That is, you should be prepared that in some cases or with some devices it will not work at all or will work with problems. But I haven't had any problems so far because of the PCIe 3.0 activation.

Benchmarks Results

tip

Benchmark by PiBenchmarks can be found on GitHub

Using Compute Blade v1-mk4, Samsung 970 EVO Plus, CM5 4GB module

PCIe	CPU	GPU	Score
2.0 x 1	2.4 GHz	910 MHz	40,799
3.0 x 1	2.4 GHz	910 MHz	56,707
3.0 x 1	3 GHz	910 MHz	60,005
3.0 x 1	3 GHz	1050 MHz	60,215

P.S. What a shame we only have 1x PCIe 3.0 line. In general, there are five of them in the processor. However, if they were brought out on CM5 connectors, all existing carrier boards would be changed. Maybe in CM6 and Compute Blade v.II