How do I find out which tests from the SBSA suite are run on the system exerciser
All the exerciser tests are available on GitHub. See https://github.com/ARM-software/sbsa-acs/tree/master/test_pool and then select the most recent release tag. The same location will also provide you with all associated PCIe tests.
There is documentation on the exerciser at https://github.com/ARM-software/sbsa-acs/tree/v23.09_REL7.1.3/docs. This location also includes an SBSA testcase checklist which summarises all SBSA rules and indicates those that are covered by the exerciser.
The exerciser tests focus on the PCIe device functionality All tests can be found at https://github.com/ARM-software/sbsa-acs/tree/master/test_pool/pcie