cxl: Fix retrieving of access_coordinates in PCIe path

Current loop in cxl_endpoint_get_perf_coordinates() incorrectly assumes
the Root Port (RP) dport is the one with generic port access_coordinate.
However those coordinates are one level up in the Host Bridge (HB).
Current code causes the computation code to pick up 0s as the coordinates
and cause minimal bandwidth to result in 0.

Add check to skip RP when combining coordinates.

Fixes: 14a6960b3e ("cxl: Add helper function that calculate performance data for downstream ports")
Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/20240403154844.3403859-3-dave.jiang@intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
This commit is contained in:
Dave Jiang 2024-04-03 08:47:13 -07:00
commit 592780b839