On Wed, May 07, 2025 at 01:34:37AM +0800, Hans Zhang wrote:
(snip)
> static void pci_configure_mps(struct pci_dev *dev)
> {
> struct pci_dev *bridge = pci_upstream_bridge(dev);
> @@ -2178,6 +2209,10 @@ static void pci_configure_mps(struct pci_dev *dev)
> return;
> }
We should probably add a comment explaining why we are doing this here.
Perhaps something like:
/*
* Unless MPS strategy is PCIE_BUS_TUNE_OFF (don't touch MPS at all),
* start off by setting root ports' MPS to MPSS. Depending on the MPS
* strategy, and the MPSS of the devices below the root port, the MPS
* of the root port might get overriden later.
*/
> + if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT &&
> + pcie_bus_config != PCIE_BUS_TUNE_OFF)
> + pcie_write_mps(dev, 128 << dev->pcie_mpss);
> +
> if (!bridge || !pci_is_pcie(bridge))
> return;
>
Kind regards,
Niklas
