Re: [PATCH v3 1/3] PCI: Configure root port MPS during host probing
From: Niklas Cassel <cassel@kernel.org>
Date: 2025-05-07 07:38:09
Also in:
linux-amlogic, linux-pci, linux-rockchip, lkml
On Wed, May 07, 2025 at 01:34:37AM +0800, Hans Zhang wrote: (snip)
quoted hunk ↗ jump to hunk
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