Hi Bjorn and Lorenzo,
Any comments on this change?
-----Original Message-----
From: Z.Q. Hou <zhiqiang.hou@xxxxxxx>
Sent: 2022年6月10日 23:02
To: linux-pci@xxxxxxxxxxxxxxx; bhelgaas@xxxxxxxxxx
Cc: Z.Q. Hou <zhiqiang.hou@xxxxxxx>
Subject: [PATCH] PCI: Align MPS to upstream bridge for SAFE and PERFORMANCE mode
From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
The commit 27d868b5e6cf ("PCI: Set MPS to match upstream bridge") made the device's MPS matches upstream bridge for PCIE_BUS_DEFAULT mode, so that it's more likely that a hot-added device will work in a system with an optimized MPS configuration.
Obviously, the Linux itself optimizes the MPS settings in the PCIE_BUS_SAFE and PCIE_BUS_PERFORMANCE mode, so let's do this also for these modes.
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
---
drivers/pci/probe.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 17a969942d37..2c5a1aefd9cb 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -2034,7 +2034,9 @@ static void pci_configure_mps(struct pci_dev *dev)
* Fancier MPS configuration is done later by
* pcie_bus_configure_settings()
*/
- if (pcie_bus_config != PCIE_BUS_DEFAULT)
+ if (pcie_bus_config != PCIE_BUS_DEFAULT &&
+ pcie_bus_config != PCIE_BUS_SAFE &&
+ pcie_bus_config != PCIE_BUS_PERFORMANCE)
return;
mpss = 128 << dev->pcie_mpss;
@@ -2047,7 +2049,7 @@ static void pci_configure_mps(struct pci_dev *dev)
rc = pcie_set_mps(dev, p_mps);
if (rc) {
- pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
+ pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use
+\"pci=pcie_bus_peer2peer\" and report a bug\n",
p_mps);
return;
}
--
2.17.1
Thanks,
Zhiqiang
