Root Complex Integrated Endpoint devices (PCI_EXP_TYPE_RC_END) are
directly integrated into the root complex and do not have an
associated Root Port in the traditional PCIe hierarchy. The current
TPH implementation incorrectly attempts to find and check a Root Port's
TPH completer capability for these devices.
Add a check to skip Root Port completer type verification for RC_END
devices, allowing them to use their full TPH requester capability
without being limited by a non-existent Root Port's completer support.
For RC_END devices, the root complex itself acts as the TPH completer,
and this relationship is handled differently than the standard
endpoint-to-Root-Port model.
Fixes: f69767a1ada3 ("PCI: Add TLP Processing Hints (TPH) support")
Signed-off-by: George Abraham P <george.abraham.p@intel.com>
---
v1->v2:
- Added "Fixes:" tag to link the commit hash that introduced the code
---
drivers/pci/tph.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/pci/tph.c b/drivers/pci/tph.c
index ca4f97be7538..e896b3958281 100644
--- a/drivers/pci/tph.c
+++ b/drivers/pci/tph.c
@@ -407,10 +407,13 @@ int pcie_enable_tph(struct pci_dev *pdev, int mode)
else
pdev->tph_req_type = PCI_TPH_REQ_TPH_ONLY;
- rp_req_type = get_rp_completer_type(pdev);
+ /* Check if the device is behind a Root Port */
+ if (pci_pcie_type(pdev) != PCI_EXP_TYPE_RC_END) {
+ rp_req_type = get_rp_completer_type(pdev);
- /* Final req_type is the smallest value of two */
- pdev->tph_req_type = min(pdev->tph_req_type, rp_req_type);
+ /* Final req_type is the smallest value of two */
+ pdev->tph_req_type = min(pdev->tph_req_type, rp_req_type);
+ }
if (pdev->tph_req_type == PCI_TPH_REQ_DISABLE)
return -EINVAL;
--
2.40.1