A PASID-like feature is implemented on AMBA without using TLP prefixes
and these devices have PASID capability though not supporting TLP.
Adding a pasid_no_tlp bit for "PASID works without TLP prefixes" and
pci_enable_pasid() checks pasid_no_tlp as well as eetlp_prefix_path.
Suggested-by: Bjorn Helgaas <helgaas@xxxxxxxxxx>
Signed-off-by: Zhangfei Gao <zhangfei.gao@xxxxxxxxxx>
---
drivers/pci/ats.c | 2 +-
include/linux/pci.h | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index 6d7d649..c967ad6 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -376,7 +376,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
if (WARN_ON(pdev->pasid_enabled))
return -EBUSY;
- if (!pdev->eetlp_prefix_path)
+ if (!pdev->eetlp_prefix_path && !pdev->pasid_no_tlp)
return -EINVAL;
if (!pasid)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index c20211e..766dca1 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -388,6 +388,7 @@ struct pci_dev {
supported from root to here */
u16 l1ss; /* L1SS Capability pointer */
#endif
+ unsigned int pasid_no_tlp:1; /* PASID works without TLP Prefix */
unsigned int eetlp_prefix_path:1; /* End-to-End TLP Prefix */
pci_channel_state_t error_state; /* Current connectivity state */
--
2.7.4
