[PATCH 08/18] PCI/TSM: Support connecting to PCIe CMA devices

[alistair23]

From: Alistair Francis <alistair.francis@xxxxxxx>

In the next patch we are going to add a PCIe CMA TSM driver, as such we
need to ensure that is_pci_tsm_pf0() will allow us to connect to CMA
capable devices. These devices don't necessarily has DEVCAP_TEE or IDE
support.

As such for Root Complex Integrated Endpoint (PCI_EXP_TYPE_RC_END) we
also check for the CMA DOE feature.

Signed-off-by: Alistair Francis <alistair.francis@xxxxxxx>
---
 include/linux/pci-tsm.h | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/include/linux/pci-tsm.h b/include/linux/pci-tsm.h
index a6435aba03f9..5059954e4853 100644
--- a/include/linux/pci-tsm.h
+++ b/include/linux/pci-tsm.h
@@ -3,6 +3,7 @@
 #define __PCI_TSM_H
 #include <linux/mutex.h>
 #include <linux/pci.h>
+#include <linux/pci-doe.h>
 #include <linux/sockptr.h>
 
 struct pci_tsm;
@@ -129,6 +130,8 @@ struct pci_tsm_pf0 {
 /* physical function0 and capable of 'connect' */
 static inline bool is_pci_tsm_pf0(struct pci_dev *pdev)
 {
+	struct pci_doe_mb *doe;
+
 	if (!pdev)
 		return false;
 
@@ -146,9 +149,15 @@ static inline bool is_pci_tsm_pf0(struct pci_dev *pdev)
 	 * switch.
 	 */
 	switch (pci_pcie_type(pdev)) {
+	case PCI_EXP_TYPE_RC_END:
+		doe = pci_find_doe_mailbox(pdev, PCI_VENDOR_ID_PCI_SIG,
+					   PCI_DOE_FEATURE_CMA);
+
+		if (doe)
+			break;
+		fallthrough;
 	case PCI_EXP_TYPE_ENDPOINT:
 	case PCI_EXP_TYPE_UPSTREAM:
-	case PCI_EXP_TYPE_RC_END:
 		if (pdev->ide_cap || (pdev->devcap & PCI_EXP_DEVCAP_TEE))
 			break;
 		fallthrough;
-- 
2.52.0