[PATCH 5/8] PCI: endpoint: Add BME notifier support

From: Manivannan Sadhasivam
Date: Mon May 02 2022 - 02:07:24 EST


Add support to notify the EPF device about the Bus Master Enable (BME)
event received by the EPC device from the Root complex.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/pci/endpoint/pci-epc-core.c | 17 +++++++++++++++++
include/linux/pci-epc.h | 1 +
include/linux/pci-epf.h | 1 +
3 files changed, 19 insertions(+)

diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index 8401c2750c9e..6120d99bff73 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -731,6 +731,23 @@ void pci_epc_init_notify(struct pci_epc *epc)
}
EXPORT_SYMBOL_GPL(pci_epc_init_notify);

+/**
+ * pci_epc_bme_notify() - Notify the EPF device that the EPC device has received
+ * the BME event from the Root complex
+ * @epc: the EPC device that received the BME event
+ *
+ * Invoke to Notify the EPF device that the EPC device has received the Bus
+ * Master Enable (BME) event from the Root complex
+ */
+void pci_epc_bme_notify(struct pci_epc *epc)
+{
+ if (!epc || IS_ERR(epc))
+ return;
+
+ atomic_notifier_call_chain(&epc->notifier, BME, NULL);
+}
+EXPORT_SYMBOL_GPL(pci_epc_bme_notify);
+
/**
* pci_epc_destroy() - destroy the EPC device
* @epc: the EPC device that has to be destroyed
diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
index d346ab9ae061..8454610df4c3 100644
--- a/include/linux/pci-epc.h
+++ b/include/linux/pci-epc.h
@@ -217,6 +217,7 @@ int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf,
void pci_epc_linkup(struct pci_epc *epc);
void pci_epc_linkdown(struct pci_epc *epc);
void pci_epc_init_notify(struct pci_epc *epc);
+void pci_epc_bme_notify(struct pci_epc *epc);
void pci_epc_remove_epf(struct pci_epc *epc, struct pci_epf *epf,
enum pci_epc_interface_type type);
int pci_epc_write_header(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h
index b1fcd88d0b1f..e03c57129ed5 100644
--- a/include/linux/pci-epf.h
+++ b/include/linux/pci-epf.h
@@ -21,6 +21,7 @@ enum pci_notify_event {
CORE_INIT,
LINK_UP,
LINK_DOWN,
+ BME,
};

enum pci_barno {
--
2.25.1