[PATCH v2 4/7] PCI: endpoint: Add BME notifier support

From: Manivannan Sadhasivam
Date: Tue Mar 07 2023 - 10:18:07 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 | 26 ++++++++++++++++++++++++++
include/linux/pci-epc.h | 1 +
include/linux/pci-epf.h | 2 ++
3 files changed, 29 insertions(+)

diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index e3a6b5554c1c..11bd873a7997 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -758,6 +758,32 @@ 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)
+{
+ struct pci_epf *epf;
+
+ if (!epc || IS_ERR(epc))
+ return;
+
+ mutex_lock(&epc->list_lock);
+ list_for_each_entry(epf, &epc->pci_epf, list) {
+ mutex_lock(&epf->lock);
+ if (epf->event_ops && epf->event_ops->bme)
+ epf->event_ops->bme(epf);
+ mutex_unlock(&epf->lock);
+ }
+ mutex_unlock(&epc->list_lock);
+}
+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 63a6cc5e5282..5cb694031072 100644
--- a/include/linux/pci-epc.h
+++ b/include/linux/pci-epc.h
@@ -205,6 +205,7 @@ 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 f8e5a63d0c83..f34b3b32a0e7 100644
--- a/include/linux/pci-epf.h
+++ b/include/linux/pci-epf.h
@@ -72,11 +72,13 @@ struct pci_epf_ops {
* @core_init: Callback for the EPC initialization complete event
* @link_up: Callback for the EPC link up event
* @link_down: Callback for the EPC link down event
+ * @bme: Callback for the EPC BME (Bus Master Enable) event
*/
struct pci_epc_event_ops {
int (*core_init)(struct pci_epf *epf);
int (*link_up)(struct pci_epf *epf);
int (*link_down)(struct pci_epf *epf);
+ int (*bme)(struct pci_epf *epf);
};

/**
--
2.25.1