pci_ep: Add the init function

Some EP deivces need to initialize before RC scan it, e.g. NXP
layerscape platform, so add the init function in pci_ep uclass.

Signed-off-by: Xiaowei Bao <xiaowei.bao@nxp.com>
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/common/board_r.c b/common/board_r.c
index 67dc25c..d9307f0 100644
--- a/common/board_r.c
+++ b/common/board_r.c
@@ -233,6 +233,15 @@
 }
 #endif
 
+#ifdef CONFIG_PCI_ENDPOINT
+static int initr_pci_ep(void)
+{
+	pci_ep_init();
+
+	return 0;
+}
+#endif
+
 #ifdef CONFIG_PCI
 static int initr_pci(void)
 {
@@ -816,6 +825,9 @@
 #ifdef CONFIG_BITBANGMII
 	initr_bbmii,
 #endif
+#ifdef CONFIG_PCI_ENDPOINT
+	initr_pci_ep,
+#endif
 #ifdef CONFIG_CMD_NET
 	INIT_FUNC_WATCHDOG_RESET
 	initr_net,
diff --git a/drivers/pci_endpoint/pci_ep-uclass.c b/drivers/pci_endpoint/pci_ep-uclass.c
index 9f53a9a..38a5f08 100644
--- a/drivers/pci_endpoint/pci_ep-uclass.c
+++ b/drivers/pci_endpoint/pci_ep-uclass.c
@@ -209,3 +209,14 @@
 	.name		= "pci_ep",
 	.flags		= DM_UC_FLAG_SEQ_ALIAS,
 };
+
+void pci_ep_init(void)
+{
+	struct udevice *dev;
+
+	for (uclass_first_device_check(UCLASS_PCI_EP, &dev);
+	     dev;
+	     uclass_next_device_check(&dev)) {
+		;
+	}
+}
diff --git a/include/init.h b/include/init.h
index e727031..de408ba 100644
--- a/include/init.h
+++ b/include/init.h
@@ -213,6 +213,7 @@
 int update_flash_size(int flash_size);
 int arch_early_init_r(void);
 void pci_init(void);
+void pci_ep_init(void);
 int misc_init_r(void);
 #if defined(CONFIG_VID)
 int init_func_vid(void);