v4.19.13 snapshot.
diff --git a/drivers/pci/hotplug/rpaphp_pci.c b/drivers/pci/hotplug/rpaphp_pci.c
new file mode 100644
index 0000000..0aac33e
--- /dev/null
+++ b/drivers/pci/hotplug/rpaphp_pci.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * PCI Hot Plug Controller Driver for RPA-compliant PPC64 platform.
+ * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
+ *
+ * All rights reserved.
+ *
+ * Send feedback to <lxie@us.ibm.com>
+ *
+ */
+#include <linux/pci.h>
+#include <linux/string.h>
+
+#include <asm/pci-bridge.h>
+#include <asm/rtas.h>
+#include <asm/machdep.h>
+
+#include "../pci.h"		/* for pci_add_new_bus */
+#include "rpaphp.h"
+
+int rpaphp_get_sensor_state(struct slot *slot, int *state)
+{
+	int rc;
+	int setlevel;
+
+	rc = rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state);
+
+	if (rc < 0) {
+		if (rc == -EFAULT || rc == -EEXIST) {
+			dbg("%s: slot must be power up to get sensor-state\n",
+			    __func__);
+
+			/* some slots have to be powered up
+			 * before get-sensor will succeed.
+			 */
+			rc = rtas_set_power_level(slot->power_domain, POWER_ON,
+						  &setlevel);
+			if (rc < 0) {
+				dbg("%s: power on slot[%s] failed rc=%d.\n",
+				    __func__, slot->name, rc);
+			} else {
+				rc = rtas_get_sensor(DR_ENTITY_SENSE,
+						     slot->index, state);
+			}
+		} else if (rc == -ENODEV)
+			info("%s: slot is unusable\n", __func__);
+		else
+			err("%s failed to get sensor state\n", __func__);
+	}
+	return rc;
+}
+
+/**
+ * rpaphp_enable_slot - record slot state, config pci device
+ * @slot: target &slot
+ *
+ * Initialize values in the slot, and the hotplug_slot info
+ * structures to indicate if there is a pci card plugged into
+ * the slot. If the slot is not empty, run the pcibios routine
+ * to get pcibios stuff correctly set up.
+ */
+int rpaphp_enable_slot(struct slot *slot)
+{
+	int rc, level, state;
+	struct pci_bus *bus;
+	struct hotplug_slot_info *info = slot->hotplug_slot->info;
+
+	info->adapter_status = NOT_VALID;
+	slot->state = EMPTY;
+
+	/* Find out if the power is turned on for the slot */
+	rc = rtas_get_power_level(slot->power_domain, &level);
+	if (rc)
+		return rc;
+	info->power_status = level;
+
+	/* Figure out if there is an adapter in the slot */
+	rc = rpaphp_get_sensor_state(slot, &state);
+	if (rc)
+		return rc;
+
+	bus = pci_find_bus_by_node(slot->dn);
+	if (!bus) {
+		err("%s: no pci_bus for dn %pOF\n", __func__, slot->dn);
+		return -EINVAL;
+	}
+
+	info->adapter_status = EMPTY;
+	slot->bus = bus;
+	slot->pci_devs = &bus->devices;
+
+	/* if there's an adapter in the slot, go add the pci devices */
+	if (state == PRESENT) {
+		info->adapter_status = NOT_CONFIGURED;
+		slot->state = NOT_CONFIGURED;
+
+		/* non-empty slot has to have child */
+		if (!slot->dn->child) {
+			err("%s: slot[%s]'s device_node doesn't have child for adapter\n",
+			    __func__, slot->name);
+			return -EINVAL;
+		}
+
+		if (list_empty(&bus->devices))
+			pci_hp_add_devices(bus);
+
+		if (!list_empty(&bus->devices)) {
+			info->adapter_status = CONFIGURED;
+			slot->state = CONFIGURED;
+		}
+
+		if (rpaphp_debug) {
+			struct pci_dev *dev;
+			dbg("%s: pci_devs of slot[%pOF]\n", __func__, slot->dn);
+			list_for_each_entry(dev, &bus->devices, bus_list)
+				dbg("\t%s\n", pci_name(dev));
+		}
+	}
+
+	return 0;
+}