powerpc/powernv: Functions to get/set PCI slot state

This exports 4 functions, which base on the corresponding OPAL
APIs to get/set PCI slot status. Those functions are going to
be used by PowerNV PCI hotplug driver:

   pnv_pci_get_device_tree()    opal_get_device_tree()
   pnv_pci_get_presence_state() opal_pci_get_presence_state()
   pnv_pci_get_power_state()    opal_pci_get_power_state()
   pnv_pci_set_power_state()    opal_pci_set_power_state()

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/include/asm/pnv-pci.h b/arch/powerpc/include/asm/pnv-pci.h
index 810cc9a..791db1b 100644
--- a/arch/powerpc/include/asm/pnv-pci.h
+++ b/arch/powerpc/include/asm/pnv-pci.h
@@ -12,12 +12,18 @@
 
 #include <linux/pci.h>
 #include <misc/cxl-base.h>
+#include <asm/opal-api.h>
 
 #define PCI_SLOT_ID_PREFIX	0x8000000000000000
 #define PCI_SLOT_ID(phb_id, bdfn)	\
 	(PCI_SLOT_ID_PREFIX | ((uint64_t)(bdfn) << 16) | (phb_id))
 
 extern int pnv_pci_get_slot_id(struct device_node *np, uint64_t *id);
+extern int pnv_pci_get_device_tree(uint32_t phandle, void *buf, uint64_t len);
+extern int pnv_pci_get_presence_state(uint64_t id, uint8_t *state);
+extern int pnv_pci_get_power_state(uint64_t id, uint8_t *state);
+extern int pnv_pci_set_power_state(uint64_t id, uint8_t state,
+				   struct opal_msg *msg);
 
 int pnv_phb_to_cxl_mode(struct pci_dev *dev, uint64_t mode);
 int pnv_cxl_ioda_msi_setup(struct pci_dev *dev, unsigned int hwirq,