powerpc/pci: Add shutdown hook to pci_controller_ops

Currently pnv_pci_shutdown() calls the PHB shutdown code for all PHBs in the
system.  It dereferences the private_data assuming it's a powernv PHB, which
won't be the case when we have different PHB in the systems (like when we add
vPHBs for CXL).

This moves the shutdown hook to the pci_controller_ops and fixes the call site
to use that instead.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/pci-bridge.h

@@ -40,6 +40,8 @@ struct pci_controller_ops {
 #endif
 
 	int             (*dma_set_mask)(struct pci_dev *dev, u64 dma_mask);
+
+	void		(*shutdown)(struct pci_controller *);
 };
 
 /*

arch/powerpc/platforms/powernv/pci-ioda.c

@@ -2643,8 +2643,10 @@ static u32 pnv_ioda_bdfn_to_pe(struct pnv_phb *phb, struct pci_bus *bus,
 	return phb->ioda.pe_rmap[(bus->number << 8) | devfn];
 }
 
-static void pnv_pci_ioda_shutdown(struct pnv_phb *phb)
+static void pnv_pci_ioda_shutdown(struct pci_controller *hose)
 {
+	struct pnv_phb *phb = hose->private_data;
+
 	opal_pci_reset(phb->opal_id, OPAL_RESET_PCI_IODA_TABLE,
 		       OPAL_ASSERT_RESET);
 }
@@ -2659,6 +2661,7 @@ static const struct pci_controller_ops pnv_pci_ioda_controller_ops = {
        .window_alignment = pnv_pci_window_alignment,
        .reset_secondary_bus = pnv_pci_reset_secondary_bus,
        .dma_set_mask = pnv_pci_ioda_dma_set_mask,
+       .shutdown = pnv_pci_ioda_shutdown,
 };
 
 static void __init pnv_pci_init_ioda_phb(struct device_node *np,
@@ -2806,9 +2809,6 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
 	phb->dma_dev_setup = pnv_pci_ioda_dma_dev_setup;
 	phb->dma_get_required_mask = pnv_pci_ioda_dma_get_required_mask;
 
-	/* Setup shutdown function for kexec */
-	phb->shutdown = pnv_pci_ioda_shutdown;
-
 	/* Setup MSI support */
 	pnv_pci_init_ioda_msis(phb);
 

arch/powerpc/platforms/powernv/pci.c

@@ -704,12 +704,9 @@ void pnv_pci_shutdown(void)
 {
 	struct pci_controller *hose;
 
-	list_for_each_entry(hose, &hose_list, list_node) {
-		struct pnv_phb *phb = hose->private_data;
-
-		if (phb && phb->shutdown)
-			phb->shutdown(phb);
-	}
+	list_for_each_entry(hose, &hose_list, list_node)
+		if (hose->controller_ops.shutdown)
+			hose->controller_ops.shutdown(hose);
 }
 
 /* Fixup wrong class code in p7ioc and p8 root complex */

arch/powerpc/platforms/powernv/pci.h

@@ -110,7 +110,6 @@ struct pnv_phb {
 				     struct pci_dev *pdev);
 	void (*fixup_phb)(struct pci_controller *hose);
 	u32 (*bdfn_to_pe)(struct pnv_phb *phb, struct pci_bus *bus, u32 devfn);
-	void (*shutdown)(struct pnv_phb *phb);
 	int (*init_m64)(struct pnv_phb *phb);
 	void (*reserve_m64_pe)(struct pnv_phb *phb);
 	int (*pick_m64_pe)(struct pnv_phb *phb, struct pci_bus *bus, int all);