powerpc/powernv/pci: Reserve the root bus PE during init

Doing it once during boot rather than doing it on the fly and drop the janky
populated logic.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200417073508.30356-4-oohall@gmail.com

diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index d9a8703..c4f981c 100644 (file)
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -1145,8 +1145,7 @@ static struct pnv_ioda_pe *pnv_ioda_setup_bus_PE(struct pci_bus *bus, bool all)
        }
 
        /* PE number for root bus should have been reserved */
-       if (pci_is_root_bus(bus) &&
-           phb->ioda.root_pe_idx != IODA_INVALID_PE)
+       if (pci_is_root_bus(bus))
                pe = &phb->ioda.pe_array[phb->ioda.root_pe_idx];
 
        /* Check if PE is determined by M64 */
@@ -3199,15 +3198,6 @@ static void pnv_pci_configure_bus(struct pci_bus *bus)
 
        dev_info(&bus->dev, "Configuring PE for bus\n");
 
-       /* The PE for root bus should be realized before any one else */
-       if (!phb->ioda.root_pe_populated) {
-               pe = pnv_ioda_setup_bus_PE(phb->hose->bus, false);
-               if (pe) {
-                       phb->ioda.root_pe_idx = pe->pe_number;
-                       phb->ioda.root_pe_populated = true;
-               }
-       }
-
        /* Don't assign PE to PCI bus, which doesn't have subordinate devices */
        if (list_empty(&bus->devices))
                return;
@@ -3490,11 +3480,10 @@ static void pnv_ioda_release_pe(struct pnv_ioda_pe *pe)
         * that it can be populated again in PCI hot add path. The PE
         * shouldn't be destroyed as it's the global reserved resource.
         */
-       if (phb->ioda.root_pe_populated &&
-           phb->ioda.root_pe_idx == pe->pe_number)
-               phb->ioda.root_pe_populated = false;
-       else
-               pnv_ioda_free_pe(pe);
+       if (phb->ioda.root_pe_idx == pe->pe_number)
+               return;
+
+       pnv_ioda_free_pe(pe);
 }
 
 static void pnv_pci_release_device(struct pci_dev *pdev)
@@ -3602,6 +3591,7 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
        struct pnv_phb *phb;
        unsigned long size, m64map_off, m32map_off, pemap_off;
        unsigned long iomap_off = 0, dma32map_off = 0;
+       struct pnv_ioda_pe *root_pe;
        struct resource r;
        const __be64 *prop64;
        const __be32 *prop32;
@@ -3769,7 +3759,9 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
                phb->ioda.root_pe_idx = phb->ioda.reserved_pe_idx - 1;
                pnv_ioda_reserve_pe(phb, phb->ioda.root_pe_idx);
        } else {
-               phb->ioda.root_pe_idx = IODA_INVALID_PE;
+               /* otherwise just allocate one */
+               root_pe = pnv_ioda_alloc_pe(phb);
+               phb->ioda.root_pe_idx = root_pe->pe_number;
        }
 
        INIT_LIST_HEAD(&phb->ioda.pe_list);

diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
index 83d40a0..51c254f 100644 (file)
--- a/arch/powerpc/platforms/powernv/pci.h
+++ b/arch/powerpc/platforms/powernv/pci.h
@@ -136,7 +136,6 @@ struct pnv_phb {
                unsigned int            total_pe_num;
                unsigned int            reserved_pe_idx;
                unsigned int            root_pe_idx;
-               bool                    root_pe_populated;
 
                /* 32-bit MMIO window */
                unsigned int            m32_size;