From 98611dd735b472c23cc1e8cca90a997393a3a955 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Mon, 31 Jul 2017 17:37:54 +0100 Subject: [PATCH] tile/PCI: Replace pci_fixup_irqs() call with host bridge IRQ mapping hooks The pci_fixup_irqs() function allocates IRQs for all PCI devices present in a system; those PCI devices possibly belong to different PCI bus trees (and possibly rooted at different host bridges) and may well be enabled (ie probed and bound to a driver) by the time pci_fixup_irqs() is called when probing a given host bridge driver. Furthermore, current kernel code relying on pci_fixup_irqs() to assign legacy PCI IRQs to devices does not work at all for hotplugged devices in that the code carrying out the IRQ fixup is called at host bridge driver probe time, which just cannot take into account devices hotplugged after the system has booted. The introduction of map/swizzle function hooks in struct pci_host_bridge allows us to define per-bridge map/swizzle functions that can be used at device probe time in PCI core code to allocate IRQs for a given device (through pci_assign_irq()). Convert PCI host bridge initialization code to the pci_scan_root_bus_bridge() API (that allows to pass a struct pci_host_bridge with initializedmap/swizzle pointers) and remove the pci_fixup_irqs() call from arch code. Signed-off-by: Lorenzo Pieralisi Signed-off-by: Bjorn Helgaas Cc: Chris Metcalf --- arch/tile/kernel/pci.c | 21 ++++++++++++++++----- arch/tile/kernel/pci_gx.c | 21 ++++++++++++++++----- 2 files changed, 32 insertions(+), 10 deletions(-) diff --git a/arch/tile/kernel/pci.c b/arch/tile/kernel/pci.c index bc6656b5708b..884826157765 100644 --- a/arch/tile/kernel/pci.c +++ b/arch/tile/kernel/pci.c @@ -274,6 +274,7 @@ static void fixup_read_and_payload_sizes(void) */ int __init pcibios_init(void) { + struct pci_host_bridge *bridge; int i; pr_info("PCI: Probing PCI hardware\n"); @@ -306,16 +307,26 @@ int __init pcibios_init(void) pci_add_resource(&resources, &ioport_resource); pci_add_resource(&resources, &iomem_resource); - bus = pci_scan_root_bus(NULL, 0, controller->ops, - controller, &resources); + + bridge = pci_alloc_host_bridge(0); + if (!bridge) + break; + + list_splice_init(&resources, &bridge->windows); + bridge->dev.parent = NULL; + bridge->sysdata = controller; + bridge->busnr = 0; + bridge->ops = controller->ops; + bridge->swizzle_irq = pci_common_swizzle; + bridge->map_irq = tile_map_irq; + + pci_scan_root_bus_bridge(bridge); + bus = bridge->bus; controller->root_bus = bus; controller->last_busno = bus->busn_res.end; } } - /* Do machine dependent PCI interrupt routing */ - pci_fixup_irqs(pci_common_swizzle, tile_map_irq); - /* * This comes from the generic Linux PCI driver. * diff --git a/arch/tile/kernel/pci_gx.c b/arch/tile/kernel/pci_gx.c index b554a68eea1b..e68317083ac7 100644 --- a/arch/tile/kernel/pci_gx.c +++ b/arch/tile/kernel/pci_gx.c @@ -669,6 +669,7 @@ int __init pcibios_init(void) resource_size_t offset; LIST_HEAD(resources); int next_busno; + struct pci_host_bridge *bridge; int i; tile_pci_init(); @@ -881,15 +882,25 @@ int __init pcibios_init(void) controller->mem_offset); pci_add_resource(&resources, &controller->io_space); controller->first_busno = next_busno; - bus = pci_scan_root_bus(NULL, next_busno, controller->ops, - controller, &resources); + + bridge = pci_alloc_host_bridge(0); + if (!bridge) + break; + + list_splice_init(&resources, &bridge->windows); + bridge->dev.parent = NULL; + bridge->sysdata = controller; + bridge->busnr = next_busno; + bridge->ops = controller->ops; + bridge->swizzle_irq = pci_common_swizzle; + bridge->map_irq = tile_map_irq; + + pci_scan_root_bus_bridge(bridge); + bus = bridge->bus; controller->root_bus = bus; next_busno = bus->busn_res.end + 1; } - /* Do machine dependent PCI interrupt routing */ - pci_fixup_irqs(pci_common_swizzle, tile_map_irq); - /* * This comes from the generic Linux PCI driver. * -- 2.20.1