From 85aabbd7b315c65673084b6227bee92c00405239 Mon Sep 17 00:00:00 2001 From: Jean-Philippe Brucker Date: Mon, 10 May 2021 19:31:30 +0200 Subject: PCI/MSI: Fix MSIs for generic hosts that use device-tree's "msi-map" Since commit 9ec37efb8783 ("PCI/MSI: Make pci_host_common_probe() declare its reliance on MSI domains"), platforms that rely on the "msi-map" device-tree property don't get MSIs anymore. On the Arm Fast Model for example [1], the host bridge doesn't have a "msi-parent" property since it doesn't itself generate MSIs, and so doesn't get a MSI domain. It has an "msi-map" property instead to describe MSI controllers of child devices. As a result, due to the new msi_domain check in pci_register_host_bridge(), the whole bus gets PCI_BUS_FLAGS_NO_MSI. Check whether the root complex has an "msi-map" property before giving up on MSIs. [1] arch/arm64/boot/dts/arm/fvp-base-revc.dts Fixes: 9ec37efb8783 ("PCI/MSI: Make pci_host_common_probe() declare its reliance on MSI domains") Link: https://lore.kernel.org/r/20210510173129.750496-1-jean-philippe@linaro.org Signed-off-by: Jean-Philippe Brucker Signed-off-by: Bjorn Helgaas Acked-by: Marc Zyngier --- drivers/pci/probe.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/pci/probe.c') diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 3a62d09b8869..275204646c68 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -925,7 +925,8 @@ static int pci_register_host_bridge(struct pci_host_bridge *bridge) device_enable_async_suspend(bus->bridge); pci_set_bus_of_node(bus); pci_set_bus_msi_domain(bus); - if (bridge->msi_domain && !dev_get_msi_domain(&bus->dev)) + if (bridge->msi_domain && !dev_get_msi_domain(&bus->dev) && + !pci_host_of_has_msi_map(parent)) bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI; if (!parent) -- cgit v1.2.3