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 --- include/linux/pci.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/pci.h b/include/linux/pci.h index c20211e59a57..24306504226a 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -2344,6 +2344,7 @@ int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off, struct device_node; struct irq_domain; struct irq_domain *pci_host_bridge_of_msi_domain(struct pci_bus *bus); +bool pci_host_of_has_msi_map(struct device *dev); /* Arch may override this (weak) */ struct device_node *pcibios_get_phb_of_node(struct pci_bus *bus); @@ -2351,6 +2352,7 @@ struct device_node *pcibios_get_phb_of_node(struct pci_bus *bus); #else /* CONFIG_OF */ static inline struct irq_domain * pci_host_bridge_of_msi_domain(struct pci_bus *bus) { return NULL; } +static inline bool pci_host_of_has_msi_map(struct device *dev) { return false; } #endif /* CONFIG_OF */ static inline struct device_node * -- cgit v1.2.3