From 34dd263fce3114147f21698f8e55e05b9e8185bd Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Sun, 29 Nov 2020 13:52:08 +0000 Subject: irqchip/gic-v3-its: Flag device allocation as proxied if behind a PCI bridge An aliasing PCI bridge is another case where we should flag the corresponding allocation as "proxied", as MSIs are coming with the bridge's RID, and not the originating device's. Signed-off-by: Marc Zyngier Tested-by: John Garry Link: https://lore.kernel.org/r/20201129135208.680293-4-maz@kernel.org --- drivers/irqchip/irq-gic-v3-its-pci-msi.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'drivers/irqchip/irq-gic-v3-its-pci-msi.c') diff --git a/drivers/irqchip/irq-gic-v3-its-pci-msi.c b/drivers/irqchip/irq-gic-v3-its-pci-msi.c index 87711e0f8014..ad2810c017ed 100644 --- a/drivers/irqchip/irq-gic-v3-its-pci-msi.c +++ b/drivers/irqchip/irq-gic-v3-its-pci-msi.c @@ -67,11 +67,16 @@ static int its_pci_msi_prepare(struct irq_domain *domain, struct device *dev, /* * If pdev is downstream of any aliasing bridges, take an upper * bound of how many other vectors could map to the same DevID. + * Also tell the ITS that the signalling will come from a proxy + * device, and that special allocation rules apply. */ pci_for_each_dma_alias(pdev, its_get_pci_alias, &alias_dev); - if (alias_dev != pdev && alias_dev->subordinate) - pci_walk_bus(alias_dev->subordinate, its_pci_msi_vec_count, - &alias_count); + if (alias_dev != pdev) { + if (alias_dev->subordinate) + pci_walk_bus(alias_dev->subordinate, + its_pci_msi_vec_count, &alias_count); + info->flags |= MSI_ALLOC_FLAGS_PROXY_DEVICE; + } /* ITS specific DeviceID, as the core ITS ignores dev. */ info->scratchpad[0].ul = pci_msi_domain_get_msi_rid(domain, pdev); -- cgit