From 73bd063ca03493f44e0700cc08824093da9741bc Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 25 Nov 2022 00:26:23 +0100 Subject: [PATCH] PCI/MSI: Provide prepare_desc() MSI domain op The setup of MSI descriptors for PCI/MSI-X interrupts depends partially on the MSI index for which the descriptor is initialized. Dynamic MSI-X vector allocation post MSI-X enablement allows to allocate vectors at a given index or at any free index in the available table range. The latter requires that the descriptor is initialized after the MSI core has chosen an index. Implement the prepare_desc() op in the PCI/MSI-X specific msi_domain_ops which is invoked before the core interrupt descriptor and the associated Linux interrupt number is allocated. That callback is also provided for the upcoming PCI/IMS implementations so the implementation specific interrupt domain can do their domain specific initialization of the MSI descriptors. Signed-off-by: Thomas Gleixner Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Acked-by: Bjorn Helgaas Acked-by: Marc Zyngier Link: https://lore.kernel.org/r/20221124232326.673658806@linutronix.de --- drivers/pci/msi/irqdomain.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c index 473640381f92..8afaef10b939 100644 --- a/drivers/pci/msi/irqdomain.c +++ b/drivers/pci/msi/irqdomain.c @@ -202,6 +202,14 @@ static void pci_irq_unmask_msix(struct irq_data *data) pci_msix_unmask(irq_data_get_msi_desc(data)); } +static void pci_msix_prepare_desc(struct irq_domain *domain, msi_alloc_info_t *arg, + struct msi_desc *desc) +{ + /* Don't fiddle with preallocated MSI descriptors */ + if (!desc->pci.mask_base) + msix_prepare_msi_desc(to_pci_dev(desc->dev), desc); +} + static const struct msi_domain_template pci_msix_template = { .chip = { .name = "PCI-MSIX", @@ -212,6 +220,7 @@ static const struct msi_domain_template pci_msix_template = { }, .ops = { + .prepare_desc = pci_msix_prepare_desc, .set_desc = pci_device_domain_set_desc, },