From b6eec9b717d4dcb39ef024b8a3b619a32468b01e Mon Sep 17 00:00:00 2001 From: David Daney Date: Thu, 8 Oct 2015 15:10:49 -0700 Subject: [PATCH] PCI/MSI: Add helper function pci_msi_domain_get_msi_rid(). Add pci_msi_domain_get_msi_rid() to return the MSI requester id (RID). Initially needed by gic-v3 based systems. It will be used by follow on patch to drivers/irqchip/irq-gic-v3-its-pci-msi.c Initially supports mapping the RID via OF device tree. In the future, this could be extended to use ACPI _IORT tables as well. Reviewed-by: Marc Zyngier Acked-by: Bjorn Helgaas Signed-off-by: David Daney Signed-off-by: Marc Zyngier --- drivers/pci/msi.c | 32 ++++++++++++++++++++++++++++++++ include/linux/msi.h | 1 + 2 files changed, 33 insertions(+) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index ddd59fe786f8..5ab5c4f8dcb0 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -20,6 +20,7 @@ #include #include #include +#include #include "pci.h" @@ -1327,4 +1328,35 @@ struct irq_domain *pci_msi_create_default_irq_domain(struct fwnode_handle *fwnod return domain; } + +static int get_msi_id_cb(struct pci_dev *pdev, u16 alias, void *data) +{ + u32 *pa = data; + + *pa = alias; + return 0; +} +/** + * pci_msi_domain_get_msi_rid - Get the MSI requester id (RID) + * @domain: The interrupt domain + * @pdev: The PCI device. + * + * The RID for a device is formed from the alias, with a firmware + * supplied mapping applied + * + * Returns: The RID. + */ +u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev) +{ + struct device_node *of_node; + u32 rid = 0; + + pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid); + + of_node = irq_domain_get_of_node(domain); + if (of_node) + rid = of_msi_map_rid(&pdev->dev, of_node, rid); + + return rid; +} #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ diff --git a/include/linux/msi.h b/include/linux/msi.h index 32a24b9a9556..87723751054d 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -294,6 +294,7 @@ irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev, struct msi_desc *desc); int pci_msi_domain_check_cap(struct irq_domain *domain, struct msi_domain_info *info, struct device *dev); +u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev); #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ #endif /* LINUX_MSI_H */ -- 2.20.1