diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2015-10-02 14:43:06 +0100 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2015-10-16 13:07:16 +0100 |
| commit | 54fa97eeb9e22b47d68b67ee00987afa7fbc2178 (patch) | |
| tree | bf5cbab9a60df9291dcc92592f21a1c52cc593ee | |
| parent | 098259eb16675a83e1d6ea31e06dc3ec152810a2 (diff) | |
PCI/MSI: Allow the MSI domain to be device-specific
So far, we've always considered that for a given PCI device, its
MSI controller was either set by the architecture-specific
pcibios hook, or simply inherited from the host bridge.
This doesn't cover things like firmware-defined topologies like
msi-map (DT) or IORT (ACPI), which can provide information about
which MSI controller to use on a per-device basis.
This patch adds the necessary hook into the MSI code to allow this
feature, and provides the msi-map functionnality as a first
implementation.
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| -rw-r--r-- | drivers/pci/msi.c | 17 | ||||
| -rw-r--r-- | drivers/pci/probe.c | 8 | ||||
| -rw-r--r-- | include/linux/msi.h | 6 |
3 files changed, 31 insertions, 0 deletions
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 5ab5c4f8dcb0..4cd6f3abcecf 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -1359,4 +1359,21 @@ u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev) return rid; } + +/** + * pci_msi_get_device_domain - Get the MSI domain for a given PCI device + * @pdev: The PCI device + * + * Use the firmware data to find a device-specific MSI domain + * (i.e. not one that is ste as a default). + * + * Returns: The coresponding MSI domain or NULL if none has been found. + */ +struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) +{ + u32 rid = 0; + + pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid); + return of_msi_map_get_device_domain(&pdev->dev, rid); +} #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 7c333f8c2327..f14a970b61fa 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1639,6 +1639,14 @@ static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev) if (d) return d; + /* + * Let's see if we have a firmware interface able to provide + * the domain. + */ + d = pci_msi_get_device_domain(dev); + if (d) + return d; + return NULL; } diff --git a/include/linux/msi.h b/include/linux/msi.h index 87723751054d..0b4460374020 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -295,6 +295,12 @@ irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev, 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); +struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev); +#else +static inline struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) +{ + return NULL; +} #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ #endif /* LINUX_MSI_H */ |