It is now possible to provide information about which MSI controller to
use on a per-device basis for DT. This patch supply this with ACPI support.
In order to handle MSI domain on per-devices basis we need to add
PCI device requester ID (RID) mapper, MSI domain provider and corresponding
registration:
pci_acpi_msi_domain_get_msi_rid - maps PCI ID and returns MSI RID
pci_acpi_register_msi_rid_mapper - registers RID mapper
pci_acpi_msi_get_device_domain - finds PCI device MSI domain
pci_acpi_register_dev_msi_fwnode_provider - registers MSI domain finder
Then, it is plugged into MSI infrastructure.
To: Bjorn Helgaas <bhelg...@google.com>
To: Rafael J. Wysocki <r...@rjwysocki.net>
Signed-off-by: Tomasz Nowicki <t...@semihalf.com>
---
drivers/pci/msi.c | 10 +++++--
drivers/pci/pci-acpi.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/pci.h | 11 ++++++++
3 files changed, 95 insertions(+), 3 deletions(-)
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index a080f44..07b59a3 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -1364,8 +1364,8 @@ u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain,
struct pci_dev *pdev)
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);
+ rid = of_node ? of_msi_map_rid(&pdev->dev, of_node, rid) :
+ pci_acpi_msi_domain_get_msi_rid(pdev, rid);
return rid;
}
@@ -1381,9 +1381,13 @@ 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)
{
+ struct irq_domain *dom;
u32 rid = 0;
pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
- return of_msi_map_get_device_domain(&pdev->dev, rid);
+ dom = of_msi_map_get_device_domain(&pdev->dev, rid);
+ if (!dom)
+ dom = pci_acpi_msi_get_device_domain(pdev, rid);
+ return dom;
}
#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 9a033e8..26f4552 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -731,6 +731,83 @@ struct irq_domain *pci_host_bridge_acpi_msi_domain(struct
pci_bus *bus)
return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI);
}
+static u32 (*pci_msi_map_dev_rid_cb)(struct pci_dev *pdev, u32 req_id);
+
+/**
+ * pci_acpi_register_msi_rid_mapper - Register callback to map the MSI
+ * requester id (RID)
+ * @fn: Callback mapping a PCI device RID.
+ *
+ * This should be called by irqchip driver, which can provide firmware-defined
+ * topologies about MSI requester id (RID) on a per-device basis.
+ */
+void pci_acpi_register_msi_rid_mapper(u32 (*fn)(struct pci_dev *, u32))
+{
+ pci_msi_map_dev_rid_cb = fn;
+}
+
+/**
+ * pci_acpi_msi_domain_get_msi_rid - Get the MSI requester id (RID) of
+ * a PCI device
+ * @pdev: The PCI device.
+ * @rid_in: The PCI device request ID.
+ *
+ * This function uses the callback function registered by
+ * pci_acpi_register_msi_rid_mapper() to get the device RID based on ACPI
+ * supplied mapping.
+ * This should return rid_in on error or when there is no valid map.
+ */
+u32 pci_acpi_msi_domain_get_msi_rid(struct pci_dev *pdev, u32 rid_in)
+{
+ if (!pci_msi_map_dev_rid_cb)
+ return rid_in;
+
+ return pci_msi_map_dev_rid_cb(pdev, rid_in);
+}
+
+static struct fwnode_handle *(*pci_msi_get_dev_fwnode_cb)(struct pci_dev *pdev,
+ u32 req_id);
+
+/**
+ * pci_acpi_register_dev_msi_fwnode_provider - Register callback to retrieve
+ * domain fwnode on the per-device basis
+ * @fn: Callback matching a device to a fwnode that identifies a PCI
+ * MSI domain.
+ *
+ * This should be called by irqchip driver, which can provide firmware-defined
+ * topologies about which MSI controller to use on a per-device basis.
+ */
+void
+pci_acpi_register_dev_msi_fwnode_provider(
+ struct fwnode_handle *(*fn)(struct pci_dev *, u32))
+{
+ pci_msi_get_dev_fwnode_cb = fn;
+}
