iommu/amd: Implement MSI routines for interrupt remapping

Add routines to setup interrupt remapping for MSI
interrupts.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

1 files changed, 74 insertions, 0 deletions

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 886b4c7fba72..bcf48156868b 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -4126,4 +4126,78 @@ static int free_irq(int irq)
         return 0;
 }
 
+static void compose_msi_msg(struct pci_dev *pdev,
+                            unsigned int irq, unsigned int dest,
+                            struct msi_msg *msg, u8 hpet_id)
+{
+        struct irq_2_iommu *irte_info;
+        struct irq_cfg *cfg;
+        union irte irte;
+
+        cfg = irq_get_chip_data(irq);
+        if (!cfg)
+                return;
+
+        irte_info = &cfg->irq_2_iommu;
+
+        irte.val                = 0;
+        irte.fields.vector      = cfg->vector;
+        irte.fields.int_type    = apic->irq_delivery_mode;
+        irte.fields.destination = dest;
+        irte.fields.dm          = apic->irq_dest_mode;
+        irte.fields.valid       = 1;
+
+        modify_irte(irte_info->sub_handle, irte_info->irte_index, irte);
+
+        msg->address_hi = MSI_ADDR_BASE_HI;
+        msg->address_lo = MSI_ADDR_BASE_LO;
+        msg->data       = irte_info->irte_index;
+}
+
+static int msi_alloc_irq(struct pci_dev *pdev, int irq, int nvec)
+{
+        struct irq_cfg *cfg;
+        int index;
+        u16 devid;
+
+        if (!pdev)
+                return -EINVAL;
+
+        cfg = irq_get_chip_data(irq);
+        if (!cfg)
+                return -EINVAL;
+
+        devid = get_device_id(&pdev->dev);
+        index = alloc_irq_index(cfg, devid, nvec);
+
+        return index < 0 ? MAX_IRQS_PER_TABLE : index;
+}
+
+static int msi_setup_irq(struct pci_dev *pdev, unsigned int irq,
+                         int index, int offset)
+{
+        struct irq_2_iommu *irte_info;
+        struct irq_cfg *cfg;
+        u16 devid;
+
+        if (!pdev)
+                return -EINVAL;
+
+        cfg = irq_get_chip_data(irq);
+        if (!cfg)
+                return -EINVAL;
+
+        if (index >= MAX_IRQS_PER_TABLE)
+                return 0;
+
+        devid           = get_device_id(&pdev->dev);
+        irte_info       = &cfg->irq_2_iommu;
+
+        irte_info->sub_handle = devid;
+        irte_info->irte_index = index + offset;
+        irte_info->iommu      = (void *)cfg;
+
+        return 0;
+}
+
 #endif