iommu/amd: Add IOAPIC remapping routines

Add the routine to setup interrupt remapping for ioapic
interrupts. Also add a routine to change the affinity of an
irq and to free an irq allocation for interrupt remapping.
The last two functions will also be used for MSI interrupts.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

drivers/iommu/amd_iommu.c

@@ -4000,4 +4000,130 @@ static void free_irte(u16 devid, int index)
 	iommu_completion_wait(iommu);
 }
 
+static int setup_ioapic_entry(int irq, struct IO_APIC_route_entry *entry,
+			      unsigned int destination, int vector,
+			      struct io_apic_irq_attr *attr)
+{
+	struct irq_remap_table *table;
+	struct irq_2_iommu *irte_info;
+	struct irq_cfg *cfg;
+	union irte irte;
+	int ioapic_id;
+	int index;
+	int devid;
+	int ret;
+
+	cfg = irq_get_chip_data(irq);
+	if (!cfg)
+		return -EINVAL;
+
+	irte_info = &cfg->irq_2_iommu;
+	ioapic_id = mpc_ioapic_id(attr->ioapic);
+	devid     = get_ioapic_devid(ioapic_id);
+
+	if (devid < 0)
+		return devid;
+
+	table = get_irq_table(devid, true);
+	if (table == NULL)
+		return -ENOMEM;
+
+	index = attr->ioapic_pin;
+
+	/* Setup IRQ remapping info */
+	irte_info->sub_handle = devid;
+	irte_info->irte_index = index;
+	irte_info->iommu      = (void *)cfg;
+
+	/* Setup IRTE for IOMMU */
+	irte.val		= 0;
+	irte.fields.vector      = vector;
+	irte.fields.int_type    = apic->irq_delivery_mode;
+	irte.fields.destination = destination;
+	irte.fields.dm          = apic->irq_dest_mode;
+	irte.fields.valid       = 1;
+
+	ret = modify_irte(devid, index, irte);
+	if (ret)
+		return ret;
+
+	/* Setup IOAPIC entry */
+	memset(entry, 0, sizeof(*entry));
+
+	entry->vector        = index;
+	entry->mask          = 0;
+	entry->trigger       = attr->trigger;
+	entry->polarity      = attr->polarity;
+
+	/*
+	 * Mask level triggered irqs.
+	 * Use IRQ_DELAYED_DISABLE for edge triggered irqs.
+	 */
+	if (attr->trigger)
+		entry->mask = 1;
+
+	return 0;
+}
+
+static int set_affinity(struct irq_data *data, const struct cpumask *mask,
+			bool force)
+{
+	struct irq_2_iommu *irte_info;
+	unsigned int dest, irq;
+	struct irq_cfg *cfg;
+	union irte irte;
+	int err;
+
+	if (!config_enabled(CONFIG_SMP))
+		return -1;
+
+	cfg       = data->chip_data;
+	irq       = data->irq;
+	irte_info = &cfg->irq_2_iommu;
+
+	if (!cpumask_intersects(mask, cpu_online_mask))
+		return -EINVAL;
+
+	if (get_irte(irte_info->sub_handle, irte_info->irte_index, &irte))
+		return -EBUSY;
+
+	if (assign_irq_vector(irq, cfg, mask))
+		return -EBUSY;
+
+	err = apic->cpu_mask_to_apicid_and(cfg->domain, mask, &dest);
+	if (err) {
+		if (assign_irq_vector(irq, cfg, data->affinity))
+			pr_err("AMD-Vi: Failed to recover vector for irq %d\n", irq);
+		return err;
+	}
+
+	irte.fields.vector      = cfg->vector;
+	irte.fields.destination = dest;
+
+	modify_irte(irte_info->sub_handle, irte_info->irte_index, irte);
+
+	if (cfg->move_in_progress)
+		send_cleanup_vector(cfg);
+
+	cpumask_copy(data->affinity, mask);
+
+	return 0;
+}
+
+static int free_irq(int irq)
+{
+	struct irq_2_iommu *irte_info;
+	struct irq_cfg *cfg;
+
+	cfg = irq_get_chip_data(irq);
+	if (!cfg)
+		return -EINVAL;
+
+	irte_info = &cfg->irq_2_iommu;
+
+	free_irte(irte_info->sub_handle, irte_info->irte_index);
+
+	return 0;
+}
+
 #endif