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path: root/drivers/irqchip/irq-gic-v3-its-pci-msi.c
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Diffstat (limited to 'drivers/irqchip/irq-gic-v3-its-pci-msi.c')
-rw-r--r--drivers/irqchip/irq-gic-v3-its-pci-msi.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-gic-v3-its-pci-msi.c b/drivers/irqchip/irq-gic-v3-its-pci-msi.c
new file mode 100644
index 0000000..cf351c6
--- /dev/null
+++ b/drivers/irqchip/irq-gic-v3-its-pci-msi.c
@@ -0,0 +1,140 @@
+/*
+ * Copyright (C) 2013-2015 ARM Limited, All Rights Reserved.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/msi.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_pci.h>
+
+static void its_mask_msi_irq(struct irq_data *d)
+{
+ pci_msi_mask_irq(d);
+ irq_chip_mask_parent(d);
+}
+
+static void its_unmask_msi_irq(struct irq_data *d)
+{
+ pci_msi_unmask_irq(d);
+ irq_chip_unmask_parent(d);
+}
+
+static struct irq_chip its_msi_irq_chip = {
+ .name = "ITS-MSI",
+ .irq_unmask = its_unmask_msi_irq,
+ .irq_mask = its_mask_msi_irq,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_write_msi_msg = pci_msi_domain_write_msg,
+};
+
+struct its_pci_alias {
+ struct pci_dev *pdev;
+ u32 dev_id;
+ u32 count;
+};
+
+static int its_pci_msi_vec_count(struct pci_dev *pdev)
+{
+ int msi, msix;
+
+ msi = max(pci_msi_vec_count(pdev), 0);
+ msix = max(pci_msix_vec_count(pdev), 0);
+
+ return max(msi, msix);
+}
+
+static int its_get_pci_alias(struct pci_dev *pdev, u16 alias, void *data)
+{
+ struct its_pci_alias *dev_alias = data;
+
+ dev_alias->dev_id = alias;
+ if (pdev != dev_alias->pdev)
+ dev_alias->count += its_pci_msi_vec_count(dev_alias->pdev);
+
+ return 0;
+}
+
+static int its_pci_msi_prepare(struct irq_domain *domain, struct device *dev,
+ int nvec, msi_alloc_info_t *info)
+{
+ struct pci_dev *pdev;
+ struct its_pci_alias dev_alias;
+ struct msi_domain_info *msi_info;
+
+ if (!dev_is_pci(dev))
+ return -EINVAL;
+
+ msi_info = msi_get_domain_info(domain->parent);
+
+ pdev = to_pci_dev(dev);
+ dev_alias.pdev = pdev;
+ dev_alias.count = nvec;
+
+ pci_for_each_dma_alias(pdev, its_get_pci_alias, &dev_alias);
+
+ /* ITS specific DeviceID, as the core ITS ignores dev. */
+ info->scratchpad[0].ul = dev_alias.dev_id;
+
+ return msi_info->ops->msi_prepare(domain->parent,
+ dev, dev_alias.count, info);
+}
+
+static struct msi_domain_ops its_pci_msi_ops = {
+ .msi_prepare = its_pci_msi_prepare,
+};
+
+static struct msi_domain_info its_pci_msi_domain_info = {
+ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX),
+ .ops = &its_pci_msi_ops,
+ .chip = &its_msi_irq_chip,
+};
+
+static struct of_device_id its_device_id[] = {
+ { .compatible = "arm,gic-v3-its", },
+ {},
+};
+
+static int __init its_pci_msi_init(void)
+{
+ struct device_node *np;
+ struct irq_domain *parent;
+
+ for (np = of_find_matching_node(NULL, its_device_id); np;
+ np = of_find_matching_node(np, its_device_id)) {
+ if (!of_property_read_bool(np, "msi-controller"))
+ continue;
+
+ parent = irq_find_matching_host(np, DOMAIN_BUS_NEXUS);
+ if (!parent || !msi_get_domain_info(parent)) {
+ pr_err("%s: unable to locate ITS domain\n",
+ np->full_name);
+ continue;
+ }
+
+ if (!pci_msi_create_irq_domain(np, &its_pci_msi_domain_info,
+ parent)) {
+ pr_err("%s: unable to create PCI domain\n",
+ np->full_name);
+ continue;
+ }
+
+ pr_info("PCI/MSI: %s domain created\n", np->full_name);
+ }
+
+ return 0;
+}
+early_initcall(its_pci_msi_init);