These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / irqchip / irq-gic-v3-its-pci-msi.c

diff --git a/kernel/drivers/irqchip/irq-gic-v3-its-pci-msi.c b/kernel/drivers/irqchip/irq-gic-v3-its-pci-msi.c
new file mode 100644 (file)
index 0000000..aee60ed
--- /dev/null
+++ b/kernel/drivers/irqchip/irq-gic-v3-its-pci-msi.c
@@ -0,0 +1,139 @@
+/*
+ * 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             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;
+
+       if (pdev != dev_alias->pdev)
+               dev_alias->count += its_pci_msi_vec_count(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 = pci_msi_domain_get_msi_rid(domain, pdev);
+
+       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(of_node_to_fwnode(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);