1 files changed, 106 insertions, 0 deletions

diff --git a/kernel/drivers/irqchip/irq-gic-v3-its-platform-msi.c b/kernel/drivers/irqchip/irq-gic-v3-its-platform-msi.c
new file mode 100644
index 000000000..470b4aa7d
--- /dev/null
+++ b/kernel/drivers/irqchip/irq-gic-v3-its-platform-msi.c
@@ -0,0 +1,106 @@
+/*
+ * 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/device.h>
+#include <linux/msi.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+
+static struct irq_chip its_pmsi_irq_chip = {
+	.name			= "ITS-pMSI",
+};
+
+static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
+			    int nvec, msi_alloc_info_t *info)
+{
+	struct msi_domain_info *msi_info;
+	u32 dev_id;
+	int ret, index = 0;
+
+	msi_info = msi_get_domain_info(domain->parent);
+
+	/* Suck the DeviceID out of the msi-parent property */
+	do {
+		struct of_phandle_args args;
+
+		ret = of_parse_phandle_with_args(dev->of_node,
+						 "msi-parent", "#msi-cells",
+						 index, &args);
+		if (args.np == irq_domain_get_of_node(domain)) {
+			if (WARN_ON(args.args_count != 1))
+				return -EINVAL;
+			dev_id = args.args[0];
+			break;
+		}
+	} while (!ret);
+
+	if (ret)
+		return ret;
+
+	/* ITS specific DeviceID, as the core ITS ignores dev. */
+	info->scratchpad[0].ul = dev_id;
+
+	return msi_info->ops->msi_prepare(domain->parent,
+					  dev, nvec, info);
+}
+
+static struct msi_domain_ops its_pmsi_ops = {
+	.msi_prepare	= its_pmsi_prepare,
+};
+
+static struct msi_domain_info its_pmsi_domain_info = {
+	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
+	.ops	= &its_pmsi_ops,
+	.chip	= &its_pmsi_irq_chip,
+};
+
+static struct of_device_id its_device_id[] = {
+	{	.compatible	= "arm,gic-v3-its",	},
+	{},
+};
+
+static int __init its_pmsi_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 (!platform_msi_create_irq_domain(of_node_to_fwnode(np),
+						    &its_pmsi_domain_info,
+						    parent)) {
+			pr_err("%s: unable to create platform domain\n",
+			       np->full_name);
+			continue;
+		}
+
+		pr_info("Platform MSI: %s domain created\n", np->full_name);
+	}
+
+	return 0;
+}
+early_initcall(its_pmsi_init);