irqchip/gicv3-its: Cleanup for ITS domain initialization

There is no point to initialize ITS without having msi-controller
property in corresponding DT node. However, its_probe is checking
msi-controller presence at the end, so we can save our time and do that
check prior to its_probe call. Also, for the code clarity purpose,
we put domain initialization to separate function.

Signed-off-by: Tomasz Nowicki <tn@semihalf.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 36b9c28..943442d 100644 (file)
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1614,13 +1614,37 @@ static void its_enable_quirks(struct its_node *its)
        gic_enable_quirks(iidr, its_quirks, its);
 }
 
+static int its_init_domain(struct device_node *node, struct its_node *its,
+                          struct irq_domain *parent)
+{
+       struct irq_domain *inner_domain;
+       struct msi_domain_info *info;
+
+       info = kzalloc(sizeof(*info), GFP_KERNEL);
+       if (!info)
+               return -ENOMEM;
+
+       inner_domain = irq_domain_add_tree(node, &its_domain_ops, its);
+       if (!inner_domain) {
+               kfree(info);
+               return -ENOMEM;
+       }
+
+       inner_domain->parent = parent;
+       inner_domain->bus_token = DOMAIN_BUS_NEXUS;
+       info->ops = &its_msi_domain_ops;
+       info->data = its;
+       inner_domain->host_data = info;
+
+       return 0;
+}
+
 static int __init its_probe(struct device_node *node,
                            struct irq_domain *parent)
 {
        struct resource res;
        struct its_node *its;
        void __iomem *its_base;
-       struct irq_domain *inner_domain;
        u32 val;
        u64 baser, tmp;
        int err;
@@ -1712,28 +1736,9 @@ static int __init its_probe(struct device_node *node,
        writeq_relaxed(0, its->base + GITS_CWRITER);
        writel_relaxed(GITS_CTLR_ENABLE, its->base + GITS_CTLR);
 
-       if (of_property_read_bool(node, "msi-controller")) {
-               struct msi_domain_info *info;
-
-               info = kzalloc(sizeof(*info), GFP_KERNEL);
-               if (!info) {
-                       err = -ENOMEM;
-                       goto out_free_tables;
-               }
-
-               inner_domain = irq_domain_add_tree(node, &its_domain_ops, its);
-               if (!inner_domain) {
-                       err = -ENOMEM;
-                       kfree(info);
-                       goto out_free_tables;
-               }
-
-               inner_domain->parent = parent;
-               inner_domain->bus_token = DOMAIN_BUS_NEXUS;
-               info->ops = &its_msi_domain_ops;
-               info->data = its;
-               inner_domain->host_data = info;
-       }
+       err = its_init_domain(node, its, parent);
+       if (err)
+               goto out_free_tables;
 
        spin_lock(&its_lock);
        list_add(&its->entry, &its_nodes);
@@ -1784,6 +1789,12 @@ int __init its_init(struct device_node *node, struct rdists *rdists,
 
        for (np = of_find_matching_node(node, its_device_id); np;
             np = of_find_matching_node(np, its_device_id)) {
+               if (!of_property_read_bool(np, "msi-controller")) {
+                       pr_warn("%s: no msi-controller property, ITS ignored\n",
+                               np->full_name);
+                       continue;
+               }
+
                its_probe(np, parent_domain);
        }