irqchip/gic: Add helper functions for GIC setup and teardown

Move the code that sets-up a GIC via device-tree into it's own
function and add a generic function for GIC teardown that can be used
for both device-tree and ACPI to unmap the GIC memory.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 42 insertions, 19 deletions

diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index f4c14f9ca15b..113e2d02c812 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -1197,6 +1197,17 @@ void __init gic_init(unsigned int gic_nr, int irq_start,
         __gic_init_bases(gic, irq_start, NULL);
 }
 
+static void gic_teardown(struct gic_chip_data *gic)
+{
+        if (WARN_ON(!gic))
+                return;
+
+        if (gic->raw_dist_base)
+                iounmap(gic->raw_dist_base);
+        if (gic->raw_cpu_base)
+                iounmap(gic->raw_cpu_base);
+}
+
 #ifdef CONFIG_OF
 static int gic_cnt __initdata;
 
@@ -1238,6 +1249,30 @@ static bool gic_check_eoimode(struct device_node *node, void __iomem **base)
         return true;
 }
 
+static int gic_of_setup(struct gic_chip_data *gic, struct device_node *node)
+{
+        if (!gic || !node)
+                return -EINVAL;
+
+        gic->raw_dist_base = of_iomap(node, 0);
+        if (WARN(!gic->raw_dist_base, "unable to map gic dist registers\n"))
+                goto error;
+
+        gic->raw_cpu_base = of_iomap(node, 1);
+        if (WARN(!gic->raw_cpu_base, "unable to map gic cpu registers\n"))
+                goto error;
+
+        if (of_property_read_u32(node, "cpu-offset", &gic->percpu_offset))
+                gic->percpu_offset = 0;
+
+        return 0;
+
+error:
+        gic_teardown(gic);
+
+        return -ENOMEM;
+}
+
 int __init
 gic_of_init(struct device_node *node, struct device_node *parent)
 {
@@ -1252,15 +1287,9 @@ gic_of_init(struct device_node *node, struct device_node *parent)
 
         gic = &gic_data[gic_cnt];
 
-        gic->raw_dist_base = of_iomap(node, 0);
-        if (WARN(!gic->raw_dist_base, "unable to map gic dist registers\n"))
-                return -ENOMEM;
-
-        gic->raw_cpu_base = of_iomap(node, 1);
-        if (WARN(!gic->raw_cpu_base, "unable to map gic cpu registers\n")) {
-                iounmap(gic->raw_dist_base);
-                return -ENOMEM;
-        }
+        ret = gic_of_setup(gic, node);
+        if (ret)
+                return ret;
 
         /*
          * Disable split EOI/Deactivate if either HYP is not available
@@ -1269,13 +1298,9 @@ gic_of_init(struct device_node *node, struct device_node *parent)
         if (gic_cnt == 0 && !gic_check_eoimode(node, &gic->raw_cpu_base))
                 static_key_slow_dec(&supports_deactivate);
 
-        if (of_property_read_u32(node, "cpu-offset", &gic->percpu_offset))
-                gic->percpu_offset = 0;
-
         ret = __gic_init_bases(gic, -1, &node->fwnode);
         if (ret) {
-                iounmap(gic->raw_dist_base);
-                iounmap(gic->raw_cpu_base);
+                gic_teardown(gic);
                 return ret;
         }
 
@@ -1388,7 +1413,7 @@ static int __init gic_v2_acpi_init(struct acpi_subtable_header *header,
                                      ACPI_GICV2_DIST_MEM_SIZE);
         if (!gic->raw_dist_base) {
                 pr_err("Unable to map GICD registers\n");
-                iounmap(gic->raw_cpu_base);
+                gic_teardown(gic);
                 return -ENOMEM;
         }
 
@@ -1406,8 +1431,7 @@ static int __init gic_v2_acpi_init(struct acpi_subtable_header *header,
         domain_handle = irq_domain_alloc_fwnode(gic->raw_dist_base);
         if (!domain_handle) {
                 pr_err("Unable to allocate domain handle\n");
-                iounmap(gic->raw_cpu_base);
-                iounmap(gic->raw_dist_base);
+                gic_teardown(gic);
                 return -ENOMEM;
         }
 
@@ -1415,8 +1439,7 @@ static int __init gic_v2_acpi_init(struct acpi_subtable_header *header,
         if (ret) {
                 pr_err("Failed to initialise GIC\n");
                 irq_domain_free_fwnode(domain_handle);
-                iounmap(gic->raw_cpu_base);
-                iounmap(gic->raw_dist_base);
+                gic_teardown(gic);
                 return ret;
         }