ARM: 7177/1: GIC: avoid skipping non-existent PPIs in irq_start calculation

Commit 4294f8baa ("ARM: gic: add irq_domain support") defines irq_start
as irq_start = (irq_start & ~31) + 16; On a platform with a GIC and a
CPU without PPIs, this results in irq_start being off by 16.

This patch fixes gic_init so that we only carve out a PPI space when
PPIs exist for the GIC being initialised.

Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index 43240f315dea74740f96df9bd6d55909d3add0fd..410a546060a2eecf82859d76c528223e8796f9f4 100644 (file)
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -582,13 +582,16 @@ void __init gic_init(unsigned int gic_nr, int irq_start,
         * For primary GICs, skip over SGIs.
         * For secondary GICs, skip over PPIs, too.
         */
+       domain->hwirq_base = 32;
        if (gic_nr == 0) {
                gic_cpu_base_addr = cpu_base;
-               domain->hwirq_base = 16;
-               if (irq_start > 0)
-                       irq_start = (irq_start & ~31) + 16;
-       } else
-               domain->hwirq_base = 32;
+
+               if ((irq_start & 31) > 0) {
+                       domain->hwirq_base = 16;
+                       if (irq_start != -1)
+                               irq_start = (irq_start & ~31) + 16;
+               }
+       }
 
        /*
         * Find out how many interrupts are supported.