diff options
authorTomasz Figa <t.figa@samsung.com>2014-07-17 17:23:44 +0200
committerJason Cooper <jason@lakedaemon.net>2014-07-18 13:13:41 +0000
commit29e697b11853d3f83b1864ae385abdad4aa2c361 (patch)
parent144cb08864ed44be52d8634ac69cd98e5efcf527 (diff)
irqchip: gic: Fix core ID calculation when topology is read from DT
Certain GIC implementation, namely those found on earlier, single cluster, Exynos SoCs, have registers mapped without per-CPU banking, which means that the driver needs to use different offset for each CPU. Currently the driver calculates the offset by multiplying value returned by cpu_logical_map() by CPU offset parsed from DT. This is correct when CPU topology is not specified in DT and aforementioned function returns core ID alone. However when DT contains CPU topology, the function changes to return cluster ID as well, which is non-zero on mentioned SoCs and so breaks the calculation in GIC driver. This patch fixes this by masking out cluster ID in CPU offset calculation so that only core ID is considered. Multi-cluster Exynos SoCs already have banked GIC implementations, so this simple fix should be enough. Reported-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Tomasz Figa <t.figa@samsung.com> Fixes: db0d4db22a78d ("ARM: gic: allow GIC to support non-banked setups") Cc: <stable@vger.kernel.org> # v3.3+ Link: https://lkml.kernel.org/r/1405610624-18722-1-git-send-email-t.figa@samsung.com Signed-off-by: Jason Cooper <jason@lakedaemon.net>
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index 66ed8922dab2..7c131cf7cc13 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -42,6 +42,7 @@
#include <linux/irqchip/chained_irq.h>
#include <linux/irqchip/arm-gic.h>
+#include <asm/cputype.h>
#include <asm/irq.h>
#include <asm/exception.h>
#include <asm/smp_plat.h>
@@ -954,7 +955,9 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start,
for_each_possible_cpu(cpu) {
- unsigned long offset = percpu_offset * cpu_logical_map(cpu);
+ u32 mpidr = cpu_logical_map(cpu);
+ u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+ unsigned long offset = percpu_offset * core_id;
*per_cpu_ptr(gic->dist_base.percpu_base, cpu) = dist_base + offset;
*per_cpu_ptr(gic->cpu_base.percpu_base, cpu) = cpu_base + offset;

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