From ec1a454d6136b93e26902ead21025efc08047d05 Mon Sep 17 00:00:00 2001 From: Jon Hunter <jonathanh@nvidia.com> Date: Tue, 10 May 2016 16:14:38 +0100 Subject: [PATCH] irqchip/gic: Don't unnecessarily write the IRQ configuration If the interrupt configuration matches the current configuration, then don't bother writing the configuration again. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> --- drivers/irqchip/irq-gic-common.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/irqchip/irq-gic-common.c b/drivers/irqchip/irq-gic-common.c index f174ce0ca361..ffff5a45f1e3 100644 --- a/drivers/irqchip/irq-gic-common.c +++ b/drivers/irqchip/irq-gic-common.c @@ -50,13 +50,17 @@ int gic_configure_irq(unsigned int irq, unsigned int type, else if (type & IRQ_TYPE_EDGE_BOTH) val |= confmask; + /* If the current configuration is the same, then we are done */ + if (val == oldval) + return 0; + /* * Write back the new configuration, and possibly re-enable - * the interrupt. If we tried to write a new configuration and failed, + * the interrupt. If we fail to write a new configuration, * return an error. */ writel_relaxed(val, base + GIC_DIST_CONFIG + confoff); - if (readl_relaxed(base + GIC_DIST_CONFIG + confoff) != val && val != oldval) + if (readl_relaxed(base + GIC_DIST_CONFIG + confoff) != val) ret = -EINVAL; if (sync_access) -- GitLab