ARM64: Round-Robin dispatch IRQs between CPUs.

IRQ-CPU mapping is round robined on ARM64 to increase
concurrency and allow multiple interrupts to be serviced
at a time.  This reduces the need for FIQ.

Signed-off-by: Michael Zoran <mzoran@crowfest.net>

diff --git a/drivers/irqchip/irq-bcm2835.c b/drivers/irqchip/irq-bcm2835.c
index 4dbb4b1..8950deb 100644 (file)
--- a/drivers/irqchip/irq-bcm2835.c
+++ b/drivers/irqchip/irq-bcm2835.c
@@ -154,10 +154,23 @@ static void armctrl_unmask_irq(struct irq_data *d)
        }
 }
 
+#ifdef CONFIG_ARM64
+void bcm2836_arm_irqchip_spin_gpu_irq(void);
+
+static void armctrl_ack_irq(struct irq_data *d)
+{
+       bcm2836_arm_irqchip_spin_gpu_irq();
+}
+
+#endif
+
 static struct irq_chip armctrl_chip = {
        .name = "ARMCTRL-level",
        .irq_mask = armctrl_mask_irq,
-       .irq_unmask = armctrl_unmask_irq
+       .irq_unmask = armctrl_unmask_irq,
+#ifdef CONFIG_ARM64
+       .irq_ack    = armctrl_ack_irq
+#endif
 };
 
 static int armctrl_xlate(struct irq_domain *d, struct device_node *ctrlr,

diff --git a/drivers/irqchip/irq-bcm2836.c b/drivers/irqchip/irq-bcm2836.c
index 867c3b4..f9da3f2 100644 (file)
--- a/drivers/irqchip/irq-bcm2836.c
+++ b/drivers/irqchip/irq-bcm2836.c
@@ -87,6 +87,27 @@ static void bcm2836_arm_irqchip_unmask_gpu_irq(struct irq_data *d)
 {
 }
 
+#ifdef CONFIG_ARM64
+
+void bcm2836_arm_irqchip_spin_gpu_irq(void)
+{
+       u32 i;
+       void __iomem *gpurouting = (intc.base + LOCAL_GPU_ROUTING);
+       u32 routing_val = readl(gpurouting);
+
+       for (i = 1; i <= 3; i++) {
+               u32 new_routing_val = (routing_val + i) & 3;
+
+               if (cpu_active(new_routing_val)) {
+                       writel(new_routing_val, gpurouting);
+                       return;
+               }
+       }
+}
+EXPORT_SYMBOL(bcm2836_arm_irqchip_spin_gpu_irq);
+
+#endif
+
 static struct irq_chip bcm2836_arm_irqchip_gpu = {
        .name           = "bcm2836-gpu",
        .irq_mask       = bcm2836_arm_irqchip_mask_gpu_irq,