irqchip: armada-370-xp: Add helper for the MSI IRQ handling

Introduce a helper function to handle the MSI interrupts. This makes
the code more readable. In addition, this will allow to introduce a
chained IRQ handler mechanism, which is needed in situations where the
MPIC is used as a slave to another interrupt controller.

Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c
index 5409564..2ba5761 100644 (file)
--- a/drivers/irqchip/irq-armada-370-xp.c
+++ b/drivers/irqchip/irq-armada-370-xp.c
@@ -352,6 +352,34 @@ static struct irq_domain_ops armada_370_xp_mpic_irq_ops = {
        .xlate = irq_domain_xlate_onecell,
 };
 
+#ifdef CONFIG_PCI_MSI
+static void armada_370_xp_handle_msi_irq(struct pt_regs *regs)
+{
+       u32 msimask, msinr;
+
+       msimask = readl_relaxed(per_cpu_int_base +
+                               ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
+               & PCI_MSI_DOORBELL_MASK;
+
+       writel(~msimask, per_cpu_int_base +
+              ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
+
+       for (msinr = PCI_MSI_DOORBELL_START;
+            msinr < PCI_MSI_DOORBELL_END; msinr++) {
+               int irq;
+
+               if (!(msimask & BIT(msinr)))
+                       continue;
+
+               irq = irq_find_mapping(armada_370_xp_msi_domain,
+                                      msinr - 16);
+               handle_IRQ(irq, regs);
+       }
+}
+#else
+static void armada_370_xp_handle_msi_irq(struct pt_regs *r) {}
+#endif
+
 static asmlinkage void __exception_irq_entry
 armada_370_xp_handle_irq(struct pt_regs *regs)
 {
@@ -372,31 +400,9 @@ armada_370_xp_handle_irq(struct pt_regs *regs)
                        continue;
                }
 
-#ifdef CONFIG_PCI_MSI
                /* MSI handling */
-               if (irqnr == 1) {
-                       u32 msimask, msinr;
-
-                       msimask = readl_relaxed(per_cpu_int_base +
-                                               ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
-                               & PCI_MSI_DOORBELL_MASK;
-
-                       writel(~msimask, per_cpu_int_base +
-                              ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
-
-                       for (msinr = PCI_MSI_DOORBELL_START;
-                            msinr < PCI_MSI_DOORBELL_END; msinr++) {
-                               int irq;
-
-                               if (!(msimask & BIT(msinr)))
-                                       continue;
-
-                               irq = irq_find_mapping(armada_370_xp_msi_domain,
-                                                      msinr - 16);
-                               handle_IRQ(irq, regs);
-                       }
-               }
-#endif
+               if (irqnr == 1)
+                       armada_370_xp_handle_msi_irq(regs);
 
 #ifdef CONFIG_SMP
                /* IPI Handling */