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>

1 files changed, 30 insertions, 24 deletions

diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c
index 540956465ed2..2ba5761a638e 100644
--- 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 */