1 files changed, 107 insertions, 10 deletions

diff --git a/arch/powerpc/sysdev/xilinx_intc.c b/arch/powerpc/sysdev/xilinx_intc.c
index a22e1a2df1af..c658b413c9b4 100644
--- a/arch/powerpc/sysdev/xilinx_intc.c
+++ b/arch/powerpc/sysdev/xilinx_intc.c
@@ -41,8 +41,32 @@
 
 static struct irq_host *master_irqhost;
 
+#define XILINX_INTC_MAXIRQS	(32)
+
+/* The following table allows the interrupt type, edge or level,
+ * to be cached after being read from the device tree until the interrupt
+ * is mapped
+ */
+static int xilinx_intc_typetable[XILINX_INTC_MAXIRQS];
+
+/* Map the interrupt type from the device tree to the interrupt types
+ * used by the interrupt subsystem
+ */
+static unsigned char xilinx_intc_map_senses[] = {
+	IRQ_TYPE_EDGE_RISING,
+	IRQ_TYPE_EDGE_FALLING,
+	IRQ_TYPE_LEVEL_HIGH,
+	IRQ_TYPE_LEVEL_LOW,
+};
+
 /*
- * IRQ Chip operations
+ * The interrupt controller is setup such that it doesn't work well with
+ * the level interrupt handler in the kernel because the handler acks the
+ * interrupt before calling the application interrupt handler. To deal with
+ * that, we use 2 different irq chips so that different functions can be
+ * used for level and edge type interrupts.
+ *
+ * IRQ Chip common (across level and edge) operations
  */
 static void xilinx_intc_mask(unsigned int virq)
 {
@@ -52,15 +76,54 @@ static void xilinx_intc_mask(unsigned int virq)
 	out_be32(regs + XINTC_CIE, 1 << irq);
 }
 
-static void xilinx_intc_unmask(unsigned int virq)
+static int xilinx_intc_set_type(unsigned int virq, unsigned int flow_type)
+{
+	struct irq_desc *desc = get_irq_desc(virq);
+
+	desc->status &= ~(IRQ_TYPE_SENSE_MASK | IRQ_LEVEL);
+	desc->status |= flow_type & IRQ_TYPE_SENSE_MASK;
+	if (flow_type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
+		desc->status |= IRQ_LEVEL;
+	return 0;
+}
+
+/*
+ * IRQ Chip level operations
+ */
+static void xilinx_intc_level_unmask(unsigned int virq)
 {
 	int irq = virq_to_hw(virq);
 	void * regs = get_irq_chip_data(virq);
 	pr_debug("unmask: %d\n", irq);
 	out_be32(regs + XINTC_SIE, 1 << irq);
+
+	/* ack level irqs because they can't be acked during
+	 * ack function since the handle_level_irq function
+	 * acks the irq before calling the inerrupt handler
+	 */
+	out_be32(regs + XINTC_IAR, 1 << irq);
 }
 
-static void xilinx_intc_ack(unsigned int virq)
+static struct irq_chip xilinx_intc_level_irqchip = {
+	.typename = "Xilinx Level INTC",
+	.mask = xilinx_intc_mask,
+	.mask_ack = xilinx_intc_mask,
+	.unmask = xilinx_intc_level_unmask,
+	.set_type = xilinx_intc_set_type,
+};
+
+/*
+ * IRQ Chip edge operations
+ */
+static void xilinx_intc_edge_unmask(unsigned int virq)
+{
+	int irq = virq_to_hw(virq);
+	void *regs = get_irq_chip_data(virq);
+	pr_debug("unmask: %d\n", irq);
+	out_be32(regs + XINTC_SIE, 1 << irq);
+}
+
+static void xilinx_intc_edge_ack(unsigned int virq)
 {
 	int irq = virq_to_hw(virq);
 	void * regs = get_irq_chip_data(virq);
@@ -68,27 +131,60 @@ static void xilinx_intc_ack(unsigned int virq)
 	out_be32(regs + XINTC_IAR, 1 << irq);
 }
 
-static struct irq_chip xilinx_intc_irqchip = {
-	.typename = "Xilinx INTC",
+static struct irq_chip xilinx_intc_edge_irqchip = {
+	.typename = "Xilinx Edge  INTC",
 	.mask = xilinx_intc_mask,
-	.unmask = xilinx_intc_unmask,
-	.ack = xilinx_intc_ack,
+	.unmask = xilinx_intc_edge_unmask,
+	.ack = xilinx_intc_edge_ack,
+	.set_type = xilinx_intc_set_type,
 };
 
 /*
  * IRQ Host operations
  */
+
+/**
+ * xilinx_intc_xlate - translate virq# from device tree interrupts property
+ */
+static int xilinx_intc_xlate(struct irq_host *h, struct device_node *ct,
+				u32 *intspec, unsigned int intsize,
+				irq_hw_number_t *out_hwirq,
+				unsigned int *out_flags)
+{
+	if ((intsize < 2) || (intspec[0] >= XILINX_INTC_MAXIRQS))
+		return -EINVAL;
+
+	/* keep a copy of the interrupt type til the interrupt is mapped
+	 */
+	xilinx_intc_typetable[intspec[0]] = xilinx_intc_map_senses[intspec[1]];
+
+	/* Xilinx uses 2 interrupt entries, the 1st being the h/w
+	 * interrupt number, the 2nd being the interrupt type, edge or level
+	 */
+	*out_hwirq = intspec[0];
+	*out_flags = xilinx_intc_map_senses[intspec[1]];
+
+	return 0;
+}
 static int xilinx_intc_map(struct irq_host *h, unsigned int virq,
 				  irq_hw_number_t irq)
 {
 	set_irq_chip_data(virq, h->host_data);
-	set_irq_chip_and_handler(virq, &xilinx_intc_irqchip, handle_level_irq);
-	set_irq_type(virq, IRQ_TYPE_NONE);
+
+	if (xilinx_intc_typetable[irq] == IRQ_TYPE_LEVEL_HIGH ||
+	    xilinx_intc_typetable[irq] == IRQ_TYPE_LEVEL_LOW) {
+		set_irq_chip_and_handler(virq, &xilinx_intc_level_irqchip,
+			handle_level_irq);
+	} else {
+		set_irq_chip_and_handler(virq, &xilinx_intc_edge_irqchip,
+			handle_edge_irq);
+	}
 	return 0;
 }
 
 static struct irq_host_ops xilinx_intc_ops = {
 	.map = xilinx_intc_map,
+	.xlate = xilinx_intc_xlate,
 };
 
 struct irq_host * __init
@@ -116,7 +212,8 @@ xilinx_intc_init(struct device_node *np)
 	out_be32(regs + XINTC_MER, 0x3UL); /* Turn on the Master Enable. */
 
 	/* Allocate and initialize an irq_host structure. */
-	irq = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, 32, &xilinx_intc_ops, -1);
+	irq = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, XILINX_INTC_MAXIRQS,
+			     &xilinx_intc_ops, -1);
 	if (!irq)
 		panic(__FILE__ ": Cannot allocate IRQ host\n");
 	irq->host_data = regs;