1 files changed, 170 insertions, 28 deletions

diff --git a/arch/powerpc/sysdev/xilinx_intc.c b/arch/powerpc/sysdev/xilinx_intc.c
index a22e1a2df1a..3ee1fd37bbf 100644
--- a/arch/powerpc/sysdev/xilinx_intc.c
+++ b/arch/powerpc/sysdev/xilinx_intc.c
@@ -25,6 +25,7 @@
 #include <linux/of.h>
 #include <asm/io.h>
 #include <asm/processor.h>
+#include <asm/i8259.h>
 #include <asm/irq.h>
 
 /*
@@ -41,8 +42,32 @@
 
 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 +77,54 @@ 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);
@@ -68,47 +132,74 @@ 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
 xilinx_intc_init(struct device_node *np)
 {
 	struct irq_host * irq;
-	struct resource res;
 	void * regs;
-	int rc;
 
 	/* Find and map the intc registers */
-	rc = of_address_to_resource(np, 0, &res);
-	if (rc) {
-		printk(KERN_ERR __FILE__ ": of_address_to_resource() failed\n");
+	regs = of_iomap(np, 0);
+	if (!regs) {
+		pr_err("xilinx_intc: could not map registers\n");
 		return NULL;
 	}
-	regs = ioremap(res.start, 32);
-
-	printk(KERN_INFO "Xilinx intc at 0x%08llx mapped to 0x%p\n",
-		(unsigned long long) res.start, regs);
 
 	/* Setup interrupt controller */
 	out_be32(regs + XINTC_IER, 0); /* disable all irqs */
@@ -116,10 +207,12 @@ 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;
+
 	return irq;
 }
 
@@ -130,23 +223,70 @@ int xilinx_intc_get_irq(void)
 	return irq_linear_revmap(master_irqhost, in_be32(regs + XINTC_IVR));
 }
 
+#if defined(CONFIG_PPC_I8259)
+/*
+ * Support code for cascading to 8259 interrupt controllers
+ */
+static void xilinx_i8259_cascade(unsigned int irq, struct irq_desc *desc)
+{
+	unsigned int cascade_irq = i8259_irq();
+	if (cascade_irq)
+		generic_handle_irq(cascade_irq);
+
+	/* Let xilinx_intc end the interrupt */
+	desc->chip->ack(irq);
+	desc->chip->unmask(irq);
+}
+
+static void __init xilinx_i8259_setup_cascade(void)
+{
+	struct device_node *cascade_node;
+	int cascade_irq;
+
+	/* Initialize i8259 controller */
+	cascade_node = of_find_compatible_node(NULL, NULL, "chrp,iic");
+	if (!cascade_node)
+		return;
+
+	cascade_irq = irq_of_parse_and_map(cascade_node, 0);
+	if (!cascade_irq) {
+		pr_err("virtex_ml510: Failed to map cascade interrupt\n");
+		goto out;
+	}
+
+	i8259_init(cascade_node, 0);
+	set_irq_chained_handler(cascade_irq, xilinx_i8259_cascade);
+
+	/* Program irq 7 (usb/audio), 14/15 (ide) to level sensitive */
+	/* This looks like a dirty hack to me --gcl */
+	outb(0xc0, 0x4d0);
+	outb(0xc0, 0x4d1);
+
+ out:
+	of_node_put(cascade_node);
+}
+#else
+static inline void xilinx_i8259_setup_cascade(void) { return; }
+#endif /* defined(CONFIG_PPC_I8259) */
+
+static struct of_device_id xilinx_intc_match[] __initconst = {
+	{ .compatible = "xlnx,opb-intc-1.00.c", },
+	{ .compatible = "xlnx,xps-intc-1.00.a", },
+	{}
+};
+
+/*
+ * Initialize master Xilinx interrupt controller
+ */
 void __init xilinx_intc_init_tree(void)
 {
 	struct device_node *np;
 
 	/* find top level interrupt controller */
-	for_each_compatible_node(np, NULL, "xlnx,opb-intc-1.00.c") {
+	for_each_matching_node(np, xilinx_intc_match) {
 		if (!of_get_property(np, "interrupts", NULL))
 			break;
 	}
-	if (!np) {
-		for_each_compatible_node(np, NULL, "xlnx,xps-intc-1.00.a") {
-			if (!of_get_property(np, "interrupts", NULL))
-				break;
-		}
-	}
-
-	/* xilinx interrupt controller needs to be top level */
 	BUG_ON(!np);
 
 	master_irqhost = xilinx_intc_init(np);
@@ -154,4 +294,6 @@ void __init xilinx_intc_init_tree(void)
 
 	irq_set_default_host(master_irqhost);
 	of_node_put(np);
+
+	xilinx_i8259_setup_cascade();
 }