1 files changed, 72 insertions, 0 deletions
diff --git a/arch/arm/plat-versatile/fpga-irq.c b/arch/arm/plat-versatile/fpga-irq.c
new file mode 100644
index 0000000..f0cc8e1
--- /dev/null
+++ b/arch/arm/plat-versatile/fpga-irq.c
@@ -0,0 +1,72 @@
+/*
+ *  Support for Versatile FPGA-based IRQ controllers
+ */
+#include <linux/irq.h>
+#include <linux/io.h>
+
+#include <asm/mach/irq.h>
+#include <plat/fpga-irq.h>
+
+#define IRQ_STATUS		0x00
+#define IRQ_RAW_STATUS		0x04
+#define IRQ_ENABLE_SET		0x08
+#define IRQ_ENABLE_CLEAR	0x0c
+
+static void fpga_irq_mask(struct irq_data *d)
+{
+	struct fpga_irq_data *f = irq_data_get_irq_chip_data(d);
+	u32 mask = 1 << (d->irq - f->irq_start);
+
+	writel(mask, f->base + IRQ_ENABLE_CLEAR);
+}
+
+static void fpga_irq_unmask(struct irq_data *d)
+{
+	struct fpga_irq_data *f = irq_data_get_irq_chip_data(d);
+	u32 mask = 1 << (d->irq - f->irq_start);
+
+	writel(mask, f->base + IRQ_ENABLE_SET);
+}
+
+static void fpga_irq_handle(unsigned int irq, struct irq_desc *desc)
+{
+	struct fpga_irq_data *f = irq_desc_get_handler_data(desc);
+	u32 status = readl(f->base + IRQ_STATUS);
+
+	if (status == 0) {
+		do_bad_IRQ(irq, desc);
+		return;
+	}
+
+	do {
+		irq = ffs(status) - 1;
+		status &= ~(1 << irq);
+
+		generic_handle_irq(irq + f->irq_start);
+	} while (status);
+}
+
+void __init fpga_irq_init(int parent_irq, u32 valid, struct fpga_irq_data *f)
+{
+	unsigned int i;
+
+	f->chip.irq_ack = fpga_irq_mask;
+	f->chip.irq_mask = fpga_irq_mask;
+	f->chip.irq_unmask = fpga_irq_unmask;
+
+	if (parent_irq != -1) {
+		irq_set_handler_data(parent_irq, f);
+		irq_set_chained_handler(parent_irq, fpga_irq_handle);
+	}
+
+	for (i = 0; i < 32; i++) {
+		if (valid & (1 << i)) {
+			unsigned int irq = f->irq_start + i;
+
+			irq_set_chip_data(irq, f);
+			irq_set_chip_and_handler(irq, &f->chip,
+						 handle_level_irq);
+			set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+		}
+	}
+}