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Diffstat (limited to 'arch/mn10300/unit-asb2364/irq-fpga.c')
-rw-r--r--arch/mn10300/unit-asb2364/irq-fpga.c96
1 files changed, 96 insertions, 0 deletions
diff --git a/arch/mn10300/unit-asb2364/irq-fpga.c b/arch/mn10300/unit-asb2364/irq-fpga.c
new file mode 100644
index 000000000000..fcf29754e4d1
--- /dev/null
+++ b/arch/mn10300/unit-asb2364/irq-fpga.c
@@ -0,0 +1,96 @@
+/* ASB2364 FPGA interrupt multiplexing
+ *
+ * Copyright (C) 2010 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <unit/fpga-regs.h>
+
+/*
+ * FPGA PIC operations
+ */
+static void asb2364_fpga_mask(unsigned int irq)
+{
+ ASB2364_FPGA_REG_MASK(irq - NR_CPU_IRQS) = 0x0001;
+ SyncExBus();
+}
+
+static void asb2364_fpga_ack(unsigned int irq)
+{
+ ASB2364_FPGA_REG_IRQ(irq - NR_CPU_IRQS) = 0x0001;
+ SyncExBus();
+}
+
+static void asb2364_fpga_mask_ack(unsigned int irq)
+{
+ ASB2364_FPGA_REG_MASK(irq - NR_CPU_IRQS) = 0x0001;
+ SyncExBus();
+ ASB2364_FPGA_REG_IRQ(irq - NR_CPU_IRQS) = 0x0001;
+ SyncExBus();
+}
+
+static void asb2364_fpga_unmask(unsigned int irq)
+{
+ ASB2364_FPGA_REG_MASK(irq - NR_CPU_IRQS) = 0x0000;
+ SyncExBus();
+}
+
+static struct irq_chip asb2364_fpga_pic = {
+ .name = "fpga",
+ .ack = asb2364_fpga_ack,
+ .mask = asb2364_fpga_mask,
+ .mask_ack = asb2364_fpga_mask_ack,
+ .unmask = asb2364_fpga_unmask,
+};
+
+/*
+ * FPGA PIC interrupt handler
+ */
+static irqreturn_t fpga_interrupt(int irq, void *_mask)
+{
+ if ((ASB2364_FPGA_REG_IRQ_LAN & 0x0001) != 0x0001)
+ generic_handle_irq(FPGA_LAN_IRQ);
+ if ((ASB2364_FPGA_REG_IRQ_UART & 0x0001) != 0x0001)
+ generic_handle_irq(FPGA_UART_IRQ);
+ if ((ASB2364_FPGA_REG_IRQ_I2C & 0x0001) != 0x0001)
+ generic_handle_irq(FPGA_I2C_IRQ);
+ if ((ASB2364_FPGA_REG_IRQ_USB & 0x0001) != 0x0001)
+ generic_handle_irq(FPGA_USB_IRQ);
+ if ((ASB2364_FPGA_REG_IRQ_FPGA & 0x0001) != 0x0001)
+ generic_handle_irq(FPGA_FPGA_IRQ);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * Define an interrupt action for each FPGA PIC output
+ */
+static struct irqaction fpga_irq[] = {
+ [0] = {
+ .handler = fpga_interrupt,
+ .flags = IRQF_DISABLED | IRQF_SHARED,
+ .name = "fpga",
+ },
+};
+
+/*
+ * Initialise the FPGA's PIC
+ */
+void __init irq_fpga_init(void)
+{
+ int irq;
+
+ for (irq = NR_CPU_IRQS; irq < NR_IRQS; irq++)
+ set_irq_chip_and_handler(irq, &asb2364_fpga_pic, handle_level_irq);
+
+ /* the FPGA drives the XIRQ1 input on the CPU PIC */
+ setup_irq(XIRQ1, &fpga_irq[0]);
+}