1 files changed, 148 insertions, 0 deletions

diff --git a/arch/sh/boards/harp/irq.c b/arch/sh/boards/harp/irq.c
new file mode 100644
index 000000000000..acd58489970f
--- /dev/null
+++ b/arch/sh/boards/harp/irq.c
@@ -0,0 +1,148 @@
+/* 
+ * Copyright (C) 2000 David J. Mckay (david.mckay@st.com)
+ *
+ * May be copied or modified under the terms of the GNU General Public
+ * License.  See linux/COPYING for more information.                            
+ *
+ * Looks after interrupts on the HARP board.
+ *
+ * Bases on the IPR irq system
+ */
+
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/harp/harp.h>
+
+
+#define NUM_EXTERNAL_IRQS 16
+
+// Early versions of the STB1 Overdrive required this nasty frig
+//#define INVERT_INTMASK_WRITES
+
+static void enable_harp_irq(unsigned int irq);
+static void disable_harp_irq(unsigned int irq);
+
+/* shutdown is same as "disable" */
+#define shutdown_harp_irq disable_harp_irq
+
+static void mask_and_ack_harp(unsigned int);
+static void end_harp_irq(unsigned int irq);
+
+static unsigned int startup_harp_irq(unsigned int irq)
+{
+        enable_harp_irq(irq);
+        return 0;               /* never anything pending */
+}
+
+static struct hw_interrupt_type harp_irq_type = {
+        "Harp-IRQ",
+        startup_harp_irq,
+        shutdown_harp_irq,
+        enable_harp_irq,
+        disable_harp_irq,
+        mask_and_ack_harp,
+        end_harp_irq
+};
+
+static void disable_harp_irq(unsigned int irq)
+{
+        unsigned val, flags;
+        unsigned maskReg;
+        unsigned mask;
+        int pri;
+
+        if (irq < 0 || irq >= NUM_EXTERNAL_IRQS)
+                return;
+
+        pri = 15 - irq;
+
+        if (pri < 8) {
+                maskReg = EPLD_INTMASK0;
+        } else {
+                maskReg = EPLD_INTMASK1;
+                pri -= 8;
+        }
+
+        local_irq_save(flags);
+        mask = ctrl_inl(maskReg);
+        mask &= (~(1 << pri));
+#if defined(INVERT_INTMASK_WRITES)
+        mask ^= 0xff;
+#endif
+        ctrl_outl(mask, maskReg);
+        local_irq_restore(flags);
+}
+
+static void enable_harp_irq(unsigned int irq)
+{
+        unsigned flags;
+        unsigned maskReg;
+        unsigned mask;
+        int pri;
+
+        if (irq < 0 || irq >= NUM_EXTERNAL_IRQS)
+                return;
+
+        pri = 15 - irq;
+
+        if (pri < 8) {
+                maskReg = EPLD_INTMASK0;
+        } else {
+                maskReg = EPLD_INTMASK1;
+                pri -= 8;
+        }
+
+        local_irq_save(flags);
+        mask = ctrl_inl(maskReg);
+
+
+        mask |= (1 << pri);
+
+#if defined(INVERT_INTMASK_WRITES)
+        mask ^= 0xff;
+#endif
+        ctrl_outl(mask, maskReg);
+
+        local_irq_restore(flags);
+}
+
+/* This functions sets the desired irq handler to be an overdrive type */
+static void __init make_harp_irq(unsigned int irq)
+{
+        disable_irq_nosync(irq);
+        irq_desc[irq].handler = &harp_irq_type;
+        disable_harp_irq(irq);
+}
+
+static void mask_and_ack_harp(unsigned int irq)
+{
+        disable_harp_irq(irq);
+}
+
+static void end_harp_irq(unsigned int irq)
+{
+        enable_harp_irq(irq);
+}
+
+void __init init_harp_irq(void)
+{
+        int i;
+
+#if !defined(INVERT_INTMASK_WRITES)
+        // On the harp these are set to enable an interrupt
+        ctrl_outl(0x00, EPLD_INTMASK0);
+        ctrl_outl(0x00, EPLD_INTMASK1);
+#else
+        // On the Overdrive the data is inverted before being stored in the reg
+        ctrl_outl(0xff, EPLD_INTMASK0);
+        ctrl_outl(0xff, EPLD_INTMASK1);
+#endif
+
+        for (i = 0; i < NUM_EXTERNAL_IRQS; i++) {
+                make_harp_irq(i);
+        }
+}