1 files changed, 168 insertions, 0 deletions

diff --git a/arch/arm/mach-footbridge/isa-irq.c b/arch/arm/mach-footbridge/isa-irq.c
new file mode 100644
index 000000000000..b21016070ea3
--- /dev/null
+++ b/arch/arm/mach-footbridge/isa-irq.c
@@ -0,0 +1,168 @@
+/*
+ *  linux/arch/arm/mach-footbridge/irq.c
+ *
+ *  Copyright (C) 1996-2000 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  Changelog:
+ *   22-Aug-1998 RMK    Restructured IRQ routines
+ *   03-Sep-1998 PJB    Merged CATS support
+ *   20-Jan-1998 RMK    Started merge of EBSA286, CATS and NetWinder
+ *   26-Jan-1999 PJB    Don't use IACK on CATS
+ *   16-Mar-1999 RMK    Added autodetect of ISA PICs
+ */
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/init.h>
+
+#include <asm/mach/irq.h>
+
+#include <asm/hardware.h>
+#include <asm/hardware/dec21285.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/mach-types.h>
+
+static void isa_mask_pic_lo_irq(unsigned int irq)
+{
+        unsigned int mask = 1 << (irq & 7);
+
+        outb(inb(PIC_MASK_LO) | mask, PIC_MASK_LO);
+}
+
+static void isa_ack_pic_lo_irq(unsigned int irq)
+{
+        unsigned int mask = 1 << (irq & 7);
+
+        outb(inb(PIC_MASK_LO) | mask, PIC_MASK_LO);
+        outb(0x20, PIC_LO);
+}
+
+static void isa_unmask_pic_lo_irq(unsigned int irq)
+{
+        unsigned int mask = 1 << (irq & 7);
+
+        outb(inb(PIC_MASK_LO) & ~mask, PIC_MASK_LO);
+}
+
+static struct irqchip isa_lo_chip = {
+        .ack    = isa_ack_pic_lo_irq,
+        .mask   = isa_mask_pic_lo_irq,
+        .unmask = isa_unmask_pic_lo_irq,
+};
+
+static void isa_mask_pic_hi_irq(unsigned int irq)
+{
+        unsigned int mask = 1 << (irq & 7);
+
+        outb(inb(PIC_MASK_HI) | mask, PIC_MASK_HI);
+}
+
+static void isa_ack_pic_hi_irq(unsigned int irq)
+{
+        unsigned int mask = 1 << (irq & 7);
+
+        outb(inb(PIC_MASK_HI) | mask, PIC_MASK_HI);
+        outb(0x62, PIC_LO);
+        outb(0x20, PIC_HI);
+}
+
+static void isa_unmask_pic_hi_irq(unsigned int irq)
+{
+        unsigned int mask = 1 << (irq & 7);
+
+        outb(inb(PIC_MASK_HI) & ~mask, PIC_MASK_HI);
+}
+
+static struct irqchip isa_hi_chip = {
+        .ack    = isa_ack_pic_hi_irq,
+        .mask   = isa_mask_pic_hi_irq,
+        .unmask = isa_unmask_pic_hi_irq,
+};
+
+static void
+isa_irq_handler(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
+{
+        unsigned int isa_irq = *(unsigned char *)PCIIACK_BASE;
+
+        if (isa_irq < _ISA_IRQ(0) || isa_irq >= _ISA_IRQ(16)) {
+                do_bad_IRQ(isa_irq, desc, regs);
+                return;
+        }
+
+        desc = irq_desc + isa_irq;
+        desc->handle(isa_irq, desc, regs);
+}
+
+static struct irqaction irq_cascade = { .handler = no_action, .name = "cascade", };
+static struct resource pic1_resource = { "pic1", 0x20, 0x3f };
+static struct resource pic2_resource = { "pic2", 0xa0, 0xbf };
+
+void __init isa_init_irq(unsigned int host_irq)
+{
+        unsigned int irq;
+
+        /*
+         * Setup, and then probe for an ISA PIC
+         * If the PIC is not there, then we
+         * ignore the PIC.
+         */
+        outb(0x11, PIC_LO);
+        outb(_ISA_IRQ(0), PIC_MASK_LO); /* IRQ number           */
+        outb(0x04, PIC_MASK_LO);        /* Slave on Ch2         */
+        outb(0x01, PIC_MASK_LO);        /* x86                  */
+        outb(0xf5, PIC_MASK_LO);        /* pattern: 11110101    */
+
+        outb(0x11, PIC_HI);
+        outb(_ISA_IRQ(8), PIC_MASK_HI); /* IRQ number           */
+        outb(0x02, PIC_MASK_HI);        /* Slave on Ch1         */
+        outb(0x01, PIC_MASK_HI);        /* x86                  */
+        outb(0xfa, PIC_MASK_HI);        /* pattern: 11111010    */
+
+        outb(0x0b, PIC_LO);
+        outb(0x0b, PIC_HI);
+
+        if (inb(PIC_MASK_LO) == 0xf5 && inb(PIC_MASK_HI) == 0xfa) {
+                outb(0xff, PIC_MASK_LO);/* mask all IRQs        */
+                outb(0xff, PIC_MASK_HI);/* mask all IRQs        */
+        } else {
+                printk(KERN_INFO "IRQ: ISA PIC not found\n");
+                host_irq = (unsigned int)-1;
+        }
+
+        if (host_irq != (unsigned int)-1) {
+                for (irq = _ISA_IRQ(0); irq < _ISA_IRQ(8); irq++) {
+                        set_irq_chip(irq, &isa_lo_chip);
+                        set_irq_handler(irq, do_level_IRQ);
+                        set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+                }
+
+                for (irq = _ISA_IRQ(8); irq < _ISA_IRQ(16); irq++) {
+                        set_irq_chip(irq, &isa_hi_chip);
+                        set_irq_handler(irq, do_level_IRQ);
+                        set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+                }
+
+                request_resource(&ioport_resource, &pic1_resource);
+                request_resource(&ioport_resource, &pic2_resource);
+                setup_irq(IRQ_ISA_CASCADE, &irq_cascade);
+
+                set_irq_chained_handler(host_irq, isa_irq_handler);
+
+                /*
+                 * On the NetWinder, don't automatically
+                 * enable ISA IRQ11 when it is requested.
+                 * There appears to be a missing pull-up
+                 * resistor on this line.
+                 */
+                if (machine_is_netwinder())
+                        set_irq_flags(_ISA_IRQ(11), IRQF_VALID |
+                                      IRQF_PROBE | IRQF_NOAUTOEN);
+        }
+}
+
+