1 files changed, 180 insertions, 0 deletions

diff --git a/arch/m68k/amiga/cia.c b/arch/m68k/amiga/cia.c
new file mode 100644
index 000000000000..7d55682615e3
--- /dev/null
+++ b/arch/m68k/amiga/cia.c
@@ -0,0 +1,180 @@
+/*
+ *  linux/arch/m68k/amiga/cia.c - CIA support
+ *
+ *  Copyright (C) 1996 Roman Zippel
+ *
+ *  The concept of some functions bases on the original Amiga OS function
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/kernel_stat.h>
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/interrupt.h>
+
+#include <asm/irq.h>
+#include <asm/amigahw.h>
+#include <asm/amigaints.h>
+
+struct ciabase {
+        volatile struct CIA *cia;
+        unsigned char icr_mask, icr_data;
+        unsigned short int_mask;
+        int handler_irq, cia_irq, server_irq;
+        char *name;
+        irq_handler_t irq_list[CIA_IRQS];
+} ciaa_base = {
+        .cia            = &ciaa,
+        .int_mask       = IF_PORTS,
+        .handler_irq    = IRQ_AMIGA_AUTO_2,
+        .cia_irq        = IRQ_AMIGA_CIAA,
+        .server_irq     = IRQ_AMIGA_PORTS,
+        .name           = "CIAA handler"
+}, ciab_base = {
+        .cia            = &ciab,
+        .int_mask       = IF_EXTER,
+        .handler_irq    = IRQ_AMIGA_AUTO_6,
+        .cia_irq        = IRQ_AMIGA_CIAB,
+        .server_irq     = IRQ_AMIGA_EXTER,
+        .name           = "CIAB handler"
+};
+
+/*
+ *  Cause or clear CIA interrupts, return old interrupt status.
+ */
+
+unsigned char cia_set_irq(struct ciabase *base, unsigned char mask)
+{
+        unsigned char old;
+
+        old = (base->icr_data |= base->cia->icr);
+        if (mask & CIA_ICR_SETCLR)
+                base->icr_data |= mask;
+        else
+                base->icr_data &= ~mask;
+        if (base->icr_data & base->icr_mask)
+                custom.intreq = IF_SETCLR | base->int_mask;
+        return old & base->icr_mask;
+}
+
+/*
+ *  Enable or disable CIA interrupts, return old interrupt mask,
+ *  interrupts will only be enabled if a handler exists
+ */
+
+unsigned char cia_able_irq(struct ciabase *base, unsigned char mask)
+{
+        unsigned char old, tmp;
+        int i;
+
+        old = base->icr_mask;
+        base->icr_data |= base->cia->icr;
+        base->cia->icr = mask;
+        if (mask & CIA_ICR_SETCLR)
+                base->icr_mask |= mask;
+        else
+                base->icr_mask &= ~mask;
+        base->icr_mask &= CIA_ICR_ALL;
+        for (i = 0, tmp = 1; i < CIA_IRQS; i++, tmp <<= 1) {
+                if ((tmp & base->icr_mask) && !base->irq_list[i].handler) {
+                        base->icr_mask &= ~tmp;
+                        base->cia->icr = tmp;
+                }
+        }
+        if (base->icr_data & base->icr_mask)
+                custom.intreq = IF_SETCLR | base->int_mask;
+        return old;
+}
+
+int cia_request_irq(struct ciabase *base, unsigned int irq,
+                    irqreturn_t (*handler)(int, void *, struct pt_regs *),
+                    unsigned long flags, const char *devname, void *dev_id)
+{
+        unsigned char mask;
+
+        base->irq_list[irq].handler = handler;
+        base->irq_list[irq].flags   = flags;
+        base->irq_list[irq].dev_id  = dev_id;
+        base->irq_list[irq].devname = devname;
+
+        /* enable the interrupt */
+        mask = 1 << irq;
+        cia_set_irq(base, mask);
+        cia_able_irq(base, CIA_ICR_SETCLR | mask);
+        return 0;
+}
+
+void cia_free_irq(struct ciabase *base, unsigned int irq, void *dev_id)
+{
+        if (base->irq_list[irq].dev_id != dev_id)
+                printk("%s: removing probably wrong IRQ %i from %s\n",
+                       __FUNCTION__, base->cia_irq + irq,
+                       base->irq_list[irq].devname);
+
+        base->irq_list[irq].handler = NULL;
+        base->irq_list[irq].flags   = 0;
+
+        cia_able_irq(base, 1 << irq);
+}
+
+static irqreturn_t cia_handler(int irq, void *dev_id, struct pt_regs *fp)
+{
+        struct ciabase *base = (struct ciabase *)dev_id;
+        int mach_irq, i;
+        unsigned char ints;
+
+        mach_irq = base->cia_irq;
+        irq = SYS_IRQS + mach_irq;
+        ints = cia_set_irq(base, CIA_ICR_ALL);
+        custom.intreq = base->int_mask;
+        for (i = 0; i < CIA_IRQS; i++, irq++, mach_irq++) {
+                if (ints & 1) {
+                        kstat_cpu(0).irqs[irq]++;
+                        base->irq_list[i].handler(mach_irq, base->irq_list[i].dev_id, fp);
+                }
+                ints >>= 1;
+        }
+        amiga_do_irq_list(base->server_irq, fp);
+        return IRQ_HANDLED;
+}
+
+void __init cia_init_IRQ(struct ciabase *base)
+{
+        int i;
+
+        /* init isr handlers */
+        for (i = 0; i < CIA_IRQS; i++) {
+                base->irq_list[i].handler = NULL;
+                base->irq_list[i].flags   = 0;
+        }
+
+        /* clear any pending interrupt and turn off all interrupts */
+        cia_set_irq(base, CIA_ICR_ALL);
+        cia_able_irq(base, CIA_ICR_ALL);
+
+        /* install CIA handler */
+        request_irq(base->handler_irq, cia_handler, 0, base->name, base);
+
+        custom.intena = IF_SETCLR | base->int_mask;
+}
+
+int cia_get_irq_list(struct ciabase *base, struct seq_file *p)
+{
+        int i, j;
+
+        j = base->cia_irq;
+        for (i = 0; i < CIA_IRQS; i++) {
+                seq_printf(p, "cia  %2d: %10d ", j + i,
+                               kstat_cpu(0).irqs[SYS_IRQS + j + i]);
+                seq_puts(p, "  ");
+                seq_printf(p, "%s\n", base->irq_list[i].devname);
+        }
+        return 0;
+}