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-rw-r--r--arch/m68k/amiga/cia.c180
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;
+}