patch-2.0.21-2.1.0 linux/arch/m68k/amiga/cia.c

• Lines: 191
• Date: Wed Sep 25 10:47:38 1996
• Orig file: lx2.0/v2.0.21/linux/arch/m68k/amiga/cia.c
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file lx2.0/v2.0.21/linux/arch/m68k/amiga/cia.c linux/arch/m68k/amiga/cia.c
@@ -0,0 +1,190 @@
+/*
+ *  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 <asm/irq.h>
+#include <asm/amigahw.h>
+#include <asm/amigaints.h>
+
+struct ciabase {
+	volatile struct CIA *cia;
+	u_char icr_mask, icr_data;
+	u_short int_mask;
+	int handler_irq, cia_irq, server_irq;
+	char *name;
+	struct irq_server server;
+	irq_handler_t irq_list[CIA_IRQS];
+} ciaa_base = {
+	&ciaa, 0, 0, IF_PORTS,
+	IRQ2, IRQ_AMIGA_CIAA,
+	IRQ_IDX(IRQ_AMIGA_PORTS),
+	"CIAA handler", {0, 0}
+}, ciab_base = {
+	&ciab, 0, 0, IF_EXTER,
+	IRQ6, IRQ_AMIGA_CIAB,
+	IRQ_IDX(IRQ_AMIGA_EXTER),
+	"CIAB handler", {0, 0}
+};
+
+/*
+ *  Cause or clear CIA interrupts, return old interrupt status.
+ */
+
+unsigned char cia_set_irq(struct ciabase *base, unsigned char mask)
+{
+	u_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)
+{
+	u_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;
+ 	}
+	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,
+                    void (*handler)(int, void *, struct pt_regs *),
+                    unsigned long flags, const char *devname, void *dev_id)
+{
+	u_char mask;
+
+	if (!(base->irq_list[irq].flags & IRQ_FLG_STD)) {
+		if (base->irq_list[irq].flags & IRQ_FLG_LOCK) {
+			printk("%s: IRQ %ld from %s is not replaceable\n",
+			       __FUNCTION__, IRQ_IDX(base->cia_irq + irq),
+			       base->irq_list[irq].devname);
+			return -EBUSY;
+		}
+		if (flags & IRQ_FLG_REPLACE) {
+			printk("%s: %s can't replace IRQ %ld from %s\n", __FUNCTION__,
+			       devname, IRQ_IDX(base->cia_irq + irq),
+			       base->irq_list[irq].devname);
+			return -EBUSY;
+		}
+	}
+	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 %ld from %s\n",
+		       __FUNCTION__, IRQ_IDX(base->cia_irq + irq),
+		       base->irq_list[irq].devname);
+
+	base->irq_list[irq].handler = NULL;
+	base->irq_list[irq].flags   = IRQ_FLG_STD;
+
+	cia_able_irq(base, 1 << irq);
+}
+
+static void 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 + IRQ_IDX(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.interrupts[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, &base->server);
+}
+
+void 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   = IRQ_FLG_STD;
+	}
+
+	/* 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, IRQ_FLG_LOCK, base->name, base);
+
+	custom.intena = IF_SETCLR | base->int_mask;
+}
+
+int cia_get_irq_list(struct ciabase *base, char *buf)
+{
+	int i, j, len = 0;
+
+	j = IRQ_IDX(base->cia_irq);
+	for (i = 0; i < CIA_IRQS; i++) {
+		if (!(base->irq_list[i].flags & IRQ_FLG_STD)) {
+			len += sprintf(buf+len, "cia  %2d: %10d ", j + i,
+			               kstat.interrupts[SYS_IRQS + j + i]);
+			if (base->irq_list[i].flags & IRQ_FLG_LOCK)
+				len += sprintf(buf+len, "L ");
+			else
+				len += sprintf(buf+len, "  ");
+			len += sprintf(buf+len, "%s\n", base->irq_list[i].devname);
+		}
+	}
+	return len;
+}