1 files changed, 137 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c/bast-irq.c b/arch/arm/mach-s3c/bast-irq.c
new file mode 100644
index 000000000000..d299f124e6dc
--- /dev/null
+++ b/arch/arm/mach-s3c/bast-irq.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright 2003-2005 Simtec Electronics
+//   Ben Dooks <ben@simtec.co.uk>
+//
+// http://www.simtec.co.uk/products/EB2410ITX/
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/device.h>
+#include <linux/io.h>
+
+#include <asm/irq.h>
+#include <asm/mach-types.h>
+#include <asm/mach/irq.h>
+
+#include "regs-irq.h"
+#include <mach/irqs.h>
+
+#include "bast.h"
+
+#define irqdbf(x...)
+#define irqdbf2(x...)
+
+/* handle PC104 ISA interrupts from the system CPLD */
+
+/* table of ISA irq nos to the relevant mask... zero means
+ * the irq is not implemented
+*/
+static const unsigned char bast_pc104_irqmasks[] = {
+	0,   /* 0 */
+	0,   /* 1 */
+	0,   /* 2 */
+	1,   /* 3 */
+	0,   /* 4 */
+	2,   /* 5 */
+	0,   /* 6 */
+	4,   /* 7 */
+	0,   /* 8 */
+	0,   /* 9 */
+	8,   /* 10 */
+	0,   /* 11 */
+	0,   /* 12 */
+	0,   /* 13 */
+	0,   /* 14 */
+	0,   /* 15 */
+};
+
+static const unsigned char bast_pc104_irqs[] = { 3, 5, 7, 10 };
+
+static void
+bast_pc104_mask(struct irq_data *data)
+{
+	unsigned long temp;
+
+	temp = __raw_readb(BAST_VA_PC104_IRQMASK);
+	temp &= ~bast_pc104_irqmasks[data->irq];
+	__raw_writeb(temp, BAST_VA_PC104_IRQMASK);
+}
+
+static void
+bast_pc104_maskack(struct irq_data *data)
+{
+	struct irq_desc *desc = irq_to_desc(BAST_IRQ_ISA);
+
+	bast_pc104_mask(data);
+	desc->irq_data.chip->irq_ack(&desc->irq_data);
+}
+
+static void
+bast_pc104_unmask(struct irq_data *data)
+{
+	unsigned long temp;
+
+	temp = __raw_readb(BAST_VA_PC104_IRQMASK);
+	temp |= bast_pc104_irqmasks[data->irq];
+	__raw_writeb(temp, BAST_VA_PC104_IRQMASK);
+}
+
+static struct irq_chip  bast_pc104_chip = {
+	.irq_mask	= bast_pc104_mask,
+	.irq_unmask	= bast_pc104_unmask,
+	.irq_ack	= bast_pc104_maskack
+};
+
+static void bast_irq_pc104_demux(struct irq_desc *desc)
+{
+	unsigned int stat;
+	unsigned int irqno;
+	int i;
+
+	stat = __raw_readb(BAST_VA_PC104_IRQREQ) & 0xf;
+
+	if (unlikely(stat == 0)) {
+		/* ack if we get an irq with nothing (ie, startup) */
+		desc->irq_data.chip->irq_ack(&desc->irq_data);
+	} else {
+		/* handle the IRQ */
+
+		for (i = 0; stat != 0; i++, stat >>= 1) {
+			if (stat & 1) {
+				irqno = bast_pc104_irqs[i];
+				generic_handle_irq(irqno);
+			}
+		}
+	}
+}
+
+static __init int bast_irq_init(void)
+{
+	unsigned int i;
+
+	if (machine_is_bast()) {
+		printk(KERN_INFO "BAST PC104 IRQ routing, Copyright 2005 Simtec Electronics\n");
+
+		/* zap all the IRQs */
+
+		__raw_writeb(0x0, BAST_VA_PC104_IRQMASK);
+
+		irq_set_chained_handler(BAST_IRQ_ISA, bast_irq_pc104_demux);
+
+		/* register our IRQs */
+
+		for (i = 0; i < 4; i++) {
+			unsigned int irqno = bast_pc104_irqs[i];
+
+			irq_set_chip_and_handler(irqno, &bast_pc104_chip,
+						 handle_level_irq);
+			irq_clear_status_flags(irqno, IRQ_NOREQUEST);
+		}
+	}
+
+	return 0;
+}
+
+arch_initcall(bast_irq_init);