v4.19.13 snapshot.
diff --git a/arch/sh/boards/mach-cayman/irq.c b/arch/sh/boards/mach-cayman/irq.c
new file mode 100644
index 0000000..724e8b7
--- /dev/null
+++ b/arch/sh/boards/mach-cayman/irq.c
@@ -0,0 +1,157 @@
+/*
+ * arch/sh/mach-cayman/irq.c - SH-5 Cayman Interrupt Support
+ *
+ * This file handles the board specific parts of the Cayman interrupt system
+ *
+ * Copyright (C) 2002 Stuart Menefy
+ *
+ * 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/io.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/signal.h>
+#include <cpu/irq.h>
+#include <asm/page.h>
+
+/* Setup for the SMSC FDC37C935 / LAN91C100FD */
+#define SMSC_IRQ         IRQ_IRL1
+
+/* Setup for PCI Bus 2, which transmits interrupts via the EPLD */
+#define PCI2_IRQ         IRQ_IRL3
+
+unsigned long epld_virt;
+
+#define EPLD_BASE        0x04002000
+#define EPLD_STATUS_BASE (epld_virt + 0x10)
+#define EPLD_MASK_BASE   (epld_virt + 0x20)
+
+/* Note the SMSC SuperIO chip and SMSC LAN chip interrupts are all muxed onto
+   the same SH-5 interrupt */
+
+static irqreturn_t cayman_interrupt_smsc(int irq, void *dev_id)
+{
+        printk(KERN_INFO "CAYMAN: spurious SMSC interrupt\n");
+	return IRQ_NONE;
+}
+
+static irqreturn_t cayman_interrupt_pci2(int irq, void *dev_id)
+{
+        printk(KERN_INFO "CAYMAN: spurious PCI interrupt, IRQ %d\n", irq);
+	return IRQ_NONE;
+}
+
+static struct irqaction cayman_action_smsc = {
+	.name		= "Cayman SMSC Mux",
+	.handler	= cayman_interrupt_smsc,
+};
+
+static struct irqaction cayman_action_pci2 = {
+	.name		= "Cayman PCI2 Mux",
+	.handler	= cayman_interrupt_pci2,
+};
+
+static void enable_cayman_irq(struct irq_data *data)
+{
+	unsigned int irq = data->irq;
+	unsigned long flags;
+	unsigned long mask;
+	unsigned int reg;
+	unsigned char bit;
+
+	irq -= START_EXT_IRQS;
+	reg = EPLD_MASK_BASE + ((irq / 8) << 2);
+	bit = 1<<(irq % 8);
+	local_irq_save(flags);
+	mask = __raw_readl(reg);
+	mask |= bit;
+	__raw_writel(mask, reg);
+	local_irq_restore(flags);
+}
+
+static void disable_cayman_irq(struct irq_data *data)
+{
+	unsigned int irq = data->irq;
+	unsigned long flags;
+	unsigned long mask;
+	unsigned int reg;
+	unsigned char bit;
+
+	irq -= START_EXT_IRQS;
+	reg = EPLD_MASK_BASE + ((irq / 8) << 2);
+	bit = 1<<(irq % 8);
+	local_irq_save(flags);
+	mask = __raw_readl(reg);
+	mask &= ~bit;
+	__raw_writel(mask, reg);
+	local_irq_restore(flags);
+}
+
+struct irq_chip cayman_irq_type = {
+	.name		= "Cayman-IRQ",
+	.irq_unmask	= enable_cayman_irq,
+	.irq_mask	= disable_cayman_irq,
+};
+
+int cayman_irq_demux(int evt)
+{
+	int irq = intc_evt_to_irq[evt];
+
+	if (irq == SMSC_IRQ) {
+		unsigned long status;
+		int i;
+
+		status = __raw_readl(EPLD_STATUS_BASE) &
+			 __raw_readl(EPLD_MASK_BASE) & 0xff;
+		if (status == 0) {
+			irq = -1;
+		} else {
+			for (i=0; i<8; i++) {
+				if (status & (1<<i))
+					break;
+			}
+			irq = START_EXT_IRQS + i;
+		}
+	}
+
+	if (irq == PCI2_IRQ) {
+		unsigned long status;
+		int i;
+
+		status = __raw_readl(EPLD_STATUS_BASE + 3 * sizeof(u32)) &
+			 __raw_readl(EPLD_MASK_BASE + 3 * sizeof(u32)) & 0xff;
+		if (status == 0) {
+			irq = -1;
+		} else {
+			for (i=0; i<8; i++) {
+				if (status & (1<<i))
+					break;
+			}
+			irq = START_EXT_IRQS + (3 * 8) + i;
+		}
+	}
+
+	return irq;
+}
+
+void init_cayman_irq(void)
+{
+	int i;
+
+	epld_virt = (unsigned long)ioremap_nocache(EPLD_BASE, 1024);
+	if (!epld_virt) {
+		printk(KERN_ERR "Cayman IRQ: Unable to remap EPLD\n");
+		return;
+	}
+
+	for (i = 0; i < NR_EXT_IRQS; i++) {
+		irq_set_chip_and_handler(START_EXT_IRQS + i,
+					 &cayman_irq_type, handle_level_irq);
+	}
+
+	/* Setup the SMSC interrupt */
+	setup_irq(SMSC_IRQ, &cayman_action_smsc);
+	setup_irq(PCI2_IRQ, &cayman_action_pci2);
+}