1 files changed, 105 insertions, 0 deletions
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
new file mode 100644
index 000000000000..480b6a5fef3a
--- /dev/null
+++ b/arch/s390/kernel/irq.c
@@ -0,0 +1,105 @@
+/*
+ *  arch/s390/kernel/irq.c
+ *
+ *  S390 version
+ *    Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
+ *
+ * This file contains interrupt related functions.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/kernel_stat.h>
+#include <linux/interrupt.h>
+#include <linux/seq_file.h>
+#include <linux/cpu.h>
+
+/*
+ * show_interrupts is needed by /proc/interrupts.
+ */
+int show_interrupts(struct seq_file *p, void *v)
+{
+	static const char *intrclass_names[] = { "EXT", "I/O", };
+	int i = *(loff_t *) v, j;
+
+	if (i == 0) {
+		seq_puts(p, "           ");
+		for_each_online_cpu(j)
+			seq_printf(p, "CPU%d       ",j);
+		seq_putc(p, '\n');
+	}
+
+	if (i < NR_IRQS) {
+		seq_printf(p, "%s: ", intrclass_names[i]);
+#ifndef CONFIG_SMP
+		seq_printf(p, "%10u ", kstat_irqs(i));
+#else
+		for_each_online_cpu(j)
+			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+#endif
+                seq_putc(p, '\n');
+
+        }
+
+        return 0;
+}
+
+/*
+ * For compatibilty only. S/390 specific setup of interrupts et al. is done
+ * much later in init_channel_subsystem().
+ */
+void __init
+init_IRQ(void)
+{
+	/* nothing... */
+}
+
+/*
+ * Switch to the asynchronous interrupt stack for softirq execution.
+ */
+extern void __do_softirq(void);
+
+asmlinkage void do_softirq(void)
+{
+	unsigned long flags, old, new;
+
+	if (in_interrupt())
+		return;
+
+	local_irq_save(flags);
+
+	account_system_vtime(current);
+
+	local_bh_disable();
+
+	if (local_softirq_pending()) {
+		/* Get current stack pointer. */
+		asm volatile("la %0,0(15)" : "=a" (old));
+		/* Check against async. stack address range. */
+		new = S390_lowcore.async_stack;
+		if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) {
+			/* Need to switch to the async. stack. */
+			new -= STACK_FRAME_OVERHEAD;
+			((struct stack_frame *) new)->back_chain = old;
+
+			asm volatile("   la    15,0(%0)\n"
+				     "   basr  14,%2\n"
+				     "   la    15,0(%1)\n"
+				     : : "a" (new), "a" (old),
+				         "a" (__do_softirq)
+				     : "0", "1", "2", "3", "4", "5", "14",
+				       "cc", "memory" );
+		} else
+			/* We are already on the async stack. */
+			__do_softirq();
+	}
+
+	account_system_vtime(current);
+
+	__local_bh_enable();
+
+	local_irq_restore(flags);
+}
+
+EXPORT_SYMBOL(do_softirq);