[MIPS] Atlas, Malta, SEAD: Remove scroll from interrupt handler.

Aside of being handy for debugging this has never been a particularly
good idea but is now getting in the way of dyntick / tickless kernels
and general cleanups.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/mips-boards/generic/display.c b/arch/mips/mips-boards/generic/display.c
index 548dbe5..5d60005 100644
--- a/arch/mips/mips-boards/generic/display.c
+++ b/arch/mips/mips-boards/generic/display.c
@@ -19,9 +19,14 @@
  */
 
 #include <linux/compiler.h>
+#include <linux/timer.h>
 #include <asm/io.h>
 #include <asm/mips-boards/generic.h>
 
+extern const char display_string[];
+static unsigned int display_count;
+static unsigned int max_display_count;
+
 void mips_display_message(const char *str)
 {
 	static unsigned int __iomem *display = NULL;
@@ -37,3 +42,22 @@
 		         writel(' ', display + i);
 	}
 }
+
+static void scroll_display_message(unsigned long data);
+static DEFINE_TIMER(mips_scroll_timer, scroll_display_message, HZ, 0);
+
+static void scroll_display_message(unsigned long data)
+{
+	mips_display_message(&display_string[display_count++]);
+	if (display_count == max_display_count)
+		display_count = 0;
+
+	mod_timer(&mips_scroll_timer, jiffies + HZ);
+}
+
+void mips_scroll_message(void)
+{
+	del_timer_sync(&mips_scroll_timer);
+	max_display_count = strlen(display_string) + 1 - 8;
+	mod_timer(&mips_scroll_timer, jiffies + 1);
+}