arch/arc/plat-arcfpga/irq.c

   1 /*
   2  * ARC FPGA Platform IRQ hookups
   3  *
   4  * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/interrupt.h>
  12 #include <plat/irq.h>
  13
  14 void __init plat_fpga_init_IRQ(void)
  15 {
  16         /*
  17          * SMP Hack because UART IRQ hardwired to cpu0 (boot-cpu) but if the
  18          * request_irq() comes from any other CPU, the low level IRQ unamsking
  19          * essential for getting Interrupts won't be enabled on cpu0, locking
  20          * up the UART state machine.
  21          */
  22 #ifdef CONFIG_SMP
  23         arch_unmask_irq(UART0_IRQ);
  24 #endif
  25 }