arch/arc/kernel/irq.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2011-12 Synopsys, Inc. (www.synopsys.com)
   4  */
   5
   6 #include <linux/interrupt.h>
   7 #include <linux/irqchip.h>
   8 #include <asm/mach_desc.h>
   9
  10 #include <asm/irq_regs.h>
  11 #include <asm/smp.h>
  12
  13 /*
  14  * Late Interrupt system init called from start_kernel for Boot CPU only
  15  *
  16  * Since slab must already be initialized, platforms can start doing any
  17  * needed request_irq( )s
  18  */
  19 void __init init_IRQ(void)
  20 {
  21         /*
  22          * process the entire interrupt tree in one go
  23          * Any external intc will be setup provided DT chains them
  24          * properly
  25          */
  26         irqchip_init();
  27
  28 #ifdef CONFIG_SMP
  29         /* a SMP H/w block could do IPI IRQ request here */
  30         if (plat_smp_ops.init_per_cpu)
  31                 plat_smp_ops.init_per_cpu(smp_processor_id());
  32 #endif
  33
  34         if (machine_desc->init_per_cpu)
  35                 machine_desc->init_per_cpu(smp_processor_id());
  36 }
  37
  38 /*
  39  * "C" Entry point for any ARC ISR, called from low level vector handler
  40  * @irq is the vector number read from ICAUSE reg of on-chip intc
  41  */
  42 void arch_do_IRQ(unsigned int hwirq, struct pt_regs *regs)
  43 {
  44         struct pt_regs *old_regs;
  45
  46         irq_enter();
  47         old_regs = set_irq_regs(regs);
  48         generic_handle_domain_irq(NULL, hwirq);
  49         set_irq_regs(old_regs);
  50         irq_exit();
  51 }