text: /*
   * Copyright (c) 2016 Intel Corporation
   *
   * SPDX-License-Identifier: Apache-2.0
   */
  
  /**
   * @file
   * @brief Nios II C-domain interrupt management code for use with Internal
   * Interrupt Controller (IIC)
   */
  
  
  #include <kernel.h>
  #include <kernel_structs.h>
  #include <arch/cpu.h>
  #include <irq.h>
  #include <sw_isr_table.h>
  #include <ksched.h>
  #include <kswap.h>
  #include <tracing/tracing.h>
  #include <logging/log.h>
  LOG_MODULE_DECLARE(os);
  
  FUNC_NORETURN void z_irq_spurious(const void *unused)
  {
  	ARG_UNUSED(unused);
  	LOG_ERR("Spurious interrupt detected! ipending: %x",
  		z_nios2_creg_read(NIOS2_CR_IPENDING));
  	z_nios2_fatal_error(K_ERR_SPURIOUS_IRQ, NULL);
  }
  
  
  void arch_irq_enable(unsigned int irq)
  {
  	uint32_t ienable;
  	unsigned int key;
  
  	key = irq_lock();
  
  	ienable = z_nios2_creg_read(NIOS2_CR_IENABLE);
  	ienable |= BIT(irq);
  	z_nios2_creg_write(NIOS2_CR_IENABLE, ienable);
  
  	irq_unlock(key);
  };
  
  
  
  void arch_irq_disable(unsigned int irq)
  {
  	uint32_t ienable;
  	unsigned int key;
  
  	key = irq_lock();
  
  	ienable = z_nios2_creg_read(NIOS2_CR_IENABLE);
  	ienable &= ~BIT(irq);
  	z_nios2_creg_write(NIOS2_CR_IENABLE, ienable);
  
  	irq_unlock(key);
  };
  
  int arch_irq_is_enabled(unsigned int irq)
  {
  	uint32_t ienable;
  
  	ienable = z_nios2_creg_read(NIOS2_CR_IENABLE);
  	return ienable & BIT(irq);
  }
  
  /**
   * @brief Interrupt demux function
   *
   * Given a bitfield of pending interrupts, execute the appropriate handler
   *
   * @param ipending Bitfield of interrupts
   */
  void _enter_irq(uint32_t ipending)
  {
  	int index;
  
  #ifdef CONFIG_EXECUTION_BENCHMARKING
  	extern void read_timer_start_of_isr(void);
  	read_timer_start_of_isr();
  #endif
  
  	_kernel.cpus[0].nested++;
  
  #ifdef CONFIG_IRQ_OFFLOAD
  	z_irq_do_offload();
  #endif
  
  	while (ipending) {
  		struct _isr_table_entry *ite;
  
  #ifdef CONFIG_TRACING_ISR
  		sys_trace_isr_enter();
  #endif
  
  		index = find_lsb_set(ipending) - 1;
  		ipending &= ~BIT(index);
  
  		ite = &_sw_isr_table[index];
  
  #ifdef CONFIG_EXECUTION_BENCHMARKING
  		extern void read_timer_end_of_isr(void);
  		read_timer_end_of_isr();
  #endif
  		ite->isr(ite->arg);
  #ifdef CONFIG_TRACING_ISR
  		sys_trace_isr_exit();
  #endif
  	}
  
  	_kernel.cpus[0].nested--;
  #ifdef CONFIG_STACK_SENTINEL
  	z_check_stack_sentinel();
  #endif
  }
  
  #ifdef CONFIG_DYNAMIC_INTERRUPTS
  int arch_irq_connect_dynamic(unsigned int irq, unsigned int priority,
  			     void (*routine)(const void *parameter),
  			     const void *parameter, uint32_t flags)
  {
  	ARG_UNUSED(flags);
  	ARG_UNUSED(priority);
  
  	z_isr_install(irq, routine, parameter);
  	return irq;
  }
  #endif /* CONFIG_DYNAMIC_INTERRUPTS */
  