/*
   * H8/300H interrupt controller driver
   *
   * Copyright 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
   */
  
  #include <linux/init.h>
  #include <linux/irq.h>
  #include <linux/irqchip.h>
  #include <linux/of_address.h>
  #include <linux/of_irq.h>
  #include <asm/io.h>

  static const char ipr_bit[] = {
  	 7,  6,  5,  5,
  	 4,  4,  4,  4,  3,  3,  3,  3,
  	 2,  2,  2,  2,  1,  1,  1,  1,
  	 0,  0,  0,  0, 15, 15, 15, 15,
  	14, 14, 14, 14, 13, 13, 13, 13,
  	-1, -1, -1, -1, 11, 11, 11, 11,
  	10, 10, 10, 10,  9,  9,  9,  9,
  };

  static void __iomem *intc_baseaddr;

  #define IPR (intc_baseaddr + 6)

  
  static void h8300h_disable_irq(struct irq_data *data)
  {
  	int bit;
  	int irq = data->irq - 12;
  
  	bit = ipr_bit[irq];
  	if (bit >= 0) {
  		if (bit < 8)
  			ctrl_bclr(bit & 7, IPR);
  		else
  			ctrl_bclr(bit & 7, (IPR+1));
  	}
  }
  
  static void h8300h_enable_irq(struct irq_data *data)
  {
  	int bit;
  	int irq = data->irq - 12;
  
  	bit = ipr_bit[irq];
  	if (bit >= 0) {
  		if (bit < 8)
  			ctrl_bset(bit & 7, IPR);
  		else
  			ctrl_bset(bit & 7, (IPR+1));
  	}
  }
  
  struct irq_chip h8300h_irq_chip = {
  	.name		= "H8/300H-INTC",
  	.irq_enable	= h8300h_enable_irq,
  	.irq_disable	= h8300h_disable_irq,
  };
  
  static int irq_map(struct irq_domain *h, unsigned int virq,
  		   irq_hw_number_t hw_irq_num)
  {
         irq_set_chip_and_handler(virq, &h8300h_irq_chip, handle_simple_irq);
  
         return 0;
  }
  
  static struct irq_domain_ops irq_ops = {
         .map    = irq_map,
         .xlate  = irq_domain_xlate_onecell,
  };
  
  static int __init h8300h_intc_of_init(struct device_node *intc,
  				      struct device_node *parent)
  {
  	struct irq_domain *domain;
  
  	intc_baseaddr = of_iomap(intc, 0);
  	BUG_ON(!intc_baseaddr);
  
  	/* All interrupt priority low */

  	writeb(0x00, IPR + 0);
  	writeb(0x00, IPR + 1);

  
  	domain = irq_domain_add_linear(intc, NR_IRQS, &irq_ops, NULL);
  	BUG_ON(!domain);
  	irq_set_default_host(domain);
  	return 0;
  }
  
  IRQCHIP_DECLARE(h8300h_intc, "renesas,h8300h-intc", h8300h_intc_of_init);