text: /* $Id: irq.c,v 1.1.2.4 2002/11/04 20:33:56 lethal Exp $
   *
   * arch/sh/boards/cqreek/irq.c
   *
   * Copyright (C) 2000  Niibe Yutaka
   *
   * CqREEK IDE/ISA Bridge Support.
   *
   */
  
  #include <linux/irq.h>
  #include <linux/init.h>
  
  #include <asm/cqreek/cqreek.h>
  #include <asm/io.h>
  #include <asm/io_generic.h>
  #include <asm/irq.h>
  #include <asm/machvec.h>
  #include <asm/machvec_init.h>
  #include <asm/rtc.h>
  
  struct cqreek_irq_data {
  	unsigned short mask_port;	/* Port of Interrupt Mask Register */
  	unsigned short stat_port;	/* Port of Interrupt Status Register */
  	unsigned short bit;		/* Value of the bit */
  };
  static struct cqreek_irq_data cqreek_irq_data[NR_IRQS];
  
  static void disable_cqreek_irq(unsigned int irq)
  {
  	unsigned long flags;
  	unsigned short mask;
  	unsigned short mask_port = cqreek_irq_data[irq].mask_port;
  	unsigned short bit = cqreek_irq_data[irq].bit;
  
  	local_irq_save(flags);
  	/* Disable IRQ */
  	mask = inw(mask_port) & ~bit;
  	outw_p(mask, mask_port);
  	local_irq_restore(flags);
  }
  
  static void enable_cqreek_irq(unsigned int irq)
  {
  	unsigned long flags;
  	unsigned short mask;
  	unsigned short mask_port = cqreek_irq_data[irq].mask_port;
  	unsigned short bit = cqreek_irq_data[irq].bit;
  
  	local_irq_save(flags);
  	/* Enable IRQ */
  	mask = inw(mask_port) | bit;
  	outw_p(mask, mask_port);
  	local_irq_restore(flags);
  }
  
  static void mask_and_ack_cqreek(unsigned int irq)
  {
  	unsigned short stat_port = cqreek_irq_data[irq].stat_port;
  	unsigned short bit = cqreek_irq_data[irq].bit;
  
  	disable_cqreek_irq(irq);
  	/* Clear IRQ (it might be edge IRQ) */
  	inw(stat_port);
  	outw_p(bit, stat_port);
  }
  
  static void end_cqreek_irq(unsigned int irq)
  {
  	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
  		enable_cqreek_irq(irq);
  }
  
  static unsigned int startup_cqreek_irq(unsigned int irq)
  { 
  	enable_cqreek_irq(irq);
  	return 0;
  }
  
  static void shutdown_cqreek_irq(unsigned int irq)
  {
  	disable_cqreek_irq(irq);
  }
  
  static struct hw_interrupt_type cqreek_irq_type = {
  	.typename = "CqREEK-IRQ",
  	.startup = startup_cqreek_irq,
  	.shutdown = shutdown_cqreek_irq,
  	.enable = enable_cqreek_irq,
  	.disable = disable_cqreek_irq,
  	.ack = mask_and_ack_cqreek,
  	.end = end_cqreek_irq
  };
  
  int cqreek_has_ide, cqreek_has_isa;
  
  /* XXX: This is just for test for my NE2000 ISA board
     What we really need is virtualized IRQ and demultiplexer like HP600 port */
  void __init init_cqreek_IRQ(void)
  {
  	if (cqreek_has_ide) {
  		cqreek_irq_data[14].mask_port = BRIDGE_IDE_INTR_MASK;
  		cqreek_irq_data[14].stat_port = BRIDGE_IDE_INTR_STAT;
  		cqreek_irq_data[14].bit = 1;
  
  		irq_desc[14].handler = &cqreek_irq_type;
  		irq_desc[14].status = IRQ_DISABLED;
  		irq_desc[14].action = 0;
  		irq_desc[14].depth = 1;
  
  		disable_cqreek_irq(14);
  	}
  
  	if (cqreek_has_isa) {
  		cqreek_irq_data[10].mask_port = BRIDGE_ISA_INTR_MASK;
  		cqreek_irq_data[10].stat_port = BRIDGE_ISA_INTR_STAT;
  		cqreek_irq_data[10].bit = (1 << 10);
  
  		/* XXX: Err... we may need demultiplexer for ISA irq... */
  		irq_desc[10].handler = &cqreek_irq_type;
  		irq_desc[10].status = IRQ_DISABLED;
  		irq_desc[10].action = 0;
  		irq_desc[10].depth = 1;
  
  		disable_cqreek_irq(10);
  	}
  }
  
  