/****************************************************************************
 * arch/z80/include/z80/irq.h
 * arch/chip/irq.h
 *
 *   Copyright (C) 2007-2009, 2015 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/* This file should never be included directed but, rather,
 * only indirectly through nuttx/irq.h (via arch/irq.h)
 */

#ifndef __ARCH_Z80_INCLUDE_Z80_IRQ_H
#define __ARCH_Z80_INCLUDE_Z80_IRQ_H

/****************************************************************************
 * Included Files
 ****************************************************************************/

#ifndef __ASSEMBLY__
#  include <stdint.h>
#endif

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/* Z80 Interrupts */

#define Z80_RST0         (0)
#define Z80_RST1         (1)
#define Z80_RST2         (2)
#define Z80_RST3         (3)
#define Z80_RST4         (4)
#define Z80_RST5         (5)
#define Z80_RST6         (6)
#define Z80_RST7         (7)

#define Z80_IRQ_SYSTIMER Z80_RST7
#define NR_IRQS          (8)

/* IRQ Stack Frame Format
 *
 * This stack frame is created on each interrupt.  These registers are stored
 * in the TCB to many context switches.
 */

#define XCPT_I               (0) /* Offset 0: Saved I w/interrupt state in carry */
#define XCPT_BC              (1) /* Offset 1: Saved BC register */
#define XCPT_DE              (2) /* Offset 2: Saved DE register */
#define XCPT_IX              (3) /* Offset 3: Saved IX register */
#define XCPT_IY              (4) /* Offset 4: Saved IY register */
#define XCPT_SP              (5) /* Offset 5: Offset to SP at time of interrupt */
#define XCPT_HL              (6) /* Offset 6: Saved HL register */
#define XCPT_AF              (7) /* Offset 7: Saved AF register */
#define XCPT_PC              (8) /* Offset 8: Offset to PC at time of interrupt */

#define XCPTCONTEXT_REGS     (9)
#define XCPTCONTEXT_SIZE     (2 * XCPTCONTEXT_REGS)

/****************************************************************************
 * Public Types
 ****************************************************************************/

#ifndef __ASSEMBLY__

/* This is the type of the register save array */

typedef uint16_t chipreg_t;

/* This struct defines the way the registers are stored. */

struct xcptcontext
{
  /* Register save area */

  chipreg_t regs[XCPTCONTEXT_REGS];

  /* The following function pointer is non-zero if there
   * are pending signals to be processed.
   */

#ifndef CONFIG_DISABLE_SIGNALS
  CODE void *sigdeliver; /* Actual type is sig_deliver_t */

  /* The following retains that state during signal execution */

  uint16_t saved_pc;	/* Saved return address */
  uint16_t saved_i;		/* Saved interrupt state */
#endif
};
#endif

/****************************************************************************
 * Inline functions
 ****************************************************************************/

/****************************************************************************
 * Public Data
 ****************************************************************************/

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/

#ifndef __ASSEMBLY__
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif

irqstate_t irqsave(void) __naked;
void       irqrestore(irqstate_t flags) __naked;

#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif

#endif /* __ARCH_Z80_INCLUDE_Z80_IRQ_H */

