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/****************************************************************************
* arch/z80/src/z8/z8_irq.c
*
* Copyright (C) 2008 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <nuttx/arch.h>
#include <nuttx/irq.h>
#include <ez8.h>
#include "chip/switch.h"
#include "up_internal.h"
/****************************************************************************
* Private Definitions
****************************************************************************/
/****************************************************************************
* Public Data
****************************************************************************/
/* This structure holds information about the current interrupt processing state */
struct z8_irqstate_s g_z8irqstate;
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: irqsave
*
* Description:
* Disable all interrupts; return previous interrupt state
*
****************************************************************************/
irqstate_t irqsave(void)
{
/* Bit 7 (IRQE) of the IRQCTL register determines if interrupts were
* enabled when this function was called.
*/
register irqstate_t retval = getreg8(IRQCTL);
/* Disable interrupts */
DI();
/* Return the previous interrupt state */
return retval;
}
/****************************************************************************
* Name: irqrestore
*
* Description:
* Restore previous interrupt state
*
****************************************************************************/
void irqrestore(irqstate_t flags)
{
/* Bit 7 (IRQE) of the IRQCTL register determines if interrupts were
* enabled when irqsave() was called.
*/
if ((flags & 0x80) != 0)
{
/* The IRQE bit was set, re-enable interrupts */
EI();
}
}
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