/****************************************************************************
* arch/z80/src/z8/z8_irq.c
*
* Copyright (C) 2008-2009 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <ez8.h>
#include <nuttx/arch.h>
#include <nuttx/irq.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: up_irqinitialize
****************************************************************************/
void up_irqinitialize(void)
{
/* Clear and disable all interrupts. Set all to priority 0. */
putreg8(0xff, IRQ0);
putreg8(0xff, IRQ1);
putreg8(0xff, IRQ2);
putreg16(0x0000, IRQ0EN);
putreg16(0x0000, IRQ1EN);
putreg16(0x0000, IRQ2EN);
/* And finally, enable interrupts */
#ifndef CONFIG_SUPPRESS_INTERRUPTS
EI();
#endif
}
/****************************************************************************
* 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();
}
}
/****************************************************************************
* Name: up_disable_irq
*
* Description:
* Disable the IRQ specified by 'irq'
*
****************************************************************************/
void up_disable_irq(int irq)
{
/* System exceptions cannot be disabled */
if (irq >= Z8_IRQ0_MIN)
{
/* Disable the interrupt by clearing the corresponding bit in the
* appropriate IRQ enable high register. The enable low
* register is assumed to be zero, resulting interrupt disabled.
*/
if (irq <= Z8_IRQ0_MAX)
{
putreg8((getreg8(IRQ0ENH) & ~Z8_IRQ0_BIT(irq)), IRQ0ENH);
}
else if (irq <= Z8_IRQ1_MAX)
{
putreg8((getreg8(IRQ1ENH) & ~Z8_IRQ1_BIT(irq)), IRQ1ENH);
}
else if (irq < NR_IRQS)
{
putreg8((getreg8(IRQ2ENH) & ~Z8_IRQ2_BIT(irq)), IRQ2ENH);
}
}
}
/****************************************************************************
* Name: up_enable_irq
*
* Description:
* Enable the IRQ specified by 'irq'
*
****************************************************************************/
void up_enable_irq(int irq)
{
/* System exceptions cannot be disabled */
if (irq >= Z8_IRQ0_MIN)
{
/* Enable the interrupt by setting the corresponding bit in the
* appropriate IRQ enable high register. The enable low
* register is assumed to be zero, resulting in "nomimal" interrupt
* priority.
*/
if (irq <= Z8_IRQ0_MAX)
{
putreg8((getreg8(IRQ0ENH) | Z8_IRQ0_BIT(irq)), IRQ0ENH);
}
else if (irq <= Z8_IRQ1_MAX)
{
putreg8((getreg8(IRQ1ENH) | Z8_IRQ1_BIT(irq)), IRQ1ENH);
}
else if (irq < NR_IRQS)
{
putreg8((getreg8(IRQ2ENH) | Z8_IRQ2_BIT(irq)), IRQ2ENH);
}
}
}
/****************************************************************************
* Name: up_ack_irq
*
* Description:
* Acknowledge the interrupt
*
****************************************************************************/
void up_ack_irq(int irq)
{
/* System exceptions cannot be disabled or acknowledged */
if (irq >= Z8_IRQ0_MIN)
{
/* Acknowledge the interrupt by setting the* corresponding bit in the
* IRQ status register.
*/
if (irq <= Z8_IRQ0_MAX)
{
putreg8(Z8_IRQ0_BIT(irq), IRQ0);
}
else if (irq <= Z8_IRQ1_MAX)
{
putreg8(Z8_IRQ1_BIT(irq), IRQ2);
}
else if (irq < NR_IRQS)
{
putreg8(Z8_IRQ2_BIT(irq), IRQ2);
}
}
}
