nuttx/arch/ceva/src/common/ceva_doirq.c
2022-11-22 16:27:56 +08:00

107 lines
3.6 KiB
C

/****************************************************************************
* arch/ceva/src/common/ceva_doirq.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/arch.h>
#include "sched/sched.h"
#include "ceva_internal.h"
/****************************************************************************
* Public Data
****************************************************************************/
/* g_current_regs[] holds a references to the current interrupt level
* register storage structure. If is non-NULL only during interrupt
* processing. Access to g_current_regs[] must be through the macro
* CURRENT_REGS for portability.
*/
uint32_t *volatile g_current_regs[CONFIG_SMP_NCPUS];
/****************************************************************************
* Public Functions
****************************************************************************/
uint32_t *ceva_doirq(int irq, uint32_t *regs)
{
/* Is it the outermost interrupt? */
if (CURRENT_REGS != NULL)
{
/* No, simply deliver the IRQ because only the outermost nested
* interrupt can result in a context switch.
*/
irq_dispatch(irq, regs);
}
else
{
/* Current regs non-zero indicates that we are processing an interrupt;
* CURRENT_REGS is also used to manage interrupt level context
* switches.
*/
CURRENT_REGS = regs;
/* Deliver the IRQ */
irq_dispatch(irq, regs);
/* If a context switch occurred while processing the interrupt then
* CURRENT_REGS may have change value. If we return any value
* different from the input regs, then the lower level will know that
* a context switch occurred during interrupt processing.
*/
if (regs != CURRENT_REGS)
{
restore_critical_section();
regs = CURRENT_REGS;
}
/* Restore the previous value of CURRENT_REGS. NULL would indicate
* that we are no longer in an interrupt handler.
* It will be non-NULL if we are returning from a nested interrupt.
*/
CURRENT_REGS = NULL;
if (regs != (uint32_t *)regs[REG_SP])
{
/* We are returning with a pending context switch. This case is
* different because in this case, the register save structure
* does not lie on the stack but, rather within other storage.
* We'll have to copy some values to the stack.
*/
memcpy((uint32_t *)regs[REG_SP], regs, XCPTCONTEXT_SIZE);
regs = (uint32_t *)regs[REG_SP];
}
}
return regs;
}