nuttx/arch/ceva/src/common/ceva_switchcontext.c
Alin Jerpelea 6e268f3c45 arch/ceva: migrate to SPDX identifier
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.

Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
2024-12-02 22:43:23 +08:00

105 lines
3.5 KiB
C

/****************************************************************************
* arch/ceva/src/common/ceva_switchcontext.c
*
* SPDX-License-Identifier: Apache-2.0
*
* 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/arch.h>
#include <arch/syscall.h>
#include "sched/sched.h"
#include "ceva_internal.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: ceva_switchcontext
*
* Description:
* Save the current thread context and restore the specified context.
* Full prototype is:
*
* void ceva_switchcontext(uint32_t **saveregs, uint32_t *restoreregs);
*
* Return:
* None
*
****************************************************************************/
void ceva_switchcontext(uint32_t **saveregs, uint32_t *restoreregs)
{
/* Let sys_call2() do all of the work */
sys_call2(SYS_switch_context, (uintptr_t)saveregs, (uintptr_t)restoreregs);
}
/****************************************************************************
* Name: up_switch_context
*
* Description:
* A task is currently in the ready-to-run list but has been prepped
* to execute. Restore its context, and start execution.
*
* Input Parameters:
* tcb: Refers to the head task of the ready-to-run list
* which will be executed.
* rtcb: Refers to the running task which will be blocked.
*
****************************************************************************/
void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
{
/* Are we in an interrupt handler? */
if (up_current_regs())
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
rtcb->xcp.regs = up_current_regs();
/* Then switch contexts */
up_set_current_regs(tcb->xcp.regs);
}
/* No, then we will need to perform the user context switch */
else
{
/* Switch context to the context of the task at the head of the
* ready to run list.
*/
ceva_switchcontext(&rtcb->xcp.regs, tcb->xcp.regs);
/* ceva_switchcontext forces a context switch to the task at the
* head of the ready-to-run list. It does not 'return' in the
* normal sense. When it does return, it is because the blocked
* task is again ready to run and has execution priority.
*/
}
}