177 lines
6.5 KiB
C
177 lines
6.5 KiB
C
/****************************************************************************
|
|
* arch/misoc/src/minerva/minerva_schedulesigaction.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 <stdint.h>
|
|
#include <sched.h>
|
|
#include <debug.h>
|
|
|
|
#include <nuttx/irq.h>
|
|
#include <nuttx/arch.h>
|
|
#include <arch/minerva/irq.h>
|
|
#include <arch/minerva/csrdefs.h>
|
|
|
|
#include "sched/sched.h"
|
|
#include "minerva.h"
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: up_schedule_sigaction
|
|
*
|
|
* Description:
|
|
* This function is called by the OS when one or more
|
|
* signal handling actions have been queued for execution.
|
|
* The architecture specific code must configure things so
|
|
* that the 'sigdeliver' callback is executed on the thread
|
|
* specified by 'tcb' as soon as possible.
|
|
*
|
|
* This function may be called from interrupt handling logic.
|
|
*
|
|
* This operation should not cause the task to be unblocked
|
|
* nor should it cause any immediate execution of sigdeliver.
|
|
* Typically, a few cases need to be considered:
|
|
*
|
|
* (1) This function may be called from an interrupt handler
|
|
* During interrupt processing, all xcptcontext structures
|
|
* should be valid for all tasks. That structure should
|
|
* be modified to invoke sigdeliver() either on return
|
|
* from (this) interrupt or on some subsequent context
|
|
* switch to the recipient task.
|
|
* (2) If not in an interrupt handler and the tcb is NOT
|
|
* the currently executing task, then again just modify
|
|
* the saved xcptcontext structure for the recipient
|
|
* task so it will invoke sigdeliver when that task is
|
|
* later resumed.
|
|
* (3) If not in an interrupt handler and the tcb IS the
|
|
* currently executing task -- just call the signal
|
|
* handler now.
|
|
*
|
|
* Assumptions:
|
|
* Called from critical section
|
|
*
|
|
****************************************************************************/
|
|
|
|
void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
|
|
{
|
|
sinfo("tcb=%p sigdeliver=%p\n", tcb, sigdeliver);
|
|
|
|
/* Refuse to handle nested signal actions */
|
|
|
|
if (!tcb->xcp.sigdeliver)
|
|
{
|
|
/* First, handle some special cases when the signal is being delivered
|
|
* to the currently executing task.
|
|
*/
|
|
|
|
sinfo("rtcb=%p g_current_regs=%p\n", this_task(), g_current_regs);
|
|
|
|
if (tcb == this_task())
|
|
{
|
|
/* CASE 1: We are not in an interrupt handler and a task is
|
|
* signalling itself for some reason.
|
|
*/
|
|
|
|
if (!g_current_regs)
|
|
{
|
|
/* In this case just deliver the signal now. */
|
|
|
|
sigdeliver(tcb);
|
|
}
|
|
|
|
/* CASE 2: We are in an interrupt handler AND the interrupted task
|
|
* is the same as the one that must receive the signal, then we
|
|
* will have to modify the return state as well as the state in
|
|
* the TCB.
|
|
*
|
|
* Hmmm... there looks like a latent bug here: The following logic
|
|
* would fail in the strange case where we are in an interrupt
|
|
* handler, the thread is signalling itself, but a context switch
|
|
* to another task has occurred so that g_current_regs does not
|
|
* refer to the thread of this_task()!
|
|
*/
|
|
|
|
else
|
|
{
|
|
/* Save the return EPC and STATUS registers. These will be
|
|
* restored by the signal trampoline after the signals have
|
|
* been delivered.
|
|
*/
|
|
|
|
tcb->xcp.sigdeliver = sigdeliver;
|
|
tcb->xcp.saved_epc = g_current_regs[REG_CSR_MEPC];
|
|
|
|
/* Then set up to vector to the trampoline with interrupts
|
|
* disabled
|
|
*/
|
|
|
|
g_current_regs[REG_CSR_MEPC] = (uint32_t) minerva_sigdeliver;
|
|
g_current_regs[REG_CSR_MSTATUS] &= ~CSR_MSTATUS_MIE;
|
|
|
|
/* And make sure that the saved context in the TCB is the same
|
|
* as the interrupt return context.
|
|
*/
|
|
|
|
misoc_savestate(tcb->xcp.regs);
|
|
|
|
sinfo("PC/STATUS Saved: %08x/%08x New: %08x/%08x\n",
|
|
tcb->xcp.saved_epc, tcb->xcp.saved_status,
|
|
g_current_regs[REG_CSR_MEPC],
|
|
g_current_regs[REG_CSR_MSTATUS]);
|
|
}
|
|
}
|
|
|
|
/* Otherwise, we are (1) signaling a task is not running from an
|
|
* interrupt handler or (2) we are not in an interrupt handler and the
|
|
* running task is signalling some non-running task.
|
|
*/
|
|
|
|
else
|
|
{
|
|
/* Save the return EPC and STATUS registers. These will be
|
|
* restored by the signal trampoline after the signals have been
|
|
* delivered.
|
|
*/
|
|
|
|
tcb->xcp.sigdeliver = sigdeliver;
|
|
tcb->xcp.saved_epc = tcb->xcp.regs[REG_CSR_MEPC];
|
|
tcb->xcp.saved_int_ctx = tcb->xcp.regs[REG_CSR_MSTATUS];
|
|
|
|
/* Then set up to vector to the trampoline with interrupts
|
|
* disabled
|
|
*/
|
|
|
|
tcb->xcp.regs[REG_CSR_MEPC] = (uint32_t) minerva_sigdeliver;
|
|
g_current_regs[REG_CSR_MSTATUS] &= ~CSR_MSTATUS_MIE;
|
|
|
|
sinfo("PC/STATUS Saved: %08x/%08x New: %08x/%08x\n",
|
|
tcb->xcp.saved_epc, tcb->xcp.saved_status,
|
|
tcb->xcp.regs[REG_CSR_MEPC], tcb->xcp.regs[REG_CSR_MSTATUS]);
|
|
}
|
|
}
|
|
}
|