/*
 * FreeRTOS Kernel <DEVELOPMENT BRANCH>
 * Copyright (C) 2021 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
 *
 * SPDX-License-Identifier: MIT
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * https://www.FreeRTOS.org
 * https://github.com/FreeRTOS
 *
 */

/* Kernel includes. */
#include "FreeRTOS.h"

/* Machine includes */
#include <tc1782.h>
#include <machine/intrinsics.h>
#include <machine/cint.h>
/*---------------------------------------------------------------------------*/

/*
 * This reference is required by the Save/Restore Context Macros.
 */
extern volatile uint32_t *pxCurrentTCB;
/*-----------------------------------------------------------*/

/*
 * This file contains base definitions for all of the possible traps in the system.
 * It is suggested to provide implementations for all of the traps but for
 * the time being they simply trigger a DEBUG instruction so that it is easy
 * to see what caused a particular trap.
 *
 * Trap Class 6, the SYSCALL, is used exclusively by the operating system.
 */

/* The Trap Classes. */
#define portMMU_TRAP                                        0
#define portIPT_TRAP                                        1
#define portIE_TRAP                                         2
#define portCM_TRAP                                         3
#define portSBP_TRAP                                        4
#define portASSERT_TRAP                                     5
#define portNMI_TRAP                                        7

/* MMU Trap Identifications. */
#define portTIN_MMU_VIRTUAL_ADDRESS_FILL                    0
#define portTIN_MMU_VIRTUAL_ADDRESS_PROTECTION              1

/* Internal Protection Trap Identifications. */
#define portTIN_IPT_PRIVILIGED_INSTRUCTION                  1
#define portTIN_IPT_MEMORY_PROTECTION_READ                  2
#define portTIN_IPT_MEMORY_PROTECTION_WRITE                 3
#define portTIN_IPT_MEMORY_PROTECTION_EXECUTION             4
#define portTIN_IPT_MEMORY_PROTECTION_PERIPHERAL_ACCESS     5
#define portTIN_IPT_MEMORY_PROTECTION_NULL_ADDRESS          6
#define portTIN_IPT_MEMORY_PROTECTION_GLOBAL_REGISTER_WRITE_PROTECTION  7

/* Instruction Error Trap Identifications. */
#define portTIN_IE_ILLEGAL_OPCODE                           1
#define portTIN_IE_UNIMPLEMENTED_OPCODE                     2
#define portTIN_IE_INVALID_OPERAND                          3
#define portTIN_IE_DATA_ADDRESS_ALIGNMENT                   4
#define portTIN_IE_INVALID_LOCAL_MEMORY_ADDRESS             5

/* Context Management Trap Identifications. */
#define portTIN_CM_FREE_CONTEXT_LIST_DEPLETION              1
#define portTIN_CM_CALL_DEPTH_OVERFLOW                      2
#define portTIN_CM_CALL_DEPTH_UNDEFLOW                      3
#define portTIN_CM_FREE_CONTEXT_LIST_UNDERFLOW              4
#define portTIN_CM_CALL_STACK_UNDERFLOW                     5
#define portTIN_CM_CONTEXT_TYPE                             6
#define portTIN_CM_NESTING_ERROR                            7

/* System Bus and Peripherals Trap Identifications. */
#define portTIN_SBP_PROGRAM_FETCH_SYNCHRONOUS_ERROR         1
#define portTIN_SBP_DATA_ACCESS_SYNCHRONOUS_ERROR           2
#define portTIN_SBP_DATA_ACCESS_ASYNCHRONOUS_ERROR          3
#define portTIN_SBP_COPROCESSOR_TRAP_ASYNCHRONOUS_ERROR     4
#define portTIN_SBP_PROGRAM_MEMORY_INTEGRITY_ERROR          5
#define portTIN_SBP_DATA_MEMORY_INTEGRITY_ERROR             6

/* Assertion Trap Identifications. */
#define portTIN_ASSERT_ARITHMETIC_OVERFLOW                  1
#define portTIN_ASSERT_STICKY_ARITHMETIC_OVERFLOW           2

/* Non-maskable Interrupt Trap Identifications. */
#define portTIN_NMI_NON_MASKABLE_INTERRUPT                  0
/*---------------------------------------------------------------------------*/

void vMMUTrap( int iTrapIdentification ) __attribute__( ( longcall, weak ) );
void vInternalProtectionTrap( int iTrapIdentification ) __attribute__( ( longcall, weak ) );
void vInstructionErrorTrap( int iTrapIdentification ) __attribute__( ( longcall, weak ) );
void vContextManagementTrap( int iTrapIdentification ) __attribute__( ( longcall, weak ) );
void vSystemBusAndPeripheralsTrap( int iTrapIdentification ) __attribute__( ( longcall, weak ) );
void vAssertionTrap( int iTrapIdentification ) __attribute__( ( longcall, weak ) );
void vNonMaskableInterruptTrap( int iTrapIdentification ) __attribute__( ( longcall, weak ) );
/*---------------------------------------------------------------------------*/

void vTrapInstallHandlers( void )
{
    if( 0 == _install_trap_handler ( portMMU_TRAP, vMMUTrap ) )
    {
        _debug();
    }

    if( 0 == _install_trap_handler ( portIPT_TRAP, vInternalProtectionTrap ) )
    {
        _debug();
    }

    if( 0 == _install_trap_handler ( portIE_TRAP, vInstructionErrorTrap ) )
    {
        _debug();
    }

    if( 0 == _install_trap_handler ( portCM_TRAP, vContextManagementTrap ) )
    {
        _debug();
    }

    if( 0 == _install_trap_handler ( portSBP_TRAP, vSystemBusAndPeripheralsTrap ) )
    {
        _debug();
    }

    if( 0 == _install_trap_handler ( portASSERT_TRAP, vAssertionTrap ) )
    {
        _debug();
    }

    if( 0 == _install_trap_handler ( portNMI_TRAP, vNonMaskableInterruptTrap ) )
    {
        _debug();
    }
}
/*-----------------------------------------------------------*/

void vMMUTrap( int iTrapIdentification )
{
    switch( iTrapIdentification )
    {
    case portTIN_MMU_VIRTUAL_ADDRESS_FILL:
    case portTIN_MMU_VIRTUAL_ADDRESS_PROTECTION:
    default:
        _debug();
        break;
    }
}
/*---------------------------------------------------------------------------*/

void vInternalProtectionTrap( int iTrapIdentification )
{
    /* Deliberate fall through to default. */
    switch( iTrapIdentification )
    {
        case portTIN_IPT_PRIVILIGED_INSTRUCTION:
            /* Instruction is not allowed at current execution level, eg DISABLE at User-0. */

        case portTIN_IPT_MEMORY_PROTECTION_READ:
            /* Load word using invalid address. */

        case portTIN_IPT_MEMORY_PROTECTION_WRITE:
            /* Store Word using invalid address. */

        case portTIN_IPT_MEMORY_PROTECTION_EXECUTION:
            /* PC jumped to an address outside of the valid range. */

        case portTIN_IPT_MEMORY_PROTECTION_PERIPHERAL_ACCESS:
            /* Access to a peripheral denied at current execution level. */

        case portTIN_IPT_MEMORY_PROTECTION_NULL_ADDRESS:
            /* NULL Pointer. */

        case portTIN_IPT_MEMORY_PROTECTION_GLOBAL_REGISTER_WRITE_PROTECTION:
            /* Tried to modify a global address pointer register. */

        default:

            pxCurrentTCB[ 0 ] = __MFCR( $PCXI );
            _debug();
            break;
    }
}
/*---------------------------------------------------------------------------*/

void vInstructionErrorTrap( int iTrapIdentification )
{
    /* Deliberate fall through to default. */
    switch( iTrapIdentification )
    {
        case portTIN_IE_ILLEGAL_OPCODE:
        case portTIN_IE_UNIMPLEMENTED_OPCODE:
        case portTIN_IE_INVALID_OPERAND:
        case portTIN_IE_DATA_ADDRESS_ALIGNMENT:
        case portTIN_IE_INVALID_LOCAL_MEMORY_ADDRESS:
        default:
            _debug();
            break;
    }
}
/*---------------------------------------------------------------------------*/

void vContextManagementTrap( int iTrapIdentification )
{
    /* Deliberate fall through to default. */
    switch( iTrapIdentification )
    {
        case portTIN_CM_FREE_CONTEXT_LIST_DEPLETION:
        case portTIN_CM_CALL_DEPTH_OVERFLOW:
        case portTIN_CM_CALL_DEPTH_UNDEFLOW:
        case portTIN_CM_FREE_CONTEXT_LIST_UNDERFLOW:
        case portTIN_CM_CALL_STACK_UNDERFLOW:
        case portTIN_CM_CONTEXT_TYPE:
        case portTIN_CM_NESTING_ERROR:
        default:
            _debug();
            break;
    }
}
/*---------------------------------------------------------------------------*/

void vSystemBusAndPeripheralsTrap( int iTrapIdentification )
{
    /* Deliberate fall through to default. */
    switch( iTrapIdentification )
    {
        case portTIN_SBP_PROGRAM_FETCH_SYNCHRONOUS_ERROR:
        case portTIN_SBP_DATA_ACCESS_SYNCHRONOUS_ERROR:
        case portTIN_SBP_DATA_ACCESS_ASYNCHRONOUS_ERROR:
        case portTIN_SBP_COPROCESSOR_TRAP_ASYNCHRONOUS_ERROR:
        case portTIN_SBP_PROGRAM_MEMORY_INTEGRITY_ERROR:
        case portTIN_SBP_DATA_MEMORY_INTEGRITY_ERROR:
        default:
            _debug();
            break;
    }
}
/*---------------------------------------------------------------------------*/

void vAssertionTrap( int iTrapIdentification )
{
    /* Deliberate fall through to default. */
    switch( iTrapIdentification )
    {
        case portTIN_ASSERT_ARITHMETIC_OVERFLOW:
        case portTIN_ASSERT_STICKY_ARITHMETIC_OVERFLOW:
        default:
            _debug();
            break;
    }
}
/*---------------------------------------------------------------------------*/

void vNonMaskableInterruptTrap( int iTrapIdentification )
{
    /* Deliberate fall through to default. */
    switch( iTrapIdentification )
    {
        case portTIN_NMI_NON_MASKABLE_INTERRUPT:
        default:
            _debug();
            break;
    }
}
/*---------------------------------------------------------------------------*/