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//*****************************************************************************
//
// aes256.c - Driver for the aes256 Module.
//
//*****************************************************************************

//*****************************************************************************
//
//! \addtogroup aes256_api aes256
//! @{
//
//*****************************************************************************

#include "inc/hw_regaccess.h"
#include "inc/hw_memmap.h"

#ifdef __MSP430_HAS_AES256__
#include "aes256.h"

#include <assert.h>

uint8_t AES256_setCipherKey(uint16_t baseAddress,
                            const uint8_t * cipherKey,
                            uint16_t keyLength)
{
    uint8_t i;
    uint16_t sCipherKey;

    HWREG16(baseAddress + OFS_AESACTL0) &= (~(AESKL_1 + AESKL_2));

    switch(keyLength)
    {
    case AES256_KEYLENGTH_128BIT:
        HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__128;
        break;

    case AES256_KEYLENGTH_192BIT:
        HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__192;
        break;

    case AES256_KEYLENGTH_256BIT:
        HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__256;
        break;

    default:
        return(STATUS_FAIL);
    }

    keyLength = keyLength / 8;

    for(i = 0; i < keyLength; i = i + 2)
    {
        sCipherKey = (uint16_t)(cipherKey[i]);
        sCipherKey = sCipherKey | ((uint16_t)(cipherKey[i + 1]) << 8);
        HWREG16(baseAddress + OFS_AESAKEY) = sCipherKey;
    }

    // Wait until key is written
    while(0x00 == (HWREG16(baseAddress + OFS_AESASTAT) & AESKEYWR))
    {
        ;
    }
    return(STATUS_SUCCESS);
}

void AES256_encryptData(uint16_t baseAddress,
                        const uint8_t * data,
                        uint8_t * encryptedData)
{
    uint8_t i;
    uint16_t tempData = 0;
    uint16_t tempVariable = 0;

    // Set module to encrypt mode
    HWREG16(baseAddress + OFS_AESACTL0) &= ~AESOP_3;

    // Write data to encrypt to module
    for(i = 0; i < 16; i = i + 2)
    {
        tempVariable = (uint16_t)(data[i]);
        tempVariable = tempVariable | ((uint16_t)(data[i + 1]) << 8);
        HWREG16(baseAddress + OFS_AESADIN) = tempVariable;
    }

    // Key that is already written shall be used
    // Encryption is initialized by setting AESKEYWR to 1
    HWREG16(baseAddress + OFS_AESASTAT) |= AESKEYWR;

    // Wait unit finished ~167 MCLK
    while(AESBUSY == (HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY))
    {
        ;
    }

    // Write encrypted data back to variable
    for(i = 0; i < 16; i = i + 2)
    {
        tempData = HWREG16(baseAddress + OFS_AESADOUT);
        *(encryptedData + i) = (uint8_t)tempData;
        *(encryptedData + i + 1) = (uint8_t)(tempData >> 8);
    }
}

void AES256_decryptData(uint16_t baseAddress,
                        const uint8_t * data,
                        uint8_t * decryptedData)
{
    uint8_t i;
    uint16_t tempData = 0;
    uint16_t tempVariable = 0;

    // Set module to decrypt mode
    HWREG16(baseAddress + OFS_AESACTL0) |= (AESOP_3);

    // Write data to decrypt to module
    for(i = 0; i < 16; i = i + 2)
    {
        tempVariable = (uint16_t)(data[i + 1] << 8);
        tempVariable = tempVariable | ((uint16_t)(data[i]));
        HWREG16(baseAddress + OFS_AESADIN) = tempVariable;
    }

    // Key that is already written shall be used
    // Now decryption starts
    HWREG16(baseAddress + OFS_AESASTAT) |= AESKEYWR;

    // Wait unit finished ~167 MCLK
    while(AESBUSY == (HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY))
    {
        ;
    }

    // Write encrypted data back to variable
    for(i = 0; i < 16; i = i + 2)
    {
        tempData = HWREG16(baseAddress + OFS_AESADOUT);
        *(decryptedData + i) = (uint8_t)tempData;
        *(decryptedData + i + 1) = (uint8_t)(tempData >> 8);
    }
}

uint8_t AES256_setDecipherKey(uint16_t baseAddress,
                              const uint8_t * cipherKey,
                              uint16_t keyLength)
{
    uint8_t i;
    uint16_t tempVariable = 0;

    // Set module to decrypt mode
    HWREG16(baseAddress + OFS_AESACTL0) &= ~(AESOP0);
    HWREG16(baseAddress + OFS_AESACTL0) |= AESOP1;

    switch(keyLength)
    {
    case AES256_KEYLENGTH_128BIT:
        HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__128;
        break;

    case AES256_KEYLENGTH_192BIT:
        HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__192;
        break;

    case AES256_KEYLENGTH_256BIT:
        HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__256;
        break;

    default:
        return(STATUS_FAIL);
    }

    keyLength = keyLength / 8;

    // Write cipher key to key register
    for(i = 0; i < keyLength; i = i + 2)
    {
        tempVariable = (uint16_t)(cipherKey[i]);
        tempVariable = tempVariable | ((uint16_t)(cipherKey[i + 1]) << 8);
        HWREG16(baseAddress + OFS_AESAKEY) = tempVariable;
    }

    // Wait until key is processed ~52 MCLK
    while((HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY) == AESBUSY)
    {
        ;
    }

    return(STATUS_SUCCESS);
}

void AES256_clearInterrupt(uint16_t baseAddress)
{
    HWREG16(baseAddress + OFS_AESACTL0) &= ~AESRDYIFG;
}

uint32_t AES256_getInterruptStatus(uint16_t baseAddress)
{
    return ((HWREG16(baseAddress + OFS_AESACTL0) & AESRDYIFG) << 0x04);
}

void AES256_enableInterrupt(uint16_t baseAddress)
{
    HWREG16(baseAddress + OFS_AESACTL0) |= AESRDYIE;
}

void AES256_disableInterrupt(uint16_t baseAddress)
{
    HWREG16(baseAddress + OFS_AESACTL0) &= ~AESRDYIE;
}

void AES256_reset(uint16_t baseAddress)
{
    HWREG16(baseAddress + OFS_AESACTL0) |= AESSWRST;
}

void AES256_startEncryptData(uint16_t baseAddress,
                             const uint8_t * data)
{
    uint8_t i;
    uint16_t tempVariable = 0;

    // Set module to encrypt mode
    HWREG16(baseAddress + OFS_AESACTL0) &= ~AESOP_3;

    // Write data to encrypt to module
    for(i = 0; i < 16; i = i + 2)
    {
        tempVariable = (uint16_t)(data[i]);
        tempVariable = tempVariable | ((uint16_t)(data[i + 1 ]) << 8);
        HWREG16(baseAddress + OFS_AESADIN) = tempVariable;
    }

    // Key that is already written shall be used
    // Encryption is initialized by setting AESKEYWR to 1
    HWREG16(baseAddress + OFS_AESASTAT) |= AESKEYWR;
}

void AES256_startDecryptData(uint16_t baseAddress,
                             const uint8_t * data)
{
    uint8_t i;
    uint16_t tempVariable = 0;

    // Set module to decrypt mode
    HWREG16(baseAddress + OFS_AESACTL0) |= (AESOP_3);

    // Write data to decrypt to module
    for(i = 0; i < 16; i = i + 2)
    {
        tempVariable = (uint16_t)(data[i + 1] << 8);
        tempVariable = tempVariable | ((uint16_t)(data[i]));
        HWREG16(baseAddress + OFS_AESADIN) = tempVariable;
    }

    // Key that is already written shall be used
    // Now decryption starts
    HWREG16(baseAddress + OFS_AESASTAT) |= AESKEYWR;
}

uint8_t AES256_startSetDecipherKey(uint16_t baseAddress,
                                   const uint8_t * cipherKey,
                                   uint16_t keyLength)
{
    uint8_t i;
    uint16_t tempVariable = 0;

    HWREG16(baseAddress + OFS_AESACTL0) &= ~(AESOP0);
    HWREG16(baseAddress + OFS_AESACTL0) |= AESOP1;

    switch(keyLength)
    {
    case AES256_KEYLENGTH_128BIT:
        HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__128;
        break;

    case AES256_KEYLENGTH_192BIT:
        HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__192;
        break;

    case AES256_KEYLENGTH_256BIT:
        HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__256;
        break;

    default:
        return(STATUS_FAIL);
    }

    keyLength = keyLength / 8;

    // Write cipher key to key register
    for(i = 0; i < keyLength; i = i + 2)
    {
        tempVariable = (uint16_t)(cipherKey[i]);
        tempVariable = tempVariable | ((uint16_t)(cipherKey[i + 1]) << 8);
        HWREG16(baseAddress + OFS_AESAKEY) = tempVariable;
    }

    return(STATUS_SUCCESS);
}

uint8_t AES256_getDataOut(uint16_t baseAddress,
                          uint8_t *outputData)
{
    uint8_t i;
    uint16_t tempData = 0;

    // If module is busy, exit and return failure
    if(AESBUSY == (HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY))
    {
        return(STATUS_FAIL);
    }

    // Write encrypted data back to variable
    for(i = 0; i < 16; i = i + 2)
    {
        tempData = HWREG16(baseAddress + OFS_AESADOUT);
        *(outputData + i) = (uint8_t)tempData;
        *(outputData + i + 1) = (uint8_t)(tempData >> 8);
    }

    return(STATUS_SUCCESS);
}

uint16_t AES256_isBusy(uint16_t baseAddress)
{
    return (HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY);
}

void AES256_clearErrorFlag(uint16_t baseAddress)
{
    HWREG16(baseAddress + OFS_AESACTL0) &= ~AESERRFG;
}

uint32_t AES256_getErrorFlagStatus(uint16_t baseAddress)
{
    return (HWREG16(baseAddress + OFS_AESACTL0) & AESERRFG);
}

#endif
//*****************************************************************************
//
//! Close the doxygen group for aes256_api
//! @}
//
//*****************************************************************************