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/** \addtogroup icm_module Working with ICM
* \ingroup peripherals_module
* The TWI driver provides the interface to True Random Number Generator (ICM)
* passes the American NIST Special Publication 800-22 and Die-hard
* Random Tests Suites.
* The ICM may be used as an entropy source for seeding an NIST approved DRNG
* (Deterministic RNG) as required by FIPS PUB 140-2 and 140-3. use the TWI
* peripheral.
*
* \section Usage
* <ul>
* <li> Configures a TWI peripheral to operate in master mode, at the given
* frequency (in Hz) using TWI_Configure(). </li>
* <li> Sends a STOP condition on the TWI using TWI_Stop().</li>
* <li> Starts a read operation on the TWI bus with the specified slave using
* TWI_StartRead(). Data must then be read using TWI_ReadByte() whenever
* a byte is available (poll using TWI_ByteReceived()).</li>
* <li> Starts a write operation on the TWI to access the selected slave using
* TWI_StartWrite(). A byte of data must be provided to start the write;
* other bytes are written next.</li>
* <li> Sends a byte of data to one of the TWI slaves on the bus using
* TWI_WriteByte().
* This function must be called once before TWI_StartWrite() with the first byte
* of data to send, then it ICMll be called repeatedly after that to send the
* remaining bytes.</li>
* <li> Check if a byte has been received and can be read on the given TWI
* peripheral using TWI_ByteReceived().<
* Check if a byte has been sent using TWI_ByteSent().</li>
* <li> Check if the current transmission is complete (the STOP has been sent)
* using TWI_TransferComplete().</li>
* <li> Enables & disable the selected interrupts sources on a TWI peripheral
* using TWI_EnableIt() and TWI_DisableIt().</li>
* <li> Get current status register of the given TWI peripheral using
* TWI_GetStatus(). Get current status register of the given TWI peripheral, but
* masking interrupt sources which are not currently enabled using
* TWI_GetMaskedStatus().</li>
* </ul>
* For more accurate information, please look at the TWI section of the
* Datasheet.
*
* Related files :\n
* \ref twi.c\n
* \ref twi.h.\n
*/
/*@{*/
/*@}*/
/**
* \file
*
* Implementation of True Random Number Generator (ICM)
*
*/
/*----------------------------------------------------------------------------
* Headers
*----------------------------------------------------------------------------*/
#include "chip.h"
/*----------------------------------------------------------------------------
* Exported functions
*----------------------------------------------------------------------------*/
/**
* \brief Enable ICM, the ICM controller is activated
*/
void ICM_Enable(void)
{
ICM->ICM_CTRL = ICM_CTRL_ENABLE;
}
/**
* \brief Disable ICM, if a region is active, this region is terminated
*/
void ICM_Disable(void)
{
ICM->ICM_CTRL = ICM_CTRL_DISABLE;
}
/**
* \brief Resets the ICM controller.
*/
void ICM_SoftReset(void)
{
ICM->ICM_CTRL = ICM_CTRL_SWRST;
}
/**
* \brief Recompute Internal hash.
* \param region, When REHASH[region] is set to one, the region digest is
* re-computed.
* \note This bit is only available when Region monitoring is disabled.
*/
void ICM_ReComputeHash(uint8_t region)
{
ICM->ICM_CTRL = ICM_CTRL_REHASH(region);
}
/**
* \brief Enable region monitoring for given region
* \param region, When bit RMEN[region] is set to one, the monitoring of Region
* is activated.
*/
void ICM_EnableMonitor(uint8_t region)
{
ICM->ICM_CTRL = ICM_CTRL_RMEN(region);
}
/**
* \brief Disable region monitoring for given region
* \param region, When bit RMDIS[region] is set to one, the monitoring of
* Region is disabled.
*/
void ICM_DisableMonitor(uint8_t region)
{
ICM->ICM_CTRL = ICM_CTRL_RMDIS(region);
}
/**
* \brief Configures an ICM peripheral with the specified parameters.
* \param mode Desired value for the ICM mode register (see the datasheet).
*/
void ICM_Configure(uint32_t mode)
{
ICM->ICM_CFG = mode;
}
/**
* \brief Enables the selected interrupts sources on a ICM peripheral.
* \param sources Bitwise OR of selected interrupt sources.
*/
void ICM_EnableIt(uint32_t sources)
{
ICM->ICM_IER = sources;
}
/**
* \brief Disables the selected interrupts sources on a ICM peripheral.
* \param sources Bitwise OR of selected interrupt sources.
*/
void ICM_DisableIt(uint32_t sources)
{
ICM->ICM_IDR = sources;
}
/**
* \brief Get the current interrupt status register of the given ICM peripheral.
* \return ICM status register.
*/
uint32_t ICM_GetIntStatus(void)
{
return ICM->ICM_ISR;
}
/**
* \brief Get the current status register of the given ICM peripheral.
* \return ICM status register.
*/
uint32_t ICM_GetStatus(void)
{
return ICM->ICM_SR;
}
/**
* \brief Get the undefined access status register of the given ICM peripheral.
* \return ICM status register.
*/
uint32_t ICM_GetUStatus(void)
{
return ICM->ICM_UASR;
}
/**
* \brief Set descriptor area start address register.
* \param addr start address
* \note The start address is a multiple of the total size of the data structure
* (64 bytes).
*/
void ICM_SetDescStartAddress(uint32_t addr)
{
ICM->ICM_DSCR = addr;
}
/**
* \brief Set hash area start address register.
* \param addr start address
* \note This field points at the Hash memory location. The address must be a
* multiple of 128 bytes.
*/
void ICM_SetHashStartAddress(uint32_t addr)
{
ICM->ICM_HASH = addr;
}
/**
* \brief Set ICM user initial Hash value register.
* \param val Initial Hash Value
*/
void ICM_SetInitHashValue(uint32_t val)
{
ICM->ICM_UIHVAL[0] = ICM_UIHVAL_VAL(val);
}
