Overview

The MCUXpresso SDK provides a peripheral driver for the Secure Non-Volatile Storage Low-Power (SNVS-LP) module.

The SNVS_LP is a data storage subsystem. Its purpose is to store and protect system data, regardless of the main system power state. The SNVS _LP is in the always-powered-up domain, which is a separate power domain with its own power supply.

Data Structures
struct	snvs_lp_srtc_datetime_t
	Structure is used to hold the date and time. More...

struct	snvs_lp_srtc_config_t
	SNVS_LP config structure. More...

Macros
#define	SNVS_ZMK_REG_COUNT 8U /* 8 Zeroizable Master Key registers. */
	Define of SNVS_LP Zeroizable Master Key registers.

#define	SNVS_LP_MAX_TAMPER kSNVS_ExternalTamper1
	Define of SNVS_LP Max possible tamper.

Enumerations
enum	snvs_lp_srtc_interrupts_t { kSNVS_SRTC_AlarmInterrupt = SNVS_LPCR_LPTA_EN_MASK }
	List of SNVS_LP interrupts. More...

enum	snvs_lp_srtc_status_flags_t { kSNVS_SRTC_AlarmInterruptFlag = SNVS_LPSR_LPTA_MASK }
	List of SNVS_LP flags. More...

enum	snvs_lp_external_tamper_t
	List of SNVS_LP external tampers.

enum	snvs_lp_external_tamper_status_t
	List of SNVS_LP external tampers status.

enum	snvs_lp_external_tamper_polarity_t
	SNVS_LP external tamper polarity.

enum	snvs_lp_zmk_program_mode_t { kSNVS_ZMKSoftwareProgram, kSNVS_ZMKHardwareProgram }
	SNVS_LP Zeroizable Master Key programming mode. More...

enum	snvs_lp_master_key_mode_t { kSNVS_OTPMK = 0, kSNVS_ZMK = 2, kSNVS_CMK = 3 }
	SNVS_LP Master Key mode. More...

Functions
void	SNVS_LP_SRTC_Init (SNVS_Type base, const snvs_lp_srtc_config_t config)
	Ungates the SNVS clock and configures the peripheral for basic operation. More...

void	SNVS_LP_SRTC_Deinit (SNVS_Type *base)
	Stops the SRTC timer. More...

void	SNVS_LP_SRTC_GetDefaultConfig (snvs_lp_srtc_config_t *config)
	Fills in the SNVS_LP config struct with the default settings. More...

Driver version
#define	FSL_SNVS_LP_DRIVER_VERSION (MAKE_VERSION(2, 2, 0))
	Version 2.2.0.

Initialization and deinitialization
void	SNVS_LP_Init (SNVS_Type *base)
	Ungates the SNVS clock and configures the peripheral for basic operation. More...

void	SNVS_LP_Deinit (SNVS_Type *base)
	Deinit the SNVS LP section. More...

Secure RTC (SRTC) current Time & Alarm
status_t	SNVS_LP_SRTC_SetDatetime (SNVS_Type base, const snvs_lp_srtc_datetime_t datetime)
	Sets the SNVS SRTC date and time according to the given time structure. More...

void	SNVS_LP_SRTC_GetDatetime (SNVS_Type base, snvs_lp_srtc_datetime_t datetime)
	Gets the SNVS SRTC time and stores it in the given time structure. More...

status_t	SNVS_LP_SRTC_SetAlarm (SNVS_Type base, const snvs_lp_srtc_datetime_t alarmTime)
	Sets the SNVS SRTC alarm time. More...

void	SNVS_LP_SRTC_GetAlarm (SNVS_Type base, snvs_lp_srtc_datetime_t datetime)
	Returns the SNVS SRTC alarm time. More...

Interrupt Interface
static void	SNVS_LP_SRTC_EnableInterrupts (SNVS_Type *base, uint32_t mask)
	Enables the selected SNVS interrupts. More...

static void	SNVS_LP_SRTC_DisableInterrupts (SNVS_Type *base, uint32_t mask)
	Disables the selected SNVS interrupts. More...

uint32_t	SNVS_LP_SRTC_GetEnabledInterrupts (SNVS_Type *base)
	Gets the enabled SNVS interrupts. More...

Status Interface
uint32_t	SNVS_LP_SRTC_GetStatusFlags (SNVS_Type *base)
	Gets the SNVS status flags. More...

static void	SNVS_LP_SRTC_ClearStatusFlags (SNVS_Type *base, uint32_t mask)
	Clears the SNVS status flags. More...

Timer Start and Stop
static void	SNVS_LP_SRTC_StartTimer (SNVS_Type *base)
	Starts the SNVS SRTC time counter. More...

static void	SNVS_LP_SRTC_StopTimer (SNVS_Type *base)
	Stops the SNVS SRTC time counter. More...

External tampering
void	SNVS_LP_EnableExternalTamper (SNVS_Type *base, snvs_lp_external_tamper_t pin, snvs_lp_external_tamper_polarity_t polarity)
	Enables the specified SNVS external tamper. More...

void	SNVS_LP_DisableExternalTamper (SNVS_Type *base, snvs_lp_external_tamper_t pin)
	Disables the specified SNVS external tamper. More...

snvs_lp_external_tamper_status_t	SNVS_LP_GetExternalTamperStatus (SNVS_Type *base, snvs_lp_external_tamper_t pin)
	Returns status of the specified external tamper. More...

void	SNVS_LP_ClearExternalTamperStatus (SNVS_Type *base, snvs_lp_external_tamper_t pin)
	Clears status of the specified external tamper. More...

Monotonic Counter (MC)
static void	SNVS_LP_EnableMonotonicCounter (SNVS_Type *base, bool enable)
	Enable or disable the Monotonic Counter. More...

uint64_t	SNVS_LP_GetMonotonicCounter (SNVS_Type *base)
	Get the current Monotonic Counter. More...

static void	SNVS_LP_IncreaseMonotonicCounter (SNVS_Type *base)
	Increase the Monotonic Counter. More...

Zeroizable Master Key (ZMK)
void	SNVS_LP_WriteZeroizableMasterKey (SNVS_Type *base, uint32_t ZMKey[SNVS_ZMK_REG_COUNT])
	Write Zeroizable Master Key (ZMK) to the SNVS registers. More...

static void	SNVS_LP_SetZeroizableMasterKeyValid (SNVS_Type *base, bool valid)
	Set Zeroizable Master Key valid. More...

static bool	SNVS_LP_GetZeroizableMasterKeyValid (SNVS_Type *base)
	Get Zeroizable Master Key valid status. More...

static void	SNVS_LP_SetZeroizableMasterKeyProgramMode (SNVS_Type *base, snvs_lp_zmk_program_mode_t mode)
	Set Zeroizable Master Key programming mode. More...

static void	SNVS_LP_EnableZeroizableMasterKeyECC (SNVS_Type *base, bool enable)
	Enable or disable Zeroizable Master Key ECC. More...

static void	SNVS_LP_SetMasterKeyMode (SNVS_Type *base, snvs_lp_master_key_mode_t mode)
	Set SNVS Master Key mode. More...

Data Structure Documentation

struct snvs_lp_srtc_datetime_t

Data Fields
uint16_t	year
	Range from 1970 to 2099. More...

uint8_t	month
	Range from 1 to 12. More...

uint8_t	day
	Range from 1 to 31 (depending on month). More...

uint8_t	hour
	Range from 0 to 23. More...

uint8_t	minute
	Range from 0 to 59. More...

uint8_t	second
	Range from 0 to 59. More...

Field Documentation

uint16_t snvs_lp_srtc_datetime_t::year

uint8_t snvs_lp_srtc_datetime_t::month

uint8_t snvs_lp_srtc_datetime_t::day

uint8_t snvs_lp_srtc_datetime_t::hour

uint8_t snvs_lp_srtc_datetime_t::minute

uint8_t snvs_lp_srtc_datetime_t::second

struct snvs_lp_srtc_config_t

This structure holds the configuration settings for the SNVS_LP peripheral. To initialize this structure to reasonable defaults, call the SNVS_LP_GetDefaultConfig() function and pass a pointer to your config structure instance.

The config struct can be made const so it resides in flash

Data Fields
bool	srtcCalEnable
	true: SRTC calibration mechanism is enabled; false: No calibration is used

uint32_t	srtcCalValue
	Defines signed calibration value for SRTC; This is a 5-bit 2's complement value, range from -16 to +15.

Enumeration Type Documentation

enum snvs_lp_srtc_interrupts_t

Enumerator
kSNVS_SRTC_AlarmInterrupt	SRTC time alarm.

enum snvs_lp_srtc_status_flags_t

Enumerator
kSNVS_SRTC_AlarmInterruptFlag	SRTC time alarm flag.

enum snvs_lp_zmk_program_mode_t

Enumerator
kSNVS_ZMKSoftwareProgram	Software programming mode.
kSNVS_ZMKHardwareProgram	Hardware programming mode.

enum snvs_lp_master_key_mode_t

Enumerator
kSNVS_OTPMK	One Time Programmable Master Key.
kSNVS_ZMK	Zeroizable Master Key.
kSNVS_CMK	Combined Master Key, it is XOR of OPTMK and ZMK.

Function Documentation

void SNVS_LP_Init ( SNVS_Type * base )

Note: This API should be called at the beginning of the application using the SNVS driver.

Parameters

base	SNVS peripheral base address

void SNVS_LP_Deinit ( SNVS_Type * base )

Parameters

base	SNVS peripheral base address

void SNVS_LP_SRTC_Init	(	SNVS_Type *	base,
		const snvs_lp_srtc_config_t *	config
	)

Note: This API should be called at the beginning of the application using the SNVS driver.

Parameters

base	SNVS peripheral base address
config	Pointer to the user's SNVS configuration structure.

void SNVS_LP_SRTC_Deinit ( SNVS_Type * base )

Parameters

base	SNVS peripheral base address

void SNVS_LP_SRTC_GetDefaultConfig ( snvs_lp_srtc_config_t * config )

The default values are as follows.

*    config->srtccalenable = false;
*    config->srtccalvalue = 0U;
* 

Parameters

config Pointer to the user's SNVS configuration structure.

status_t SNVS_LP_SRTC_SetDatetime	(	SNVS_Type *	base,
		const snvs_lp_srtc_datetime_t *	datetime
	)

Parameters

base	SNVS peripheral base address
datetime	Pointer to the structure where the date and time details are stored.

Returns: kStatus_Success: Success in setting the time and starting the SNVS SRTC kStatus_InvalidArgument: Error because the datetime format is incorrect

void SNVS_LP_SRTC_GetDatetime	(	SNVS_Type *	base,
		snvs_lp_srtc_datetime_t *	datetime
	)

Parameters

base	SNVS peripheral base address
datetime	Pointer to the structure where the date and time details are stored.

status_t SNVS_LP_SRTC_SetAlarm	(	SNVS_Type *	base,
		const snvs_lp_srtc_datetime_t *	alarmTime
	)

The function sets the SRTC alarm. It also checks whether the specified alarm time is greater than the present time. If not, the function does not set the alarm and returns an error. Please note, that SRTC alarm has limited resolution because only 32 most significant bits of SRTC counter are compared to SRTC Alarm register. If the alarm time is beyond SRTC resolution, the function does not set the alarm and returns an error.

Parameters

base	SNVS peripheral base address
alarmTime	Pointer to the structure where the alarm time is stored.

Returns: kStatus_Success: success in setting the SNVS SRTC alarm kStatus_InvalidArgument: Error because the alarm datetime format is incorrect kStatus_Fail: Error because the alarm time has already passed or is beyond resolution

void SNVS_LP_SRTC_GetAlarm	(	SNVS_Type *	base,
		snvs_lp_srtc_datetime_t *	datetime
	)

Parameters

base	SNVS peripheral base address
datetime	Pointer to the structure where the alarm date and time details are stored.

static void SNVS_LP_SRTC_EnableInterrupts	(	SNVS_Type *	base,
		uint32_t	mask
	)

inlinestatic

Parameters

base	SNVS peripheral base address
mask	The interrupts to enable. This is a logical OR of members of the enumeration :: _snvs_lp_srtc_interrupts

static void SNVS_LP_SRTC_DisableInterrupts	(	SNVS_Type *	base,
		uint32_t	mask
	)

inlinestatic

Parameters

base	SNVS peripheral base address
mask	The interrupts to enable. This is a logical OR of members of the enumeration :: _snvs_lp_srtc_interrupts

uint32_t SNVS_LP_SRTC_GetEnabledInterrupts ( SNVS_Type * base )

Parameters

base	SNVS peripheral base address

Returns: The enabled interrupts. This is the logical OR of members of the enumeration :: _snvs_lp_srtc_interrupts

uint32_t SNVS_LP_SRTC_GetStatusFlags ( SNVS_Type * base )

Parameters

base	SNVS peripheral base address

Returns: The status flags. This is the logical OR of members of the enumeration :: _snvs_lp_srtc_status_flags

static void SNVS_LP_SRTC_ClearStatusFlags	(	SNVS_Type *	base,
		uint32_t	mask
	)

inlinestatic

Parameters

base	SNVS peripheral base address
mask	The status flags to clear. This is a logical OR of members of the enumeration :: _snvs_lp_srtc_status_flags

static void SNVS_LP_SRTC_StartTimer ( SNVS_Type * base )

inlinestatic

Parameters

base	SNVS peripheral base address

static void SNVS_LP_SRTC_StopTimer ( SNVS_Type * base )

inlinestatic

Parameters

base	SNVS peripheral base address

void SNVS_LP_EnableExternalTamper	(	SNVS_Type *	base,
		snvs_lp_external_tamper_t	pin,
		snvs_lp_external_tamper_polarity_t	polarity
	)

Parameters

base	SNVS peripheral base address
pin	SNVS external tamper pin
polarity	Polarity of external tamper

void SNVS_LP_DisableExternalTamper	(	SNVS_Type *	base,
		snvs_lp_external_tamper_t	pin
	)

Parameters

base	SNVS peripheral base address
pin	SNVS external tamper pin

snvs_lp_external_tamper_status_t SNVS_LP_GetExternalTamperStatus	(	SNVS_Type *	base,
		snvs_lp_external_tamper_t	pin
	)

Parameters

base	SNVS peripheral base address
pin	SNVS external tamper pin

Returns: The status flag. This is the enumeration :: _snvs_lp_external_tamper_status

void SNVS_LP_ClearExternalTamperStatus	(	SNVS_Type *	base,
		snvs_lp_external_tamper_t	pin
	)

Parameters

base	SNVS peripheral base address
pin	SNVS external tamper pin

static void SNVS_LP_EnableMonotonicCounter	(	SNVS_Type *	base,
		bool	enable
	)

inlinestatic

Parameters

base	SNVS peripheral base address
enable	Pass true to enable, false to disable.

uint64_t SNVS_LP_GetMonotonicCounter ( SNVS_Type * base )

Parameters

base	SNVS peripheral base address

Returns: Current Monotonic Counter value.

static void SNVS_LP_IncreaseMonotonicCounter ( SNVS_Type * base )

inlinestatic

Increase the Monotonic Counter by 1.

Parameters

base	SNVS peripheral base address

void SNVS_LP_WriteZeroizableMasterKey	(	SNVS_Type *	base,
		uint32_t	ZMKey[SNVS_ZMK_REG_COUNT]
	)

Parameters

base	SNVS peripheral base address
ZMKey	The ZMK write to the SNVS register.

static void SNVS_LP_SetZeroizableMasterKeyValid	(	SNVS_Type *	base,
		bool	valid
	)

inlinestatic

This API could only be called when using software programming mode. After writing ZMK using SNVS_LP_WriteZeroizableMasterKey, call this API to make the ZMK valid.

Parameters

base	SNVS peripheral base address
valid	Pass true to set valid, false to set invalid.

static bool SNVS_LP_GetZeroizableMasterKeyValid ( SNVS_Type * base )

inlinestatic

In hardware programming mode, call this API to check whether the ZMK is valid.

Parameters

base	SNVS peripheral base address

Returns: true if valid, false if invalid.

static void SNVS_LP_SetZeroizableMasterKeyProgramMode	(	SNVS_Type *	base,
		snvs_lp_zmk_program_mode_t	mode
	)

inlinestatic

Parameters

base	SNVS peripheral base address
mode	ZMK programming mode.

static void SNVS_LP_EnableZeroizableMasterKeyECC	(	SNVS_Type *	base,
		bool	enable
	)

inlinestatic

Parameters

base	SNVS peripheral base address
enable	Pass true to enable, false to disable.

static void SNVS_LP_SetMasterKeyMode	(	SNVS_Type *	base,
		snvs_lp_master_key_mode_t	mode
	)

inlinestatic

Parameters

base	SNVS peripheral base address
mode	Master Key mode.

Note: When kSNVS_ZMK or kSNVS_CMK used, the SNVS_HP must be configured to enable the master key selection.

Overview

Data Structures

Macros

Enumerations

Functions

Driver version

Initialization and deinitialization

Secure RTC (SRTC) current Time & Alarm

Interrupt Interface

Status Interface

Timer Start and Stop

External tampering

Monotonic Counter (MC)

Zeroizable Master Key (ZMK)

Data Structure Documentation

Data Fields

Field Documentation

Data Fields

Enumeration Type Documentation

Function Documentation