Overview

Data Structures
struct	XScuWdt_Config
	This typedef contains configuration information for the device. More...
struct	XScuWdt
	The XScuWdt driver instance data. More...

Macros
#define	XSCUWDT_H
	< prevent circular inclusions More...
#define	XScuWdt_IsWdtExpired(InstancePtr)
	This function is used to check if the watchdog has timed-out and the last reset was caused by the watchdog reset. More...
#define	XScuWdt_IsTimerExpired(InstancePtr)
	This function is used to check if the watchdog counter has reached 0 in timer mode. More...
#define	XScuWdt_RestartWdt(InstancePtr)
	Re-start the watchdog timer. More...
#define	XScuWdt_LoadWdt(InstancePtr, Value)
	Write to the watchdog timer load register. More...
#define	XScuWdt_SetWdMode(InstancePtr)
	Put the watchdog timer in Watchdog mode by setting the WD mode bit of the Watchdog control register. More...
#define	XScuWdt_SetTimerMode(InstancePtr)
	Put the watchdog timer in Timer mode by writing 0x12345678 and 0x87654321 successively to the Watchdog Disable Register. More...
#define	XScuWdt_GetControlReg(InstancePtr)
	Get the contents of the watchdog control register. More...
#define	XScuWdt_SetControlReg(InstancePtr, ControlReg)
	Write to the watchdog control register. More...
#define	XScuWdt_EnableAutoReload(InstancePtr)
	Enable auto-reload mode. More...
#define	XSCUWDT_HW_H
	< prevent circular inclusions More...
#define	XScuWdt_ReadReg(BaseAddr, RegOffset)   Xil_In32((BaseAddr) + ((u32)RegOffset))
	Read the given register. More...
#define	XScuWdt_WriteReg(BaseAddr, RegOffset, Data)   Xil_Out32((BaseAddr) + ((u32)RegOffset), ((u32)Data))
	Write the given register. More...

Functions
s32	XScuWdt_CfgInitialize (XScuWdt *InstancePtr, XScuWdt_Config *ConfigPtr, u32 EffectiveAddress)
	Initialize a specific watchdog timer instance/driver. More...
void	XScuWdt_Start (XScuWdt *InstancePtr)
	Start the watchdog counter of the device. More...
void	XScuWdt_Stop (XScuWdt *InstancePtr)
	Stop the watchdog timer. More...
XScuWdt_Config *	XScuWdt_LookupConfig (u16 DeviceId)
	Lookup the device configuration based on the unique device ID. More...
s32	XScuWdt_SelfTest (XScuWdt *InstancePtr)
	Run a self-test on the WDT. More...

Variables
XScuWdt_Config	XScuWdt_ConfigTable []
	This table contains configuration information for each watchdog timer device in the system. More...
XScuWdt_Config	XScuWdt_ConfigTable [XPAR_XSCUWDT_NUM_INSTANCES]
	This table contains configuration information for each watchdog timer device in the system. More...

Register Map
Offsets of registers from the start of the device. The WDT registers start at an offset 0x20
#define	XSCUWDT_LOAD_OFFSET   0x00U
	Watchdog Load Register. More...
#define	XSCUWDT_COUNTER_OFFSET   0x04U
	Watchdog Counter Register. More...
#define	XSCUWDT_CONTROL_OFFSET   0x08U
	Watchdog Control Register. More...
#define	XSCUWDT_ISR_OFFSET   0x0CU
	Watchdog Interrupt Status Register. More...
#define	XSCUWDT_RST_STS_OFFSET   0x10U
	Watchdog Reset Status Register. More...
#define	XSCUWDT_DISABLE_OFFSET   0x14U
	Watchdog Disable Register. More...

Watchdog Control register
This register bits control the prescaler, WD/Timer mode, Intr enable, auto-reload, watchdog enable.
#define	XSCUWDT_CONTROL_PRESCALER_MASK   0x0000FF00U
	Prescaler. More...
#define	XSCUWDT_CONTROL_PRESCALER_SHIFT   8U
#define	XSCUWDT_CONTROL_WD_MODE_MASK   0x00000008U
	Watchdog/Timer mode. More...
#define	XSCUWDT_CONTROL_IT_ENABLE_MASK   0x00000004U
	Intr enable (in timer mode) More...
#define	XSCUWDT_CONTROL_AUTO_RELOAD_MASK   0x00000002U
	Auto-reload (in timer mode) More...
#define	XSCUWDT_CONTROL_WD_ENABLE_MASK   0x00000001U
	Watchdog enable. More...

Interrupt Status register
This register indicates the Counter register has reached zero in Counter mode.
#define	XSCUWDT_ISR_EVENT_FLAG_MASK   0x00000001U
	Event flag. More...

Reset Status register
This register indicates the Counter register has reached zero in Watchdog mode and a reset request is sent.
#define	XSCUWDT_RST_STS_RESET_FLAG_MASK   0x00000001U
	Time out occurred. More...

Disable register
This register is used to switch from watchdog mode to timer mode. The software must write 0x12345678 and 0x87654321 successively to the Watchdog Disable Register so that the watchdog mode bit in the Watchdog Control Register is set to zero.
#define	XSCUWDT_DISABLE_VALUE1   0x12345678U
	Watchdog mode disable value 1. More...
#define	XSCUWDT_DISABLE_VALUE2   0x87654321U
	Watchdog mode disable value 2. More...

Macro Definition Documentation

#define XSCUWDT_CONTROL_AUTO_RELOAD_MASK   0x00000002U

Auto-reload (in timer mode)

#define XSCUWDT_CONTROL_IT_ENABLE_MASK   0x00000004U

Intr enable (in timer mode)

Referenced by ScuWdtIntrExample().

#define XSCUWDT_CONTROL_OFFSET   0x08U

Watchdog Control Register.

Referenced by XScuWdt_Start(), and XScuWdt_Stop().

#define XSCUWDT_CONTROL_PRESCALER_MASK   0x0000FF00U

Prescaler.

#define XSCUWDT_CONTROL_WD_ENABLE_MASK   0x00000001U

Watchdog enable.

Referenced by XScuWdt_SelfTest(), XScuWdt_Start(), and XScuWdt_Stop().

#define XSCUWDT_CONTROL_WD_MODE_MASK   0x00000008U

Watchdog/Timer mode.

#define XSCUWDT_COUNTER_OFFSET   0x04U

Watchdog Counter Register.

Referenced by XScuWdt_SelfTest().

#define XSCUWDT_DISABLE_OFFSET   0x14U

Watchdog Disable Register.

#define XSCUWDT_DISABLE_VALUE1   0x12345678U

Watchdog mode disable value 1.

#define XSCUWDT_DISABLE_VALUE2   0x87654321U

Watchdog mode disable value 2.

#define XScuWdt_EnableAutoReload

(

InstancePtr

)

Value:

XScuWdt_SetControlReg((InstancePtr),                            \
                              (XScuWdt_GetControlReg(InstancePtr) |     \
                               XSCUWDT_CONTROL_AUTO_RELOAD_MASK))

Enable auto-reload mode.

Parameters

InstancePtr

is a pointer to the XScuWdt instance.

Returns

None.

Note

C-style signature: void XScuWdt_EnableAutoReload(XScuWdt *InstancePtr)

#define XScuWdt_GetControlReg

(

InstancePtr

)

Value:

XScuWdt_ReadReg((InstancePtr)->Config.BaseAddr,                 \
                        XSCUWDT_CONTROL_OFFSET)

Get the contents of the watchdog control register.

Parameters

InstancePtr

is a pointer to the XScuWdt instance.

Returns

Contents of the watchdog control register.

Note

C-style signature: u32 XScuWdt_GetControlReg(XScuWdt *InstancePtr)

Referenced by ScuWdtIntrExample(), and XScuWdt_SelfTest().

#define XSCUWDT_H

< prevent circular inclusions

by using protection macros

#define XSCUWDT_HW_H

< prevent circular inclusions

by using protection macros

#define XSCUWDT_ISR_EVENT_FLAG_MASK   0x00000001U

Event flag.

Referenced by ScuWdtIntrExample().

#define XSCUWDT_ISR_OFFSET   0x0CU

Watchdog Interrupt Status Register.

Referenced by ScuWdtIntrExample().

#define XScuWdt_IsTimerExpired

(

InstancePtr

)

Value:

((XScuWdt_ReadReg((InstancePtr)->Config.BaseAddr,               \
                          XSCUWDT_ISR_OFFSET) &                         \
	  XSCUWDT_ISR_EVENT_FLAG_MASK) == XSCUWDT_ISR_EVENT_FLAG_MASK)

This function is used to check if the watchdog counter has reached 0 in timer mode.

Parameters

InstancePtr

is a pointer to the XScuWdt instance.

Returns

• TRUE if the watchdog has expired.
• FALSE if the watchdog has not expired.

Note

C-style signature: int XScuWdt_IsTimerExpired(XScuWdt *InstancePtr)

Referenced by ScuWdtIntrExample().

#define XScuWdt_IsWdtExpired

(

InstancePtr

)

Value:

((XScuWdt_ReadReg((InstancePtr)->Config.BaseAddr,               \
                          XSCUWDT_RST_STS_OFFSET) &                     \
	  XSCUWDT_RST_STS_RESET_FLAG_MASK) == XSCUWDT_RST_STS_RESET_FLAG_MASK)

This function is used to check if the watchdog has timed-out and the last reset was caused by the watchdog reset.

Parameters

InstancePtr

is a pointer to the XScuWdt instance.

Returns

• TRUE if the watchdog has expired.
• FALSE if the watchdog has not expired.

Note

C-style signature: int XScuWdt_IsWdtExpired(XScuWdt *InstancePtr)

#define XSCUWDT_LOAD_OFFSET   0x00U

Watchdog Load Register.

Referenced by XScuWdt_SelfTest().

#define XScuWdt_LoadWdt	(		InstancePtr,
			Value
	)

Value:

XScuWdt_WriteReg((InstancePtr)->Config.BaseAddr,                \
                         XSCUWDT_LOAD_OFFSET, (Value))

Write to the watchdog timer load register.

This will also update the watchdog counter register with the new value. This macro can be used to change the time-out value.

Parameters

InstancePtr	is a pointer to the XScuWdt instance.
Value	is the value to be written to the Watchdog Load register.

Returns

None.

Note

C-style signature: void XScuWdt_LoadWdt(XScuWdt *InstancePtr, u32 Value)

Referenced by ScuWdtIntrExample(), ScuWdtPolledExample(), and XScuWdt_SelfTest().

#define XScuWdt_ReadReg	(		BaseAddr,
			RegOffset
	)		Xil_In32((BaseAddr) + ((u32)RegOffset))

Read the given register.

Parameters

BaseAddr	is the base address of the device
RegOffset	is the register offset to be read

Returns

The 32-bit value of the register

Note

C-style signature: u32 XScuWdt_ReadReg(u32 BaseAddr, u32 RegOffset)

Referenced by XScuWdt_SelfTest(), XScuWdt_Start(), and XScuWdt_Stop().

#define XScuWdt_RestartWdt

(

InstancePtr

)

Value:

XScuWdt_LoadWdt((InstancePtr),                                   \
                        (XScuWdt_ReadReg((InstancePtr)->Config.BaseAddr, \
                                         XSCUWDT_LOAD_OFFSET)))

Re-start the watchdog timer.

This macro will read the watchdog load register and write the same value to load register to update the counter register. An application needs to call this function periodically to keep the watchdog from asserting the WDRESETREQ reset request output pin.

Parameters

InstancePtr

is a pointer to the XScuWdt instance.

Returns

None.

Note

C-style signature: void XScuWdt_RestartWdt(XScuWdt *InstancePtr)

Referenced by ScuWdtIntrExample(), and ScuWdtPolledExample().

#define XSCUWDT_RST_STS_OFFSET   0x10U

Watchdog Reset Status Register.

#define XSCUWDT_RST_STS_RESET_FLAG_MASK   0x00000001U

Time out occurred.

#define XScuWdt_SetControlReg	(		InstancePtr,
			ControlReg
	)

Value:

XScuWdt_WriteReg((InstancePtr)->Config.BaseAddr,                \
                         XSCUWDT_CONTROL_OFFSET, (ControlReg))

Write to the watchdog control register.

Parameters

InstancePtr	is a pointer to the XScuWdt instance.
ControlReg	is the value to be written to the watchdog control register.

Returns

None.

Note

C-style signature: void XScuWdt_SetControlReg(XScuWdt *InstancePtr, u32 ControlReg)

Referenced by ScuWdtIntrExample(), and XScuWdt_SelfTest().

#define XScuWdt_SetTimerMode

(

InstancePtr

)

Value:

{                                                                       \
		XScuWdt_WriteReg((InstancePtr)->Config.BaseAddr,              \
                                 XSCUWDT_DISABLE_OFFSET,                                \
                                 XSCUWDT_DISABLE_VALUE1);                       \
		XScuWdt_WriteReg((InstancePtr)->Config.BaseAddr,              \
                                 XSCUWDT_DISABLE_OFFSET,                                \
                                 XSCUWDT_DISABLE_VALUE2);                       \
        }

Put the watchdog timer in Timer mode by writing 0x12345678 and 0x87654321 successively to the Watchdog Disable Register.

The software must write 0x12345678 and 0x87654321 successively to the Watchdog Disable Register so that the watchdog mode bit in the Watchdog Control Register is set to zero.

Parameters

InstancePtr

is a pointer to the XScuWdt instance.

Returns

None.

Note

C-style signature: void XScuWdt_SetTimerMode(XScuWdt *InstancePtr)

Referenced by ScuWdtIntrExample().

#define XScuWdt_SetWdMode

(

InstancePtr

)

Value:

XScuWdt_WriteReg((InstancePtr)->Config.BaseAddr,                  \
                         XSCUWDT_CONTROL_OFFSET,                          \
                         (XScuWdt_ReadReg((InstancePtr)->Config.BaseAddr, \
                                          XSCUWDT_CONTROL_OFFSET) |                       \
                          (XSCUWDT_CONTROL_WD_MODE_MASK)))

Put the watchdog timer in Watchdog mode by setting the WD mode bit of the Watchdog control register.

Parameters

InstancePtr

is a pointer to the XScuWdt instance.

Returns

None.

Note

C-style signature: void XScuWdt_SetWdMode(XScuWdt *InstancePtr)

Referenced by ScuWdtPolledExample(), and XScuWdt_CfgInitialize().

#define XScuWdt_WriteReg	(		BaseAddr,
			RegOffset,
			Data
	)		Xil_Out32((BaseAddr) + ((u32)RegOffset), ((u32)Data))

Write the given register.

Parameters

BaseAddr	is the base address of the device
RegOffset	is the register offset to be written
Data	is the 32-bit value to write to the register

Returns

None.

Note

C-style signature: void XScuWdt_WriteReg(u32 BaseAddr, u32 RegOffset, u32 Data)

Referenced by ScuWdtIntrExample(), XScuWdt_Start(), and XScuWdt_Stop().

Function Documentation

s32 XScuWdt_CfgInitialize	(	XScuWdt *	InstancePtr,
		XScuWdt_Config *	ConfigPtr,
		u32	EffectiveAddress
	)

Initialize a specific watchdog timer instance/driver.

This function must be called before other functions of the driver are called.

Parameters

InstancePtr	is a pointer to the XScuWdt instance.
ConfigPtr	is the config structure.
EffectiveAddress	is the base address for the device. It could be a virtual address if address translation is supported in the system, otherwise it is the physical address.

Returns

• XST_SUCCESS if initialization was successful.
• XST_DEVICE_IS_STARTED if the device has already been started.

Note

This function enables the watchdog mode.

References XScuWdt_Config::BaseAddr, XScuWdt::Config, XScuWdt_Config::DeviceId, XScuWdt::IsReady, XScuWdt::IsStarted, and XScuWdt_SetWdMode.

Referenced by ScuWdtIntrExample(), and ScuWdtPolledExample().

XScuWdt_Config * XScuWdt_LookupConfig

(

u16

DeviceId

)

Lookup the device configuration based on the unique device ID.

The table contains the configuration info for each device in the system.

Parameters

DeviceId

is the unique device ID of the device being looked up.

Returns

A pointer to the configuration table entry corresponding to the given device ID, or NULL if no match is found.

Note

None.

References XScuWdt_ConfigTable.

Referenced by ScuWdtIntrExample(), and ScuWdtPolledExample().

s32 XScuWdt_SelfTest

(

XScuWdt *

InstancePtr

)

Run a self-test on the WDT.

This test stops the watchdog, writes a value to the watchdog load register, starts the watchdog and verifies that the value read from the counter register is less that the value written to the load register. It then restores the control register and the watchdog load register.

Parameters

InstancePtr

is a pointer to the XScuWdt instance.

Returns

• XST_SUCCESS if self-test was successful.
• XST_FAILURE if the WDT is not decrementing.

Note

None.

References XScuWdt::IsReady, XSCUWDT_CONTROL_WD_ENABLE_MASK, XSCUWDT_COUNTER_OFFSET, XScuWdt_GetControlReg, XSCUWDT_LOAD_OFFSET, XScuWdt_LoadWdt, XScuWdt_ReadReg, and XScuWdt_SetControlReg.

Referenced by ScuWdtIntrExample().

void XScuWdt_Start

(

XScuWdt *

InstancePtr

)

Start the watchdog counter of the device.

Parameters

InstancePtr

is a pointer to the XScuWdt instance.

Returns

None.

Note

User needs to select the appropriate mode (watchdog/timer) before using this API. See XScuWdt_SetWdMode/XScuWdt_SetTimerMode macros in xscuwdt.h.

References XScuWdt_Config::BaseAddr, XScuWdt::Config, XScuWdt::IsReady, XScuWdt::IsStarted, XSCUWDT_CONTROL_OFFSET, XSCUWDT_CONTROL_WD_ENABLE_MASK, XScuWdt_ReadReg, and XScuWdt_WriteReg.

Referenced by ScuWdtIntrExample(), and ScuWdtPolledExample().

void XScuWdt_Stop

(

XScuWdt *

InstancePtr

)

Stop the watchdog timer.

Parameters

InstancePtr

is a pointer to the XScuWdt instance.

Returns

None.

Note

None.

References XScuWdt_Config::BaseAddr, XScuWdt::Config, XScuWdt::IsReady, XScuWdt::IsStarted, XSCUWDT_CONTROL_OFFSET, XSCUWDT_CONTROL_WD_ENABLE_MASK, XScuWdt_ReadReg, and XScuWdt_WriteReg.

Referenced by ScuWdtIntrExample(), and ScuWdtPolledExample().

Variable Documentation

XScuWdt_Config XScuWdt_ConfigTable[XPAR_XSCUWDT_NUM_INSTANCES]

Initial value:

= {
        {
                (u16)XPAR_SCUWDT_0_DEVICE_ID,
                (u32)XPAR_SCUWDT_0_BASEADDR
        }
}

This table contains configuration information for each watchdog timer device in the system.

Referenced by XScuWdt_LookupConfig().

XScuWdt_Config XScuWdt_ConfigTable[]

This table contains configuration information for each watchdog timer device in the system.

Referenced by XScuWdt_LookupConfig().