Introduction

This is DSS Display driver documentation

Sub Modules
	Display IOCTLs

Files
file	dss_disp.h
	DSS Display Driver interface file.

Data Structures
struct	Dss_DispCreateParams
	Structure containing display driver create arguments, used when calling Fvid2_create(). More...

struct	Dss_DispCreateStatus
	Structure containing create status for the display driver. This should be passed as a status argument while creating the driver. More...

struct	Dss_DispPipeCropParams
	Structure containing video pipeline crop configuration. More...

struct	Dss_DispParams
	Structure containing DSS parameters. This structure is used as an argument to IOCTL_DSS_DISP_SET_DSS_PARAMS. More...

struct	Dss_DispPipeMflagParams
	Structure containing Video Pipe Mflag Information. This structure is used as an argument to IOCTL_DSS_DISP_SET_PIPE_MFLAG_PARAMS. More...

struct	Dss_DispCurrentStatus
	Structure containing current status of the display driver. This structure is used as an argument to IOCTL_DSS_DISP_GET_CURRENT_STATUS. More...

struct	Dss_DispPipeSafetyChkParams
	Structure containing Safety Check configuration of Video Port. This structure is used as an argument to IOCTL_DSS_DISP_SET_PIPE_SAFETY_CHK_PARAMS. More...

struct	Dss_DispBufPrgmCbParams
	Structure containing display buffer program callback parameters. This structure is used as an argument to IOCTL_DSS_DISP_REGISTER_BUF_PRGM_CB. More...

struct	Dss_DispPipePrgmCbParams
	Structure containing video pipe program callback parameters. This structure is used as an argument to IOCTL_DSS_DISP_REGISTER_PIPE_PRGM_CB. More...

struct	Dss_DispUnderFlowCbParams
	Structure containing pipe under flow callback parameters. This structure is used as an argument to IOCTL_DSS_DISP_REGISTER_PIPE_UNDERFLOW_CB. More...

struct	Dss_ScRtParams
	Structure containing run time scaler configuration. More...

struct	Dss_FrameRtParams
	Structure containing run time configuration per frame. More...

struct	Dss_DispRtParams
	Structure containing run time configuration of the display driver. This needs to be passed along with frame list to update any supported run time parameters. More...

Functions
static void	Dss_dispCreateParamsInit (Dss_DispCreateParams *createParams)
	Dss_DispCreateParams structure init function. More...

static void	Dss_dispParamsInit (Dss_DispParams *dssParams)
	Dss_DispParams structure init function. More...

static void	Dss_dispPipeMflagParamsInit (Dss_DispPipeMflagParams *pipeMflagParams)
	Dss_DispPipeMflagParams structure init function. More...

static void	Dss_dispPipeSafetyChkParamsInit (Dss_DispPipeSafetyChkParams *pipeSafetyChkParams)
	Dss_DispPipeSafetyChkParams structure init function. More...

static void	Dss_dispBufPrgmCbParamsInit (Dss_DispBufPrgmCbParams *bufPrgmCbParams)
	Dss_DispBufPrgmCbParams structure init function. More...

static void	Dss_dispPipePrgmCbParamsInit (Dss_DispPipePrgmCbParams *pipePrgmCbParams)
	Dss_DispPipePrgmCbParams structure init function. More...

static void	Dss_dispUnderFlowCbParamsInit (Dss_DispUnderFlowCbParams *underFlowCbParams)
	Dss_DispUnderFlowCbParams structure init function. More...

static void	Dss_scRtParamsInit (Dss_ScRtParams *scRtParams)
	Dss_ScRtParams structure init function. More...

static void	Dss_frameRtParamsInit (Dss_FrameRtParams *frameRtParams)
	Dss_FrameRtParams structure init function. More...

static void	Dss_dispRtParamsInit (Dss_DispRtParams *rtParams)
	Dss_DispRtParams structure init function. More...

static void	Dss_dispPipeCropParamsInit (Dss_DispPipeCropParams *cropParams)

Typedefs
typedef Fvid2_Frame (	Dss_DispBufPrgmCbFxn) (Fvid2_Handle handle, Fvid2_Frame *curFrm, uint32_t isFrmRepeat, uint32_t frmRepeatCnt)
	Display driver buffer program callback function prototype. More...

typedef int32_t(*	Dss_DispPipePrgmCbFxn) (Fvid2_Frame progFrm, void appData)
	Display driver video pipe program callback function prototype. More...

typedef void(*	Dss_DispUnderFlowCbFxn) (void *appData)
	Video pipe underflow callback function prototype. More...

typedef void(*	Dss_DispSafetyErrCbFxn) (uint32_t capturedSign, void *appData)
	Video Pipe safety error callback function prototype. More...

Macros
#define	DSS_BUFFER_ALIGNMENT (16U)
	DSS video buffer alignment. All application buffer address and line pitch should be aligned to this byte boundary. More...

Macro Definition Documentation

◆ DSS_BUFFER_ALIGNMENT

#define DSS_BUFFER_ALIGNMENT (16U)

DSS video buffer alignment. All application buffer address and line pitch should be aligned to this byte boundary.

Typedef Documentation

◆ Dss_DispBufPrgmCbFxn

typedef Fvid2_Frame*(* Dss_DispBufPrgmCbFxn) (Fvid2_Handle handle, Fvid2_Frame *curFrm, uint32_t isFrmRepeat, uint32_t frmRepeatCnt)

Display driver buffer program callback function prototype.

This callback is called by the driver when it is about to program the already queued buffer to the hardware. The driver returns the current frame pointer and the application can use this information to check if the buffer to be programmed is too old to display. If it decides so, the application can give a new frame buffer (blank frame) in the return parameter. Then the driver swaps this FVID2 frame pointer in its internal queue and program the new frame provided.

Note: Once the frame is swapped with the driver, the driver will not have any reference to the old frame. The ownership of the old frame is transferred to application and will not be returned in the driver dequeue operation.

User should assume that callbacks happen in ISR context and hence should apply rules relevant to ISR context when implementing callback functions, i.e. blocking APIs should not be called from callback. Users should also assume that interrupts are enabled when in callback context, i.e. other interrupt / callbacks can occur when a callback is under execution. User callback implementation should not be very long, since callback execution may block other drivers from executing. Typically it is recommended to set a semaphore or flag when callback happens and do the more involved callback handling in task context.

Parameters

handle	[OUT] FVID2 handle for which the callback has occurred.
curFrm	[OUT] Current FVID2 frame about to be programmed.
isFrmRepeat	[OUT] Flag to indicate whether the current frame is already programmed in the hardware.
frmRepeatCnt	[OUT] This variable indicates the frame repeat count reflecting the hardware queue depth. In case of DSS, we have actual register and shadow register. Hence this value could be 1 or 2 for most of the cases. 1 means normal operating mode without frame repeat. 2 means both the shadow and current register have the same buffer i.e. the frame is getting repeated. There is a special case when this value is 0. This means the driver is trying to program the register in low latency mode in task context. But the success of the buffer getting accepted depends on when the queue is called with respect to VSYNC. If the Queue call is very near the VSYNC say 10 lines before VSYNC, the buffer programming will not be accepted. And the application should assume that the buffer will gets programmed in the next VSYNC only.

Returns: The application can return the new FVID2 frame to be used for programming the hardware. If the application returns NULL no action is taken and the driver will go ahead and program the current frame to hardware.

◆ Dss_DispPipePrgmCbFxn

typedef int32_t(* Dss_DispPipePrgmCbFxn) (Fvid2_Frame *progFrm, void *appData)

Display driver video pipe program callback function prototype.

This callback is called by the driver after it has programmed the already queued buffer to the hardware. The application can use this callback to simulate a VSYNC. The driver returns the programmed frame pointer to the application.

User should assume that callbacks happen in ISR context and hence should apply rules relevant to ISR context when implementing callback functions, i.e. blocking APIs should not be called from callback. User callback implementation should not be very long, since callback execution may block other drivers from executing. Typically it is recommended to set a semaphore or flag when callback happens and do the more involved callback handling in task context.

Parameters

progFrm	[OUT] Current FVID2 frame that has been programmed.
appData	[OUT] Application's private data.

Returns: Status

◆ Dss_DispUnderFlowCbFxn

typedef void(* Dss_DispUnderFlowCbFxn) (void *appData)

Video pipe underflow callback function prototype.

Parameters

appData [OUT] Application's private data.

Returns: None.

◆ Dss_DispSafetyErrCbFxn

typedef void(* Dss_DispSafetyErrCbFxn) (uint32_t capturedSign, void *appData)

Video Pipe safety error callback function prototype.

Parameters

capturedSign	[OUT] Captured signature
appData	[OUT] Application's private data.

Returns: None.

Returns: None

◆ Dss_dispPipeCropParamsInit()

static void Dss_dispPipeCropParamsInit ( Dss_DispPipeCropParams * cropParams )

inlinestatic

Introduction

Sub Modules

Files

Data Structures

Functions

Typedefs

Macros

Macro Definition Documentation

◆ DSS_BUFFER_ALIGNMENT

Typedef Documentation

◆ Dss_DispBufPrgmCbFxn

◆ Dss_DispPipePrgmCbFxn

◆ Dss_DispUnderFlowCbFxn

◆ Dss_DispSafetyErrCbFxn

Function Documentation

◆ Dss_dispCreateParamsInit()

◆ Dss_dispParamsInit()

◆ Dss_dispPipeMflagParamsInit()

◆ Dss_dispPipeSafetyChkParamsInit()

◆ Dss_dispBufPrgmCbParamsInit()

◆ Dss_dispPipePrgmCbParamsInit()

◆ Dss_dispUnderFlowCbParamsInit()

◆ Dss_scRtParamsInit()

◆ Dss_frameRtParamsInit()

◆ Dss_dispRtParamsInit()

◆ Dss_dispPipeCropParamsInit()