Video and Vision Processing Suite Intel® FPGA IP User Guide

ID 683329
Date 2/15/2022
Public

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Document Table of Contents

21.5. Video Frame Buffer IP Software API

The IP has a software driver for software control of the IP at run time. The IP does not fit any of the generic device models provided by the Nios II HAL. It exposes a set of dedicated accessors to the control and status registers. The driver structure inherits the base driver structure so all common methods described in Video and Vision Processing IPs Software API are applicable.

Register definition header file: intel_vvp_vfb_regs.h

Include file: intel_vvp_vfb.h

Table 356.  Video Frame Buffer IP API Reference
Name Description
intel_vvp_vfb_init Initialize the Frame Buffer instance.
Intel_vvp_core_* .Accessors defined in Video and Vision Processing IPs Software Programming Model . Writable when Lite is on. Readable when Lite is off and Debug features is on.
intel_vvp_v fb_get_lite_mode Returns if Lite mode is on
intel_vvp_v fb_get_debug_enabled Returns if Debug features is on
intel_vvp_vfb_get_max_width Returns the maximum line width.
intel_vvp_vfb_get_max_height Returns the maximum frame height.
intel_vvp_vfb_is_frame_drop_enabled Returns if the IP can drop frame for frame rate conversion.
intel_vvp_vfb_is_frame_repeat_enabled Returns if the IP can repeat frame for frame rate conversion.
intel_vvp_are_invalid_frames_dropped Returns if the Frame Buffer will drop invalid frames.
intel_vvp_vfb_get_mem_base_address Returns the memory base address.
intel_vvp_vfb_get_buffer_stride Returns the number of bytes allocated to each individual frame buffer in memory.
intel_vvp_vfb_get_line_stride Returns the number of bytes allocated to each individual video line in memory.
intel_vvp_vfb_get_bits_per_sample Returns the number of bits per color sample set at compile-time.
intel_vvp_vfb_get_num_color_planes Returns the number of color planes set at compile-time.
intel_vvp_vfb_get_pixels_in_parallel Returns the number of pixels transmitted in parallel on the video path (per clock cycle).
intel_vvp_vfb_get_mem_word_packing Returns how tightly video data is packed in memory words.
intel_vvp_vfb_is_input_running Returns if the IP is currently processing input data.
intel_vvp_vfb_get_input_status Reads the input status register.
intel_vvp_vfb_is_output_running Returns if the IP is currently producing output data.
intel_vvp_vfb_get_output_status Reads the output status register.
intel_vvp_vfb_get_num_input_fields Returns the number of fields received on the input.
intel_vvp_vfb_get_num_dropped_fields Returns the number of input fields dropped.
intel_vvp_vfb_get_num_invalid_fields Returns the number of invalid input fields.
intel_vvp_vfb_get_num_output_fields Returns the number of fields sent.
intel_vvp_vfb_get_num_repeated_fields Returns the number of repeated fields sent.
intel_vvp_vfb_output_enable Enables the frame buffer output.
intel_vvp_vfb_is_output_enabled Returns if the output is on or off.

enum eIntelVvpVfbPacking

Members

kIntelVvpVfbPerfectPacking – Compact sample packing, memory words are fully utilized

kIntelVvpVfbColorPacking – Memory words are packed with an integer number of color samples

kIntelVvpVfbPixelPacking– Memory words are packed with an integer number of pixels

kIntelVvpInvalidClipping – Invalid packing (used to indicate errors)

Description

Enumeration for the supported packing methods

intel_vvp_vfb_init

Prototype
int intel_vvp_vfb_init(intel_vvp_vfb_instance *instance, intel_vvp_core_base base);
Description

Initializes a Frame Buffer instance. The initialization stops early if the vendor ID or product ID read at the base address are not a match or if the register map version is not supported. Otherwise, the function proceeds to read and store the IP compile-time parameterization. The instance is not fully initialized and you should not use further by the application if returning a non-zero error code.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

base – base address of the register map

Returns

kIntelVvpCoreOk (0) in case of success, a negative error code in case of error

kIntelVvpCoreVidErr if the vendor id of the core is not the Intel FPGA vendor ID (0x6AF7).

kIntelVvpCorePidErr if the product_id does not match with the Frame Buffer product ID

kIntelVvpCoreInstanceErr if the instance is a null pointer

kIntelVvpVfbRegMapVersionErr if the register map is not supported

intel_vvp_vfb_get_lite_mode

Prototype
 bool intel_vvp_vfb_get_lite_mode(intel_vvp_vfb_instance *instance);
Description

Returns the value of the LITE_MODE register. The instance must be a valid intel_vvp_vfb_instance fully initialized

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

true if the IP is parameterized in lite mode

intel_vvp_vfb_get_debug_enabled

Prototype
 bool intel_vvp_vfb_get_debug_enabled(intel_vvp_vfb_instance *instance);
Description

Returns the value of the DEBUG_ENABLED register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

true if the IP is parameterized with debug features enabled

intel_vvp_vfb_get_max_width

Prototype
 uint32_t intel_vvp_vfb_get_max_width(intel_vvp_vfb_instance *instance);
Description

Returns the value of the MAX_WIDTH register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

the maximum supported line width

intel_vvp_vfb_get_max_height

Prototype
 uint32_t intel_vvp_vfb_get_max_height(intel_vvp_vfb_instance *instance);
Description

Returns the value of the MAX_HEIGHT register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

the maximum supported frame height

intel_vvp_vfb_is_frame_drop_enabled

Prototype
 bool intel_vvp_vfb_is_frame_drop_enabled(intel_vvp_vfb_instance *instance);
Description

Returns the value of the DROP_ENABLED register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

If frames are dropped for the purpose of frame rate conversion

intel_vvp_vfb_is_frame_repeat_enabled

Prototype
 bool intel_vvp_vfb_is_frame_repeat_enabled(intel_vvp_vfb_instance *instance);
Description

Returns the value of the REPEAT_ENABLED register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

If frames are repeated for the purpose of frame rate conversion

intel_vvp_are_invalid_frames_dropped

Prototype
 bool intel_vvp_are_invalid_frames_dropped(intel_vvp_vfb_instance *instance);
Description

Returns the value of the INVALID_FRAMES_DROPPED register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

If detected invalid frames are dropped

intel_vvp_vfb_get_mem_base_address

Prototype
 uint32_t intel_vvp_vfb_get_mem_base_address(intel_vvp_vfb_instance *instance);
Description

Reads and returns the value of the MEM_BASE_ADDR register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

the base address of the frame buffers in memory

intel_vvp_vfb_get_buffer_stride

Prototype
uint32_t intel_vvp_vfb_get_buffer_stride(intel_vvp_vfb_instance *instance);
Description

Reads and returns the value of the MEM_BUFFER_STRIDE register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

the stride, in bytes, between two contiguous frame buffers in memory

intel_vvp_vfb_get_line_stride

Prototype
uint32_t intel_vvp_vfb_get_line_stride(intel_vvp_vfb_instance *instance);
Description

Reads and returns the value of the MEM_LINE_STRIDE register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

the stride, in bytes, between two contiguous video lines in a frame buffer in memory

intel_vvp_vfb_get_bits_per_sample

Prototype
 uint8_t intel_vvp_vfb_get_bits_per_sample(intel_vvp_vfb_instance *instance);
Description

Reads and returns the value of the BPS register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

the compile-time bits per color sample value

intel_vvp_vfb_get_num_color_planes

Prototype
uint8_t intel_vvp_vfb_get_num_color_planes(intel_vvp_vfb_instance *instance);
Description

Reads and returns the value of the NUMBER_OF_COLOR_PLANES register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

the number of color planes per pixel

intel_vvp_vfb_get_pixels_in_parallel

Prototype
 uint8_t intel_vvp_vfb_get_pixels_in_parallel(intel_vvp_vfb_instance *instance);
Description

Reads and returns the value of the PIXELS_IN_PARALLEL register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

the number of pixels transmitted in parallel per clock cycle

intel_vvp_vfb_get_mem_word_packing

Prototype
eIntelVvpVfbPacking intel_vvp_vfb_get_mem_ word_packing (intel_vvp_vfb_instance *instance);
Description

Reads and returns the value of the PACKING register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns the method used to pack pixels into memory words

intel_vvp_vfb_is_input_running

Prototype
bool intel_vvp_vfb_is_input_running(intel_vvp_vfb_instance* instance);
Description

Reads and returns the running bit of the INPUT_STATUS register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

True is the IP is currently receiving/storing an input field, false when between two input fields

intel_vvp_vfb_get_input_status

Prototype
uint32_t intel_vvp_vfb_get_input_status(intel_vvp_vfb_instance* instance);
Description

Reads the INPUT_STATUS register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

The content of the INPUT_STATUS register

intel_vvp_vfb_is_output_running

Prototype
 bool intel_vvp_vfb_is_output_running(intel_vvp_vfb_instance* instance);
Description

Reads and returns the running bit of the OUTPUT_STATUS register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

True is the IP is currently reading/producing an output field, false when between two output fields

intel_vvp_vfb_get_output_status

Prototype
 uint32_t intel_vvp_vfb_get_output_status(intel_vvp_vfb_instance* instance);
Description

Reads the OUTPUT_STATUS register. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

The content of the OUTPUT_STATUS register

intel_vvp_vfb_get_num_input_fields

Prototype
uint32_t intel_vvp_vfb_get_num_input_fields (intel_vvp_vfb_instance* instance);
Description

Reads the NUM_INPUT_FIELDS register. This is the number of fields received and processed on the Frame Buffer input side. The counter is updated at the end of a field. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

The content of the NUM_INPUT_FIELDS register

intel_vvp_vfb_get_num_dropped_fields

Prototype
uint32_t intel_vvp_vfb_get_num_dropped_fields (intel_vvp_vfb_instance* instance);
Description

Reads the NUM_DROPPED_FIELDS register. This is the number of fields received and dropped on the Frame Buffer input side. The counter is updated when the decision to drop the field is made at the start of the next input field. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

The content of the NUM_ DROPPED _FIELDS register

intel_vvp_vfb_get_num_invalid_fields

Prototype

uint32_t intel_vvp_vfb_get_num_invalid_fields(intel_vvp_vfb_instance* instance);

Description

Reads the NUM_INVALID_FIELDS register. This is the number of fields detected as invalid on the Frame Buffer input side. The counter is updated at the end of a field. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

The content of the NUM_INVALID_FIELDS register

intel_vvp_vfb_get_num_output_fields

Prototype
 uint32_t intel_vvp_vfb_get_num_output_fields (intel_vvp_vfb_instance* instance);
Description

Reads the NUM_OUTPUT_FIELDS register. This is the total number of fields sent on the Frame Buffer output side. The counter is updated at the end of each output field, including repeats. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

The content of the NUM_OUTPUT_FIELDS register

intel_vvp_vfb_get_num_repeated_fields

Prototype
uint32_t intel_vvp_vfb_get_num_repeated_fields (intel_vvp_vfb_instance* instance);
Description

Reads the NUM_REPEATED_FIELDS register. This is the number of repeats on the Frame Buffer output side. If a single field is sent five times, the counter for the number of output fields increases by five whereas the counter for the number of repeated fields increases by four. The counter is increment at the end of each repeated fields. The instance must be a valid intel_vvp_vfb_instance fully initialized.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

Returns

The content of the NUM_REPEATED_FIELDS register

intel_vvp_vfb_output_enable

Prototype
 int intel_vvp_vfb_output_enable(intel_vvp_vfb_instance* instance, bool enabled);
Description

Starts/stops the output side of the Frame Buffer. The instance must be a valid intel_vvp_vfb_instance fully initialized. Note that, if dropping fields is not enabled, stopping the output will cause back-pressure at the input.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

enabled – true to start the output, false to stop it

Returns

kIntelVvpCoreOk or a negative error code in case of error

intel_vvp_vfb_is_output_enabled

Prototype

bool intel_vvp_vfb_is_output_enabled(intel_vvp_vfb_instance* instance);

Description

Starts and stops the output side of the Frame Buffer. The instance must be a valid intel_vvp_vfb_instance fully initialized and configured in debug mode.

Arguments

instance – pointer to the intel_vvp_vfb_instance software driver instance structure

enabled – true to start the output, false to stop it

Returns

kIntelVvpCoreOk (0) or a negative error code in case of error