DCN Blocks¶

In this section, you will find some extra details about some of the DCN blocks and the code documentation when it is automatically generated.

DCHUBBUB¶

There is only one common DCHUBBUB. It contains the common request and return blocks for the Data Fabric Interface that are not clock/power gated.

HUBP¶

Display Controller Hub (DCHUB) is the gateway between the Scalable Data Port (SDP) and DCN. This component has multiple features, such as memory arbitration, rotation, and cursor manipulation.

There is one HUBP allocated per pipe, which fetches data and converts different pixel formats (i.e. ARGB8888, NV12, etc) into linear, interleaved and fixed-depth streams of pixel data.

DPP¶

The DPP (Display Pipe and Plane) block is the unified display data processing engine in DCN for processing graphic or video data on per DPP rectangle base. This rectangle can be a part of SLS (Single Large Surface), or a layer to be blended with other DPP, or a rectangle associated with a display tile.

It provides various functions including: - graphic color keyer - graphic cursor compositing - graphic or video image source to destination scaling - image sharping - video format conversion from 4:2:0 or 4:2:2 to 4:4:4 - Color Space Conversion - Host LUT gamma adjustment - Color Gamut Remap - brightness and contrast adjustment.

DPP pipe consists of Converter and Cursor (CNVC), Scaler (DSCL), Color Management (CM), Output Buffer (OBUF) and Digital Bypass (DPB) module connected in a video/graphics pipeline.

struct cnv_alpha_2bit_lut¶: Set the 8bit alpha values based on the 2 bit alpha

Definition:

struct cnv_alpha_2bit_lut {
    int lut0;
    int lut1;
    int lut2;
    int lut3;
};

Members

lut0: ALPHA_2BIT_LUT. ALPHA_2BIT_LUT0. Default: 0b00000000
lut1: ALPHA_2BIT_LUT. ALPHA_2BIT_LUT1. Default: 0b01010101
lut2: ALPHA_2BIT_LUT. ALPHA_2BIT_LUT2. Default: 0b10101010
lut3: ALPHA_2BIT_LUT. ALPHA_2BIT_LUT3. Default: 0b11111111

MPC¶

Multiple Pipe/Plane Combiner (MPC) is a component in the hardware pipeline that performs blending of multiple planes, using global and per-pixel alpha. It also performs post-blending color correction operations according to the hardware capabilities, such as color transformation matrix and gamma 1D and 3D LUT.

MPC receives output from all DPP pipes and combines them to multiple outputs supporting “M MPC inputs -> N MPC outputs” flexible composition architecture. It features:

Programmable blending structure to allow software controlled blending and cascading;
Programmable window location of each DPP in active region of display;
Combining multiple DPP pipes in one active region when a single DPP pipe cannot process very large surface;
Combining multiple DPP from different SLS with blending;
Stereo formats from single DPP in top-bottom or side-by-side modes;
Stereo formats from 2 DPPs;
Alpha blending of multiple layers from different DPP pipes;
Programmable background color;

struct mpcc¶: MPCC connection and blending configuration for a single MPCC instance.

Definition:

struct mpcc {
    int mpcc_id;
    int dpp_id;
    struct mpcc *mpcc_bot;
    struct mpcc_blnd_cfg blnd_cfg;
    struct mpcc_sm_cfg sm_cfg;
    bool shared_bottom;
};

Members

mpcc_id: MPCC physical instance.
dpp_id: DPP input to this MPCC
mpcc_bot: Pointer to bottom layer MPCC. NULL when not connected.
blnd_cfg: The blending configuration for this MPCC.
sm_cfg: stereo mix setting for this MPCC
shared_bottom: If MPCC output to both OPP and DWB endpoints, true. Otherwise, false.

Description

This struct is used as a node in an MPC tree.

struct mpc_tree¶: MPC tree represents all MPCC connections for a pipe.

Definition:

struct mpc_tree {
    int opp_id;
    struct mpcc *opp_list;
};

Members

opp_id: The OPP instance that owns this MPC tree.
opp_list: the top MPCC layer of the MPC tree that outputs to OPP endpoint

Description

struct mpc_funcs¶: funcs

Definition:

struct mpc_funcs {
    void (*read_mpcc_state)(struct mpc *mpc,int mpcc_inst, struct mpcc_state *s);
    struct mpcc* (*insert_plane)(struct mpc *mpc,struct mpc_tree *tree,struct mpcc_blnd_cfg *blnd_cfg,struct mpcc_sm_cfg *sm_cfg,struct mpcc *insert_above_mpcc,int dpp_id, int mpcc_id);
    void (*remove_mpcc)(struct mpc *mpc,struct mpc_tree *tree, struct mpcc *mpcc);
    void (*mpc_init)(struct mpc *mpc);
    void (*mpc_init_single_inst)(struct mpc *mpc, unsigned int mpcc_id);
    void (*update_blending)(struct mpc *mpc,struct mpcc_blnd_cfg *blnd_cfg, int mpcc_id);
    void (*cursor_lock)(struct mpc *mpc,int opp_id, bool lock);
    struct mpcc* (*insert_plane_to_secondary)(struct mpc *mpc,struct mpc_tree *tree,struct mpcc_blnd_cfg *blnd_cfg,struct mpcc_sm_cfg *sm_cfg,struct mpcc *insert_above_mpcc,int dpp_id, int mpcc_id);
    void (*remove_mpcc_from_secondary)(struct mpc *mpc,struct mpc_tree *tree, struct mpcc *mpcc);
    struct mpcc* (*get_mpcc_for_dpp_from_secondary)(struct mpc_tree *tree, int dpp_id);
    struct mpcc* (*get_mpcc_for_dpp)(struct mpc_tree *tree, int dpp_id);
    void (*wait_for_idle)(struct mpc *mpc, int id);
    void (*assert_mpcc_idle_before_connect)(struct mpc *mpc, int mpcc_id);
    void (*init_mpcc_list_from_hw)(struct mpc *mpc, struct mpc_tree *tree);
    void (*set_denorm)(struct mpc *mpc,int opp_id, enum dc_color_depth output_depth);
    void (*set_denorm_clamp)(struct mpc *mpc,int opp_id, struct mpc_denorm_clamp denorm_clamp);
    void (*set_output_csc)(struct mpc *mpc,int opp_id,const uint16_t *regval, enum mpc_output_csc_mode ocsc_mode);
    void (*set_ocsc_default)(struct mpc *mpc,int opp_id,enum dc_color_space color_space, enum mpc_output_csc_mode ocsc_mode);
    void (*set_output_gamma)(struct mpc *mpc,int mpcc_id, const struct pwl_params *params);
    void (*power_on_mpc_mem_pwr)(struct mpc *mpc,int mpcc_id, bool power_on);
    void (*set_dwb_mux)(struct mpc *mpc,int dwb_id, int mpcc_id);
    void (*disable_dwb_mux)(struct mpc *mpc, int dwb_id);
    bool (*is_dwb_idle)(struct mpc *mpc, int dwb_id);
    void (*set_out_rate_control)(struct mpc *mpc,int opp_id,bool enable,bool rate_2x_mode, struct mpc_dwb_flow_control *flow_control);
    void (*set_gamut_remap)(struct mpc *mpc,int mpcc_id, const struct mpc_grph_gamut_adjustment *adjust);
    bool (*program_1dlut)(struct mpc *mpc,const struct pwl_params *params, uint32_t rmu_idx);
    bool (*program_shaper)(struct mpc *mpc,const struct pwl_params *params, uint32_t rmu_idx);
    uint32_t (*acquire_rmu)(struct mpc *mpc, int mpcc_id, int rmu_idx);
    bool (*program_3dlut)(struct mpc *mpc,const struct tetrahedral_params *params, int rmu_idx);
    int (*release_rmu)(struct mpc *mpc, int mpcc_id);
    unsigned int (*get_mpc_out_mux)(struct mpc *mpc, int opp_id);
    void (*set_bg_color)(struct mpc *mpc,struct tg_color *bg_color, int mpcc_id);
    void (*set_mpc_mem_lp_mode)(struct mpc *mpc);
    void (*set_movable_cm_location)(struct mpc *mpc, enum mpcc_movable_cm_location location, int mpcc_id);
    void (*update_3dlut_fast_load_select)(struct mpc *mpc, int mpcc_id, int hubp_idx);
    void (*get_3dlut_fast_load_status)(struct mpc *mpc, int mpcc_id, uint32_t *done, uint32_t *soft_underflow, uint32_t *hard_underflow);
    void (*populate_lut)(struct mpc *mpc, const enum MCM_LUT_ID id, const union mcm_lut_params params, bool lut_bank_a, int mpcc_id);
    void (*program_lut_read_write_control)(struct mpc *mpc, const enum MCM_LUT_ID id, bool lut_bank_a, int mpcc_id);
    void (*program_lut_mode)(struct mpc *mpc, const enum MCM_LUT_ID id, const enum MCM_LUT_XABLE xable, bool lut_bank_a, int mpcc_id);
    void (*program_3dlut_size)(struct mpc *mpc, bool is_17x17x17, int mpcc_id);
};

Members

read_mpcc_state

Read register content from given MPCC physical instance.

Parameters:

[in/out] mpc - MPC context
[in] mpcc_instance - MPC context instance
[in] mpcc_state - MPC context state

Return:

void

insert_plane

Insert DPP into MPC tree based on specified blending position. Only used for planes that are part of blending chain for OPP output

Parameters:

[in/out] mpc - MPC context.
[in/out] tree - MPC tree structure that plane will be added to.
[in] blnd_cfg - MPCC blending configuration for the new blending layer.
[in] sm_cfg - MPCC stereo mix configuration for the new blending layer.
stereo mix must disable for the very bottom layer of the tree config.
[in] insert_above_mpcc - Insert new plane above this MPCC.
If NULL, insert as bottom plane.
[in] dpp_id - DPP instance for the plane to be added.
[in] mpcc_id - The MPCC physical instance to use for blending.

Return:

struct mpcc* - MPCC that was added.

remove_mpcc

Remove a specified MPCC from the MPC tree.

Parameters:

[in/out] mpc - MPC context.
[in/out] tree - MPC tree structure that plane will be removed from.
[in/out] mpcc - MPCC to be removed from tree.

Return:

void

mpc_init

Reset the MPCC HW status by disconnecting all muxes.

Parameters:

[in/out] mpc - MPC context.

Return:

void

mpc_init_single_inst

Initialize given MPCC physical instance.

Parameters: - [in/out] mpc - MPC context. - [in] mpcc_id - The MPCC physical instance to be initialized.

update_blending

Update the blending configuration for a specified MPCC.

Parameters:

[in/out] mpc - MPC context.
[in] blnd_cfg - MPCC blending configuration.
[in] mpcc_id - The MPCC physical instance.

Return:

void

cursor_lock

Lock cursor updates for the specified OPP. OPP defines the set of MPCC that are locked together for cursor.

Parameters:

[in] mpc - MPC context.
[in] opp_id - The OPP to lock cursor updates on
[in] lock - lock/unlock the OPP

Return:

void

insert_plane_to_secondary

Add DPP into secondary MPC tree based on specified blending position. Only used for planes that are part of blending chain for DWB output

Parameters:

[in/out] mpc - MPC context.
[in/out] tree - MPC tree structure that plane will be added to.
[in] blnd_cfg - MPCC blending configuration for the new blending layer.
[in] sm_cfg - MPCC stereo mix configuration for the new blending layer.
stereo mix must disable for the very bottom layer of the tree config.
[in] insert_above_mpcc - Insert new plane above this MPCC. If
NULL, insert as bottom plane.
[in] dpp_id - DPP instance for the plane to be added.
[in] mpcc_id - The MPCC physical instance to use for blending.

Return:

struct mpcc* - MPCC that was added.

remove_mpcc_from_secondary

Remove a specified DPP from the ‘secondary’ MPC tree.

Parameters:

[in/out] mpc - MPC context.
[in/out] tree - MPC tree structure that plane will be removed from.
[in] mpcc - MPCC to be removed from tree.

Return:

void

get_mpcc_for_dpp_from_secondary

Find, if it exists, a MPCC from a given ‘secondary’ MPC tree that is associated with specified plane.

Parameters: - [in/out] tree - MPC tree structure to search for plane. - [in] dpp_id - DPP to be searched.

Return:

struct mpcc* - pointer to plane or NULL if no plane found.

get_mpcc_for_dpp

Find, if it exists, a MPCC from a given MPC tree that is associated with specified plane.

Parameters: - [in/out] tree - MPC tree structure to search for plane. - [in] dpp_id - DPP to be searched.

Return:

struct mpcc* - pointer to plane or NULL if no plane found.

wait_for_idle

Wait for a MPCC in MPC context to enter idle state.

Parameters: - [in/out] mpc - MPC Context. - [in] id - MPCC to wait for idle state.

Return:

void

assert_mpcc_idle_before_connect

Assert if MPCC in MPC context is in idle state.

Parameters: - [in/out] mpc - MPC context. - [in] id - MPCC to assert idle state.

Return:

void

init_mpcc_list_from_hw

Iterate through the MPCC array from a given MPC context struct and configure each MPCC according to its registers’ values.

Parameters: - [in/out] mpc - MPC context to initialize MPCC array. - [in/out] tree - MPC tree structure containing MPCC contexts to initialize.

Return:

void

set_denorm

Set corresponding OPP DENORM_CONTROL register value to specific denorm_mode based on given color depth.

Parameters: - [in/out] mpc - MPC context. - [in] opp_id - Corresponding OPP to update register. - [in] output_depth - Arbitrary color depth to set denorm_mode.

Return:

void

set_denorm_clamp

Set denorm clamp values on corresponding OPP DENORM CONTROL register.

Parameters: - [in/out] mpc - MPC context. - [in] opp_id - Corresponding OPP to update register. - [in] denorm_clamp - Arbitrary denorm clamp to be set.

Return:

void

set_output_csc

Set the Output Color Space Conversion matrix with given values and mode.

Parameters: - [in/out] mpc - MPC context. - [in] opp_id - Corresponding OPP to update register. - [in] regval - Values to set in CSC matrix. - [in] ocsc_mode - Mode to set CSC.

Return:

void

set_ocsc_default

Set the Output Color Space Conversion matrix to default values according to color space.

Parameters: - [in/out] mpc - MPC context. - [in] opp_id - Corresponding OPP to update register. - [in] color_space - OCSC color space. - [in] ocsc_mode - Mode to set CSC.

Return:

void

set_output_gamma

Set Output Gamma with given curve parameters.

Parameters: - [in/out] mpc - MPC context. - [in] mpcc_id - Corresponding MPC to update registers. - [in] params - Parameters.

Return:

void

power_on_mpc_mem_pwr

Power on/off memory LUT for given MPCC. Powering on enables LUT to be updated. Powering off allows entering low power mode.

Parameters: - [in/out] mpc - MPC context. - [in] mpcc_id - MPCC to power on. - [in] power_on

Return:

void

set_dwb_mux

Set corresponding Display Writeback mux MPC register field to given MPCC id.

Parameters: - [in/out] mpc - MPC context. - [in] dwb_id - DWB to be set. - [in] mpcc_id - MPCC id to be stored in DWB mux register.

Return:

void

disable_dwb_mux

Reset corresponding Display Writeback mux MPC register field.

Parameters: - [in/out] mpc - MPC context. - [in] dwb_id - DWB to be set.

Return:

void

is_dwb_idle

Check DWB status on MPC_DWB0_MUX_STATUS register field. Return if it is null.

Parameters: - [in/out] mpc - MPC context. - [in] dwb_id - DWB to be checked.

Return:

bool - wheter DWB is idle or not

set_out_rate_control

Set display output rate control.

Parameters: - [in/out] mpc - MPC context. - [in] opp_id - OPP to be set. - [in] enable - [in] rate_2x_mode - [in] flow_control

Return:

void

set_gamut_remap

Set post-blending CTM for given MPCC.

Parameters: - [in] mpc - MPC context. - [in] mpcc_id - MPCC to set gamut map. - [in] adjust

Return:

void

program_1dlut

Set 1 dimensional Lookup Table.

Parameters: - [in/out] mpc - MPC context - [in] params - curve parameters for the LUT configuration - [in] rmu_idx

bool - wheter LUT was set (set with given parameters) or not (params is NULL and LUT is disabled).

program_shaper

Set shaper.

Parameters: - [in/out] mpc - MPC context - [in] params - curve parameters to be set - [in] rmu_idx

Return:

bool - wheter shaper was set (set with given parameters) or not (params is NULL and LUT is disabled).

acquire_rmu

Set given MPCC to be multiplexed to given RMU unit.

Parameters: - [in/out] mpc - MPC context - [in] mpcc_id - MPCC - [in] rmu_idx - Given RMU unit to set MPCC to be multiplexed to.

Return:

unit32_t - rmu_idx if operation was successful, -1 else.

program_3dlut

Set 3 dimensional Lookup Table.

Parameters: - [in/out] mpc - MPC context - [in] params - tetrahedral parameters for the LUT configuration - [in] rmu_idx

bool - wheter LUT was set (set with given parameters) or not (params is NULL and LUT is disabled).

release_rmu

For a given MPCC, release the RMU unit it muliplexes to.

Parameters: - [in/out] mpc - MPC context - [in] mpcc_id - MPCC

Return:

int - a valid rmu_idx representing released RMU unit or -1 if there was no RMU unit to release.

get_mpc_out_mux

Return MPC out mux.

Parameters: - [in] mpc - MPC context. - [in] opp_id - OPP

Return:

unsigned int - Out Mux

set_bg_color

Find corresponding bottommost MPCC and set its bg color.

Parameters: - [in/out] mpc - MPC context. - [in] bg_color - background color to be set. - [in] mpcc_id

Return:

void

set_mpc_mem_lp_mode

Set mpc_mem_lp_mode.

Parameters: - [in/out] mpc - MPC context.

Return:

void

set_movable_cm_location

Set Movable CM Location.

Parameters: - [in/out] mpc - MPC context. - [in] location - [in] mpcc_id

Return:

void

update_3dlut_fast_load_select

Update 3D LUT fast load select.

Parameters: - [in/out] mpc - MPC context. - [in] mpcc_id - [in] hubp_idx

Return:

void

get_3dlut_fast_load_status

Get 3D LUT fast load status and reference them with done, soft_underflow and hard_underflow pointers.

Parameters: - [in/out] mpc - MPC context. - [in] mpcc_id - [in/out] done - [in/out] soft_underflow - [in/out] hard_underflow

Return:

void

populate_lut

Populate LUT with given tetrahedral parameters.

Parameters: - [in/out] mpc - MPC context. - [in] id - [in] params - [in] lut_bank_a - [in] mpcc_id

Return:

void

program_lut_read_write_control

Program LUT RW control.

Parameters: - [in/out] mpc - MPC context. - [in] id - [in] lut_bank_a - [in] mpcc_id

Return:

void

program_lut_mode

Program LUT mode.

Parameters: - [in/out] mpc - MPC context. - [in] id - [in] xable - [in] lut_bank_a - [in] mpcc_id

Return:

void

program_3dlut_size

Program 3D LUT size.

Parameters: - [in/out] mpc - MPC context. - [in] is_17x17x17 - is 3dlut 17x17x17 - [in] mpcc_id

Return:

void

OPP¶

The Output Plane Processor (OPP) block groups have functions that format pixel streams such that they are suitable for display at the display device. The key functions contained in the OPP are:

Adaptive Backlight Modulation (ABM)
Formatter (FMT) which provide pixel-by-pixel operations for format the incoming pixel stream.
Output Buffer that provide pixel replication, and overlapping.
Interface between MPC and OPTC.
Clock and reset generation.
CRC generation.

struct pwl_float_data¶: Fixed point RGB color

Definition:

struct pwl_float_data {
    struct fixed31_32 r;
    struct fixed31_32 g;
    struct fixed31_32 b;
};

Members

r: Component Red.
g: Component Green.
b: Component Blue.

DIO¶

Display Input Output (DIO), is the display input and output unit in DCN. It includes output encoders to support different display output, like DisplayPort, HDMI, DVI interface, and others. It also includes the control and status channels for these interfaces.

bool can_use_dio_link_hwss(const struct dc_link *link, const struct link_resource *link_res)¶: Check if the link_hwss is accessible

Parameters

const struct dc_link *link: Reference a link struct containing one or more sinks and the connective status.
const struct link_resource *link_res: Mappable hardware resource used to enable a link.

Return

Return true if the link encoder is accessible from link.

const struct link_hwss *get_dio_link_hwss(void)¶: Return link_hwss reference

Parameters

void: no arguments

Description

This function behaves like a get function to return the link_hwss populated in the link_hwss_dio.c file.

Return

Return the reference to the filled struct of link_hwss.

The Linux Kernel

Contents

This Page

DCN Blocks¶

DCHUBBUB¶

HUBP¶

DPP¶

MPC¶

OPP¶

DIO¶