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.