• Jeykumar Sankaran's avatar
    drm/msm: Add SDM845 DPU support · 25fdd593
    Jeykumar Sankaran authored
    SDM845 SoC includes the Mobile Display Sub System (MDSS) which is a
    top level wrapper consisting of Display Processing Unit (DPU) and
    display peripheral modules such as Display Serial Interface (DSI)
    and DisplayPort (DP).
    
    MDSS functions essentially as a back-end composition engine. It blends
    video and graphic images stored in the frame buffers and scans out the
    composed image to a display sink (over DSI/DP).
    
    The following diagram represents hardware blocks for a simple pipeline
    (two planes are present on a given crtc which is connected to a DSI
    connector):
    
           MDSS
          +---------------------------------+
          | +-----------------------------+ |
          | | DPU                         | |
          | |  +--------+  +--------+     | |
          | |  |  SSPP  |  |  SSPP  |     | |
          | |  +----+---+  +----+---+     | |
          | |       |           |         | |
          | |  +----v-----------v---+     | |
          | |  |  Layer Mixer (LM)  |     | |
          | |  +--------------------+     | |
          | |  +--------------------+     | |
          | |  |    PingPong (PP)   |     | |
          | |  +--------------------+     | |
          | |  +--------------------+     | |
          | |  |  INTERFACE (VIDEO) |     | |
          | |  +---+----------------+     | |
          | +------|----------------------+ |
          |        |                        |
          | +------|---------------------+  |
          | |      | DISPLAY PERIPHERALS |  |
          | |  +---v-+      +-----+      |  |
          | |  | DSI |      |  DP |      |  |
          | |  +-----+      +-----+      |  |
          | +----------------------------+  |
          +---------------------------------+
    
    The number of DPU sub-blocks (i.e. SSPPs, LMs, PP blocks and INTFs)
    depends on SoC capabilities.
    
    Overview of DPU sub-blocks:
    ---------------------------
    * Source Surface Processor (SSPP):
     Refers to any of hardware pipes like ViG, DMA etc. Only ViG pipes are
     capable of performing format conversion, scaling and quality improvement
     for source surfaces.
    
    * Layer Mixer (LM):
     Blend source surfaces together (in requested zorder)
    
    * PingPong (PP):
     This block controls frame done interrupt output, EOL and EOF generation,
     overflow/underflow control.
    
    * Display interface (INTF):
     Timing generator and interface connecting the display peripherals.
    
    DRM components mapping to DPU architecture:
    ------------------------------------------
    PLANEs maps to SSPPs
    CRTC maps to LMs
    Encoder maps to PPs, INTFs
    
    Data flow setup:
    ---------------
    MDSS hardware can support various data flows (e.g.):
      - Dual pipe: Output from two LMs combined to single display.
      - Split display: Output from two LMs connected to two separate
                       interfaces.
    
    The hardware capabilities determine the number of concurrent data paths
    possible. Any control path (i.e. pipeline w/i DPU) can be routed to any
    of the hardware data paths. A given control path can be triggered,
    flushed and controlled independently.
    
    Changes in v3:
    - Move msm_media_info.h from uapi to dpu/ subdir
    - Remove preclose callback dpu (it's handled in core)
    - Fix kbuild warnings with parent_ops
    - Remove unused functions from dpu_core_irq
    - Rename mdss_phys to mdss
    - Rename mdp_phys address space to mdp
    - Drop _phys from vbif and regdma binding names
    Signed-off-by: default avatarAbhinav Kumar <abhinavk@codeaurora.org>
    Signed-off-by: default avatarArchit Taneja <architt@codeaurora.org>
    Signed-off-by: default avatarChandan Uddaraju <chandanu@codeaurora.org>
    Signed-off-by: default avatarJeykumar Sankaran <jsanka@codeaurora.org>
    Signed-off-by: default avatarJordan Crouse <jcrouse@codeaurora.org>
    Signed-off-by: default avatarRajesh Yadav <ryadav@codeaurora.org>
    Signed-off-by: default avatarSravanthi Kollukuduru <skolluku@codeaurora.org>
    Signed-off-by: default avatarSean Paul <seanpaul@chromium.org>
    [robclark minor rebase]
    Signed-off-by: default avatarRob Clark <robdclark@gmail.com>
    25fdd593
dpu_hw_sspp.h 11.1 KB