• Joonyoung Shim's avatar
    drm/exynos: add G2D driver · d7f1642c
    Joonyoung Shim authored
    Changelog v3:
    - use __u64 instead of pointer in ioctl struct.
    
    The G2D is a 2D graphic accelerator that supports Bit Block Transfer.
    This G2D driver is exynos drm specific and supports only G2D(version
    4.1) of later Exynos series from Exynos4X12 because supporting DMA.
    
    The G2D is performed by two tasks simply.
    1. Configures the rendering parameters, such as foreground color and
       coordinates data by setting the drawing context registers.
    2. Start the rendering process by setting thre relevant command
       registers accordingly.
    
    The G2D version 4.1 supports DMA mode as host interface. User can make
    command list to reduce HOST(ARM) loads. The contents of The command list
    is setted to relevant registers of G2D by DMA.
    
    The command list is composed Header and command sets and Tail.
    - Header: The number of command set(4Bytes)
    - Command set: Register offset(4Bytes) + Register data(4Bytes)
    - Tail: Pointer of base address of the other command list(4Bytes)
    
    By Tail field, the G2D can process many command lists without halt at
    one go.
    
    The G2D has following the rendering pipeline.
    --> Primitive Drawing --> Rotation --> Clipping --> Bilinear Sampling
    --> Color Key --> ROP --> Mask Operation --> Alpha Blending -->
    Dithering --> FrameBuffer
    
    And supports various operations from the rendering pipeline.
    - copy
    - fast solid color fill
    - window clipping
    - rotation
    - flip
    - 4 operand raster operation(ROP4)
    - masking operation
    - alpha blending
    - color key
    - dithering
    - etc
    
    User should make the command list to data and registers needed by
    operation to use. The Exynos G2D driver only manages the command lists
    received from user. Some registers needs memory base address(physical
    address) of image. User doesn't know its physical address, so fills the
    gem handle of that memory than address to command sets, then G2D driver
    converts it to memory base address.
    
    We adds three ioctls and one event for Exynos G2D.
    
    - ioctls
    DRM_EXYNOS_G2D_GET_VER: get the G2D hardware version
    DRM_EXYNOS_G2D_SET_CMDLIST: set the command list from user to driver
    DRM_EXYNOS_G2D_EXEC: execute the command lists setted to driver
    
    - event
    DRM_EXYNOS_G2D_EVENT: event to give notification completion of the
    		      command list to user
    Signed-off-by: default avatarJoonyoung Shim <jy0922.shim@samsung.com>
    Signed-off-by: default avatarInki Dae <inki.dae@samsung.com>
    Signed-off-by: default avatarKyungmin Park <kyungmin.park@samsung.com>
    d7f1642c
exynos_drm_drv.h 10.7 KB