NVM_SURF_ATTR_LAYOUT Attribute

Specifies the storage layout of the pixels. The value may be:

• NVM_SURF_ATTR_LAYOUT_PL

  Indicates pitch-linear layout, using pitch-linear mapping, in which pixels are assigned incrementing addresses across each successive row of the image. A surface's pixel addresses are calculated by:

  address = offset + pitch * py + pixel * px

  Where:

  • address is the byte address of a pixel in the surface
  • offset is the address of the surface
  • pitch is the number of bytes occupied by the pixels in a line
  • p_y is the pixel's Y coordinate
  • pixel is the number of bytes occupied by a pixel
  • p_x is the pixel's X coordinate

  Although pitch addressing is standard across most hardware and software platforms, it limits performance because it has poor memory locality, due to the fact that each line in a surface image generally maps to a different DRAM page.

• NVM_SURF_ATTR_LAYOUT_BL

  Indicates block-linear layout. This layout is similar to pitch-linear layout, but maps blocks of pixels using pitch-linear addressing, rather than individual pixels. This layout provides spatial locality for addressing and improves memory access performance. Pixel data layout within a block is an internal detail of the NVIDIA SoC design, and varies across NVIDIA SoC architectures.