The output of the DisplayPort 1.4 RX Subsystem is always a quad pixel interface (4PPC). By considering the
USER_PIXEL_WIDTH value at the offset address of
now on referred to as USER_PIXEL_WIDTH), 1, 2, or 4PPC from the DisplayPort RX IP is
translated (inside DisplayPort Video to AXI4-Stream Bridge) always into 4PPC output from the
subsystem. With the output of the subsystem as always 4PPC, the need for an external
re-mapper is eliminated, and therefore a significant improvement in resource numbers is
0x010in Table 1 .
By default, this USER_PIXEL_WIDTH mode is equal to the lane count during subsystem generation. You can override this dynamically. For example, if the driver selects a value of 2 for USER_PIXEL_WIDTH as default, you can change this to 1.
As the input data interface of the subsystem is always 4PPC, valid pixels are available in pixel 0, pixel 1, pixel 2, and pixel 3 position.
The data width of the AXI4-Stream interface depends on different parameters of the core.
Pixel_Width = MAX_BPC ×
Interface Width = Pixel Width × 4 (because
the subsystem's intput data interface is always 4.)
For example, if the system is generated with MAX_BPC equal to 16, the data width of the AXI4-Stream interface is 16 × 4 × 3 which equals 192.