AR# 69593

HDMI Receiver (RX) Subsystem - Why are the Horizontal Front Porch (HFP) and Horizontal Back Porch (HBP) swapped in the timing information? Why are some resolutions that were detected in 2016.2 and earlier now being marked as [Custom Mode]?

Description

Why are the Horizontal Front Porch (HFP) and Horizontal Back Porch (HBP) swapped in the timing information?

Why are some resolutions that were detected in 2016.2 and earlier now being marked as [Custom Mode]?

Solution

This is due to the location of the Horizontal Front Porch (HFP) and Horizontal Back Porch (HBP) not matching in the hardware and software driver.

This has been fixed in hardware in the HDMI Reciever Subsystem v3.0 and later, and in Vivado 2017.3 and later.

The user can work around this by changing the following 2 lines in the HDMI RX Software Driver.

In 2017.2 the user would need to change lines 169 and 170 of the xv_hdmirx_hw.h header file in the v_hdmirx_v1_3 driver.

#define XV_HDMIRX_VTD_HFP_OFFSET                        ((XV_HDMIRX_VTD_BASE)+(14*4))   /**< VTD Horizontal Front Porch Register offset */
#define XV_HDMIRX_VTD_HBP_OFFSET                        ((XV_HDMIRX_VTD_BASE)+(13*4))   /**< VTD Horizontal Back Porch Register offset */

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AR# 69593
Date 10/06/2017
Status Active
Type General Article
IP