PINE64
DTS options for HDMI-DVI adapters - Printable Version

+- PINE64 (https://forum.pine64.org)
+-- Forum: PINE A64(+) (https://forum.pine64.org/forumdisplay.php?fid=4)
+--- Forum: Linux on Pine A64(+) (https://forum.pine64.org/forumdisplay.php?fid=6)
+--- Thread: DTS options for HDMI-DVI adapters (/showthread.php?tid=1676)



DTS options for HDMI-DVI adapters - xalius - 07-07-2016

I came across several hints on other Allwinner SoCs like the H3 (which has similar peripherals to the A64, just 32bit cores) where to enable better inter-operability with DVI-HDMI adapters a certain device tree option has to be set:

Code:
... hdmi_hdcp_enable = <0x00000000>; hdmi_cts_compatibility = <0x00000001>; ...


http://linux-sunxi.org/Xunlong_Orange_Pi_One_%26_Lite#HDMI_to_DVI_converters (for example)

We have that option in the extracted device tree used for our Linux Images...

https://github.com/longsleep/build-pine64-image/blob/master/blobs/pine64.dts#L2003

Did anyone with DVI issues try that yet?

Edit: The dts option seems to enable "something" in the display driver, but what exactly is hidden in the binary portion if I see it correctly....

Code:
disp_hdmi.c ... if(gdisp.init_para.hdmi_cts_compatibility == 0) { DE_INF("bsp_disp_hdmi_open: disable dvi mode\n"); bsp_disp_hdmi_dvi_enable(screen_id, 0); } else if(gdisp.init_para.hdmi_cts_compatibility == 1) { DE_INF("bsp_disp_hdmi_open: enable dvi mode\n"); bsp_disp_hdmi_dvi_enable(screen_id, 1); } else { bsp_disp_hdmi_dvi_enable(screen_id, bsp_disp_hdmi_dvi_support(screen_id)); } ...