xref: /rk3399_rockchip-uboot/doc/device-tree-bindings/video/displaymode.txt (revision 9702ec00e95dbc1fd66ef8e9624c649e1ee818e5)
1videomode bindings
2==================
3
4(from http://lists.freedesktop.org/archives/dri-devel/2012-July/024875.html)
5
6Required properties:
7 - xres, yres: Display resolution
8 - left-margin, right-margin, hsync-len: Horizontal Display timing
9   parameters in pixels
10 - upper-margin, lower-margin, vsync-len: Vertical display timing
11   parameters in lines
12 - clock: display clock in Hz
13
14Optional properties:
15 - width-mm, height-mm: Display dimensions in mm
16 - hsync-active-high (bool): Hsync pulse is active high
17 - vsync-active-high (bool): Vsync pulse is active high
18 - interlaced (bool): This is an interlaced mode
19 - doublescan (bool): This is a doublescan mode
20
21There are different ways of describing a display mode. The devicetree
22representation corresponds to the one used by the Linux Framebuffer
23framework described here in Documentation/fb/framebuffer.txt. This
24representation has been chosen because it's the only format which does
25not allow for inconsistent parameters. Unlike the Framebuffer framework
26the devicetree has the clock in Hz instead of ps.
27
28Example:
29
30	display@0 {
31		/* 1920x1080p24 */
32		clock = <52000000>;
33		xres = <1920>;
34		yres = <1080>;
35		left-margin = <25>;
36		right-margin = <25>;
37		hsync-len = <25>;
38		lower-margin = <2>;
39		upper-margin = <2>;
40		vsync-len = <2>;
41		hsync-active-high;
42	};
43