Documentation/fb/modedb.rst

2 modedb default video mode support
6 Currently all frame buffer device drivers have their own video mode databases,
9   - one routine to probe for video modes, which can be used by all frame buffer
11   - one generic video mode database with a fair amount of standard videomodes
13   - the possibility to supply your own mode database for graphics hardware that
14     needs non-standard modes, like amifb and Mac frame buffer drivers (which
17 When a frame buffer device receives a video= option it doesn't know, it should
18 consider that to be a video mode option. If no frame buffer device is specified
19 in a video= option, fbmem considers that to be a global video mode option.
21 Valid mode specifiers (mode_option argument)::
23     <xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m][eDd]
24     <name>[-<bpp>][@<refresh>]
31   - NSTC: 480i output, with the CCIR System-M TV mode and NTSC color encoding
32   - NTSC-J: 480i output, with the CCIR System-M TV mode, the NTSC color
34   - PAL: 576i output, with the CCIR System-B TV mode and PAL color encoding
35   - PAL-M: 480i output, with the CCIR System-M TV mode and PAL color encoding
39 VESA(TM) Coordinated Video Timings instead of looking up the mode from a table.
41 If 'i' is specified, calculate for an interlaced mode.  And if 'm' is
45        Sample usage: 1024x768M@60m - CVT timing with margins
52 signals (e.g. HDMI and DVI-I). For other outputs it behaves like 'e'. If 'd'
56 To force the VGA output to be enabled and drive a specific mode say::
58     video=VGA-1:1280x1024@60me
62     video=LVDS-1:d video=HDMI-1:D
64 Options can also be passed after the mode, using commas as separator.
66        Sample usage: 720x480,rotate=180 - 720x480 mode, rotated by 180 degrees
70   - margin_top, margin_bottom, margin_left, margin_right (integer):
72   - reflect_x (boolean): Perform an axial symmetry on the X axis
73   - reflect_y (boolean): Perform an axial symmetry on the Y axis
74   - rotate (integer): Rotate the initial framebuffer by x
76   - tv_mode: Analog TV mode. One of "NTSC", "NTSC-443", "NTSC-J", "PAL",
77     "PAL-M", "PAL-N", or "SECAM".
78   - panel_orientation, one of "normal", "upside_down", "left_side_up", or
83 -----------------------------------------------------------------------------
85 What is the VESA(TM) Coordinated Video Timings (CVT)?
98 This is the third standard approved by VESA(TM) concerning video timings.  The
99 first was the Discrete Video Timings (DVT) which is  a collection of
100 pre-defined modes approved by VESA(TM).  The second is the Generalized Timing
115 to the global mode database whenever a new mode is released by display
119 determined from its EDID. The version 1.3 of the EDID has extra 128-byte
125     <pix>M<a>[-R]
129 	   a   = aspect ratio (3 - 4:3; 4 - 5:4; 9 - 15:9, 16:9; A - 16:10)
130 	  -R   = reduced blanking
132 	  example:  .48M3-R - 800x600 with reduced blanking
136       - aspect ratio can only be one of the above values
137       - acceptable refresh rates are 50, 60, 70 or 85 Hz only
138       - if reduced blanking, the refresh rate must be at 60Hz
143 -----------------------------------------------------------------------------
145 To find a suitable video mode, you just call::
153 with db/dbsize your non-standard video mode database, or NULL to use the
154 standard video mode database.
156 fb_find_mode() first tries the specified video mode (or any mode that matches,
158 fails, the default mode is tried. If that fails, it walks over all modes.
160 To specify a video mode at bootup, use the following boot options::
162     video=<driver>:<xres>x<yres>[-<bpp>][@refresh]
165 found in drivers/video/fbdev/core/modedb.c.  Check your driver's documentation.
171     amifb	- Amiga chipset frame buffer
172     aty128fb	- ATI Rage128 / Pro frame buffer
173     atyfb	- ATI Mach64 frame buffer
174     pm2fb	- Permedia 2/2V frame buffer
175     pm3fb	- Permedia 3 frame buffer
176     sstfb	- Voodoo 1/2 (SST1) chipset frame buffer
177     tdfxfb	- 3D Fx frame buffer
178     tridentfb	- Trident (Cyber)blade chipset frame buffer
179     vt8623fb	- VIA 8623 frame buffer