diff options
Diffstat (limited to 'Documentation/fb/cyblafb/usage')
-rw-r--r-- | Documentation/fb/cyblafb/usage | 33 |
1 files changed, 22 insertions, 11 deletions
diff --git a/Documentation/fb/cyblafb/usage b/Documentation/fb/cyblafb/usage index e627c8f5421..a39bb3d402a 100644 --- a/Documentation/fb/cyblafb/usage +++ b/Documentation/fb/cyblafb/usage @@ -40,6 +40,16 @@ Selecting Modes None of the modes possible to select as startup modes are affected by the problems described at the end of the next subsection. + For all startup modes cyblafb chooses a virtual x resolution of 2048, + the only exception is mode 1280x1024 in combination with 32 bpp. This + allows ywrap scrolling for all those modes if rotation is 0 or 2, and + also fast scrolling if rotation is 1 or 3. The default virtual y reso- + lution is 4096 for bpp == 8, 2048 for bpp==16 and 1024 for bpp == 32, + again with the only exception of 1280x1024 at 32 bpp. + + Please do set your video memory size to 8 Mb in the Bios setup. Other + values will work, but performace is decreased for a lot of modes. + Mode changes using fbset ======================== @@ -54,20 +64,26 @@ Selecting Modes - if a flat panel is found, cyblafb does not allow you to program a resolution higher than the physical resolution of the flat panel monitor - - cyblafb does not allow xres to differ from xres_virtual - cyblafb does not allow vclk to exceed 230 MHz. As 32 bpp and (currently) 24 bit modes use a doubled vclk internally, the dotclock limit as seen by fbset is 115 MHz for those modes and 230 MHz for 8 and 16 bpp modes. + - cyblafb will allow you to select very high resolutions as + long as the hardware can be programmed to these modes. The + documented limit 1600x1200 is not enforced, but don't expect + perfect signal quality. - Any request that violates the rules given above will be ignored and - fbset will return an error. + Any request that violates the rules given above will be either changed + to something the hardware supports or an error value will be returned. If you program a virtual y resolution higher than the hardware limit, cyblafb will silently decrease that value to the highest possible - value. + value. The same is true for a virtual x resolution that is not + supported by the hardware. Cyblafb tries to adapt vyres first because + vxres decides if ywrap scrolling is possible or not. - Attempts to disable acceleration are ignored. + Attempts to disable acceleration are ignored, I believe that this is + safe. Some video modes that should work do not work as expected. If you use the standard fb.modes, fbset 640x480-60 will program that mode, but @@ -129,10 +145,6 @@ mode 640x480 or 800x600 or 1024x768 or 1280x1024 verbosity 0 is the default, increase to at least 2 for every bug report! -vesafb allows cyblafb to be loaded after vesafb has been - loaded. See sections "Module unloading ...". - - Development hints ================= @@ -195,7 +207,7 @@ a graphics mode. After booting, load cyblafb without any mode and bpp parameter and assign cyblafb to individual ttys using con2fb, e.g.: - modprobe cyblafb vesafb=1 + modprobe cyblafb con2fb /dev/fb1 /dev/tty1 Unloading cyblafb works without problems after you assign vesafb to all @@ -203,4 +215,3 @@ ttys again, e.g.: con2fb /dev/fb0 /dev/tty1 rmmod cyblafb - |