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 e627c8f54211..a39bb3d402a2 100644 --- a/Documentation/fb/cyblafb/usage +++ b/Documentation/fb/cyblafb/usage | |||
@@ -40,6 +40,16 @@ Selecting Modes | |||
40 | None of the modes possible to select as startup modes are affected by | 40 | None of the modes possible to select as startup modes are affected by |
41 | the problems described at the end of the next subsection. | 41 | the problems described at the end of the next subsection. |
42 | 42 | ||
43 | For all startup modes cyblafb chooses a virtual x resolution of 2048, | ||
44 | the only exception is mode 1280x1024 in combination with 32 bpp. This | ||
45 | allows ywrap scrolling for all those modes if rotation is 0 or 2, and | ||
46 | also fast scrolling if rotation is 1 or 3. The default virtual y reso- | ||
47 | lution is 4096 for bpp == 8, 2048 for bpp==16 and 1024 for bpp == 32, | ||
48 | again with the only exception of 1280x1024 at 32 bpp. | ||
49 | |||
50 | Please do set your video memory size to 8 Mb in the Bios setup. Other | ||
51 | values will work, but performace is decreased for a lot of modes. | ||
52 | |||
43 | Mode changes using fbset | 53 | Mode changes using fbset |
44 | ======================== | 54 | ======================== |
45 | 55 | ||
@@ -54,20 +64,26 @@ Selecting Modes | |||
54 | - if a flat panel is found, cyblafb does not allow you | 64 | - if a flat panel is found, cyblafb does not allow you |
55 | to program a resolution higher than the physical | 65 | to program a resolution higher than the physical |
56 | resolution of the flat panel monitor | 66 | resolution of the flat panel monitor |
57 | - cyblafb does not allow xres to differ from xres_virtual | ||
58 | - cyblafb does not allow vclk to exceed 230 MHz. As 32 bpp | 67 | - cyblafb does not allow vclk to exceed 230 MHz. As 32 bpp |
59 | and (currently) 24 bit modes use a doubled vclk internally, | 68 | and (currently) 24 bit modes use a doubled vclk internally, |
60 | the dotclock limit as seen by fbset is 115 MHz for those | 69 | the dotclock limit as seen by fbset is 115 MHz for those |
61 | modes and 230 MHz for 8 and 16 bpp modes. | 70 | modes and 230 MHz for 8 and 16 bpp modes. |
71 | - cyblafb will allow you to select very high resolutions as | ||
72 | long as the hardware can be programmed to these modes. The | ||
73 | documented limit 1600x1200 is not enforced, but don't expect | ||
74 | perfect signal quality. | ||
62 | 75 | ||
63 | Any request that violates the rules given above will be ignored and | 76 | Any request that violates the rules given above will be either changed |
64 | fbset will return an error. | 77 | to something the hardware supports or an error value will be returned. |
65 | 78 | ||
66 | If you program a virtual y resolution higher than the hardware limit, | 79 | If you program a virtual y resolution higher than the hardware limit, |
67 | cyblafb will silently decrease that value to the highest possible | 80 | cyblafb will silently decrease that value to the highest possible |
68 | value. | 81 | value. The same is true for a virtual x resolution that is not |
82 | supported by the hardware. Cyblafb tries to adapt vyres first because | ||
83 | vxres decides if ywrap scrolling is possible or not. | ||
69 | 84 | ||
70 | Attempts to disable acceleration are ignored. | 85 | Attempts to disable acceleration are ignored, I believe that this is |
86 | safe. | ||
71 | 87 | ||
72 | Some video modes that should work do not work as expected. If you use | 88 | Some video modes that should work do not work as expected. If you use |
73 | the standard fb.modes, fbset 640x480-60 will program that mode, but | 89 | the standard fb.modes, fbset 640x480-60 will program that mode, but |
@@ -129,10 +145,6 @@ mode 640x480 or 800x600 or 1024x768 or 1280x1024 | |||
129 | verbosity 0 is the default, increase to at least 2 for every | 145 | verbosity 0 is the default, increase to at least 2 for every |
130 | bug report! | 146 | bug report! |
131 | 147 | ||
132 | vesafb allows cyblafb to be loaded after vesafb has been | ||
133 | loaded. See sections "Module unloading ...". | ||
134 | |||
135 | |||
136 | Development hints | 148 | Development hints |
137 | ================= | 149 | ================= |
138 | 150 | ||
@@ -195,7 +207,7 @@ a graphics mode. | |||
195 | After booting, load cyblafb without any mode and bpp parameter and assign | 207 | After booting, load cyblafb without any mode and bpp parameter and assign |
196 | cyblafb to individual ttys using con2fb, e.g.: | 208 | cyblafb to individual ttys using con2fb, e.g.: |
197 | 209 | ||
198 | modprobe cyblafb vesafb=1 | 210 | modprobe cyblafb |
199 | con2fb /dev/fb1 /dev/tty1 | 211 | con2fb /dev/fb1 /dev/tty1 |
200 | 212 | ||
201 | Unloading cyblafb works without problems after you assign vesafb to all | 213 | Unloading cyblafb works without problems after you assign vesafb to all |
@@ -203,4 +215,3 @@ ttys again, e.g.: | |||
203 | 215 | ||
204 | con2fb /dev/fb0 /dev/tty1 | 216 | con2fb /dev/fb0 /dev/tty1 |
205 | rmmod cyblafb | 217 | rmmod cyblafb |
206 | |||