|  | 
 |         VIA Integration Graphic Chip Console Framebuffer Driver | 
 |  | 
 | [Platform] | 
 | ----------------------- | 
 |     The console framebuffer driver is for graphics chips of | 
 |     VIA UniChrome Family(CLE266, PM800 / CN400 / CN300, | 
 |                         P4M800CE / P4M800Pro / CN700 / VN800, | 
 |                         CX700 / VX700, K8M890, P4M890, | 
 |                         CN896 / P4M900, VX800, VX855) | 
 |  | 
 | [Driver features] | 
 | ------------------------ | 
 |     Device: CRT, LCD, DVI | 
 |  | 
 |     Support viafb_mode: | 
 |         CRT: | 
 |             640x480(60, 75, 85, 100, 120 Hz), 720x480(60 Hz), | 
 |             720x576(60 Hz), 800x600(60, 75, 85, 100, 120 Hz), | 
 |             848x480(60 Hz), 856x480(60 Hz), 1024x512(60 Hz), | 
 |             1024x768(60, 75, 85, 100 Hz), 1152x864(75 Hz), | 
 |             1280x768(60 Hz), 1280x960(60 Hz), 1280x1024(60, 75, 85 Hz), | 
 |             1440x1050(60 Hz), 1600x1200(60, 75 Hz), 1280x720(60 Hz), | 
 |             1920x1080(60 Hz), 1400x1050(60 Hz), 800x480(60 Hz) | 
 |  | 
 |     color depth: 8 bpp, 16 bpp, 32 bpp supports. | 
 |  | 
 |     Support 2D hardware accelerator. | 
 |  | 
 | [Using the viafb module] | 
 | -- -- -------------------- | 
 |     Start viafb with default settings: | 
 |         #modprobe viafb | 
 |  | 
 |     Start viafb with with user options: | 
 |         #modprobe viafb viafb_mode=800x600 viafb_bpp=16 viafb_refresh=60 | 
 |                   viafb_active_dev=CRT+DVI viafb_dvi_port=DVP1 | 
 |                   viafb_mode1=1024x768 viafb_bpp=16 viafb_refresh1=60 | 
 |                   viafb_SAMM_ON=1 | 
 |  | 
 |     viafb_mode: | 
 |         640x480 (default) | 
 |         720x480 | 
 |         800x600 | 
 |         1024x768 | 
 |         ...... | 
 |  | 
 |     viafb_bpp: | 
 |         8, 16, 32 (default:32) | 
 |  | 
 |     viafb_refresh: | 
 |         60, 75, 85, 100, 120 (default:60) | 
 |  | 
 |     viafb_lcd_dsp_method: | 
 |         0 : expansion (default) | 
 |         1 : centering | 
 |  | 
 |     viafb_lcd_mode: | 
 |         0 : LCD panel with LSB data format input (default) | 
 |         1 : LCD panel with MSB data format input | 
 |  | 
 |     viafb_lcd_panel_id: | 
 |         0 : Resolution: 640x480, Channel: single, Dithering: Enable | 
 |         1 : Resolution: 800x600, Channel: single, Dithering: Enable | 
 |         2 : Resolution: 1024x768, Channel: single, Dithering: Enable (default) | 
 |         3 : Resolution: 1280x768, Channel: single, Dithering: Enable | 
 |         4 : Resolution: 1280x1024, Channel: dual, Dithering: Enable | 
 |         5 : Resolution: 1400x1050, Channel: dual, Dithering: Enable | 
 |         6 : Resolution: 1600x1200, Channel: dual, Dithering: Enable | 
 |  | 
 |         8 : Resolution: 800x480, Channel: single, Dithering: Enable | 
 |         9 : Resolution: 1024x768, Channel: dual, Dithering: Enable | 
 |         10: Resolution: 1024x768, Channel: single, Dithering: Disable | 
 |         11: Resolution: 1024x768, Channel: dual, Dithering: Disable | 
 |         12: Resolution: 1280x768, Channel: single, Dithering: Disable | 
 |         13: Resolution: 1280x1024, Channel: dual, Dithering: Disable | 
 |         14: Resolution: 1400x1050, Channel: dual, Dithering: Disable | 
 |         15: Resolution: 1600x1200, Channel: dual, Dithering: Disable | 
 |         16: Resolution: 1366x768, Channel: single, Dithering: Disable | 
 |         17: Resolution: 1024x600, Channel: single, Dithering: Enable | 
 |         18: Resolution: 1280x768, Channel: dual, Dithering: Enable | 
 |         19: Resolution: 1280x800, Channel: single, Dithering: Enable | 
 |  | 
 |     viafb_accel: | 
 |         0 : No 2D Hardware Acceleration | 
 |         1 : 2D Hardware Acceleration (default) | 
 |  | 
 |     viafb_SAMM_ON: | 
 |         0 : viafb_SAMM_ON disable (default) | 
 |         1 : viafb_SAMM_ON enable | 
 |  | 
 |     viafb_mode1: (secondary display device) | 
 |         640x480 (default) | 
 |         720x480 | 
 |         800x600 | 
 |         1024x768 | 
 |         ... ... | 
 |  | 
 |     viafb_bpp1: (secondary display device) | 
 |         8, 16, 32 (default:32) | 
 |  | 
 |     viafb_refresh1: (secondary display device) | 
 |         60, 75, 85, 100, 120 (default:60) | 
 |  | 
 |     viafb_active_dev: | 
 |         This option is used to specify active devices.(CRT, DVI, CRT+LCD...) | 
 |         DVI stands for DVI or HDMI, E.g., If you want to enable HDMI, | 
 |         set viafb_active_dev=DVI. In SAMM case, the previous of | 
 |         viafb_active_dev is primary device, and the following is | 
 |         secondary device. | 
 |  | 
 |         For example: | 
 |         To enable one device, such as DVI only, we can use: | 
 |             modprobe viafb viafb_active_dev=DVI | 
 |         To enable two devices, such as CRT+DVI: | 
 |             modprobe viafb viafb_active_dev=CRT+DVI; | 
 |  | 
 |         For DuoView case, we can use: | 
 |             modprobe viafb viafb_active_dev=CRT+DVI | 
 |             OR | 
 |             modprobe viafb viafb_active_dev=DVI+CRT... | 
 |  | 
 |         For SAMM case: | 
 |         If CRT is primary and DVI is secondary, we should use: | 
 |             modprobe viafb viafb_active_dev=CRT+DVI viafb_SAMM_ON=1... | 
 |         If DVI is primary and CRT is secondary, we should use: | 
 |             modprobe viafb viafb_active_dev=DVI+CRT viafb_SAMM_ON=1... | 
 |  | 
 |     viafb_display_hardware_layout: | 
 |         This option is used to specify display hardware layout for CX700 chip. | 
 |         1 : LCD only | 
 |         2 : DVI only | 
 |         3 : LCD+DVI (default) | 
 |         4 : LCD1+LCD2 (internal + internal) | 
 |         16: LCD1+ExternalLCD2 (internal + external) | 
 |  | 
 |     viafb_second_size: | 
 |         This option is used to set second device memory size(MB) in SAMM case. | 
 |         The minimal size is 16. | 
 |  | 
 |     viafb_platform_epia_dvi: | 
 |         This option is used to enable DVI on EPIA - M | 
 |         0 : No DVI on EPIA - M (default) | 
 |         1 : DVI on EPIA - M | 
 |  | 
 |     viafb_bus_width: | 
 |         When using 24 - Bit Bus Width Digital Interface, | 
 |         this option should be set. | 
 |         12: 12-Bit LVDS or 12-Bit TMDS (default) | 
 |         24: 24-Bit LVDS or 24-Bit TMDS | 
 |  | 
 |     viafb_device_lcd_dualedge: | 
 |         When using Dual Edge Panel, this option should be set. | 
 |         0 : No Dual Edge Panel (default) | 
 |         1 : Dual Edge Panel | 
 |  | 
 |     viafb_lcd_port: | 
 |         This option is used to specify LCD output port, | 
 |         available values are "DVP0" "DVP1" "DFP_HIGHLOW" "DFP_HIGH" "DFP_LOW". | 
 |         for external LCD + external DVI on CX700(External LCD is on DVP0), | 
 |         we should use: | 
 |             modprobe viafb viafb_lcd_port=DVP0... | 
 |  | 
 | Notes: | 
 |     1. CRT may not display properly for DuoView CRT & DVI display at | 
 |        the "640x480" PAL mode with DVI overscan enabled. | 
 |     2. SAMM stands for single adapter multi monitors. It is different from | 
 |        multi-head since SAMM support multi monitor at driver layers, thus fbcon | 
 |        layer doesn't even know about it; SAMM's second screen doesn't have a | 
 |        device node file, thus a user mode application can't access it directly. | 
 |        When SAMM is enabled, viafb_mode and viafb_mode1, viafb_bpp and | 
 |        viafb_bpp1, viafb_refresh and viafb_refresh1 can be different. | 
 |     3. When console is depending on viafbinfo1, dynamically change resolution | 
 |        and bpp, need to call VIAFB specified ioctl interface VIAFB_SET_DEVICE | 
 |        instead of calling common ioctl function FBIOPUT_VSCREENINFO since | 
 |        viafb doesn't support multi-head well, or it will cause screen crush. | 
 |  | 
 |  | 
 | [Configure viafb with "fbset" tool] | 
 | ----------------------------------- | 
 |     "fbset" is an inbox utility of Linux. | 
 |     1. Inquire current viafb information, type, | 
 |            # fbset -i | 
 |  | 
 |     2. Set various resolutions and viafb_refresh rates, | 
 |            # fbset <resolution-vertical_sync> | 
 |  | 
 |        example, | 
 |            # fbset "1024x768-75" | 
 |        or | 
 |            # fbset -g 1024 768 1024 768 32 | 
 |        Check the file "/etc/fb.modes" to find display modes available. | 
 |  | 
 |     3. Set the color depth, | 
 |            # fbset -depth <value> | 
 |  | 
 |        example, | 
 |            # fbset -depth 16 | 
 |  | 
 |  | 
 | [Configure viafb via /proc] | 
 | --------------------------- | 
 |     The following files exist in /proc/viafb | 
 |  | 
 |     supported_output_devices | 
 |  | 
 |         This read-only file contains a full ',' separated list containing all | 
 |         output devices that could be available on your platform. It is likely | 
 |         that not all of those have a connector on your hardware but it should | 
 |         provide a good starting point to figure out which of those names match | 
 |         a real connector. | 
 |         Example: | 
 |         # cat /proc/viafb/supported_output_devices | 
 |  | 
 |     iga1/output_devices | 
 |     iga2/output_devices | 
 |  | 
 |         These two files are readable and writable. iga1 and iga2 are the two | 
 |         independent units that produce the screen image. Those images can be | 
 |         forwarded to one or more output devices. Reading those files is a way | 
 |         to query which output devices are currently used by an iga. | 
 |         Example: | 
 |         # cat /proc/viafb/iga1/output_devices | 
 |         If there are no output devices printed the output of this iga is lost. | 
 |         This can happen for example if only one (the other) iga is used. | 
 |         Writing to these files allows adjusting the output devices during | 
 |         runtime. One can add new devices, remove existing ones or switch | 
 |         between igas. Essentially you can write a ',' separated list of device | 
 |         names (or a single one) in the same format as the output to those | 
 |         files. You can add a '+' or '-' as a prefix allowing simple addition | 
 |         and removal of devices. So a prefix '+' adds the devices from your list | 
 |         to the already existing ones, '-' removes the listed devices from the | 
 |         existing ones and if no prefix is given it replaces all existing ones | 
 |         with the listed ones. If you remove devices they are expected to turn | 
 |         off. If you add devices that are already part of the other iga they are | 
 |         removed there and added to the new one. | 
 |         Examples: | 
 |         Add CRT as output device to iga1 | 
 |         # echo +CRT > /proc/viafb/iga1/output_devices | 
 |  | 
 |         Remove (turn off) DVP1 and LVDS1 as output devices of iga2 | 
 |         # echo -DVP1,LVDS1 > /proc/viafb/iga2/output_devices | 
 |  | 
 |         Replace all iga1 output devices by CRT | 
 |         # echo CRT > /proc/viafb/iga1/output_devices | 
 |  | 
 |  | 
 | [Bootup with viafb]: | 
 | -------------------- | 
 |     Add the following line to your grub.conf: | 
 |     append = "video=viafb:viafb_mode=1024x768,viafb_bpp=32,viafb_refresh=85" | 
 |  |