aboutsummaryrefslogtreecommitdiff
path: root/Documentation/fb/viafb.txt
diff options
context:
space:
mode:
authorFathi Boudra <fathi.boudra@linaro.org>2013-04-28 09:33:08 +0300
committerFathi Boudra <fathi.boudra@linaro.org>2013-04-28 09:33:08 +0300
commit3b4bd47f8f4ed3aaf7c81c9b5d2d37ad79fadf4a (patch)
treeb9996006addfd7ae70a39672b76843b49aebc189 /Documentation/fb/viafb.txt
downloadlinux-linaro-highbank-3b4bd47f8f4ed3aaf7c81c9b5d2d37ad79fadf4a.tar.gz
Imported Upstream version 3.9.0HEADupstream/3.9.0upstreammaster
Diffstat (limited to 'Documentation/fb/viafb.txt')
-rw-r--r--Documentation/fb/viafb.txt252
1 files changed, 252 insertions, 0 deletions
diff --git a/Documentation/fb/viafb.txt b/Documentation/fb/viafb.txt
new file mode 100644
index 00000000..444e34b5
--- /dev/null
+++ b/Documentation/fb/viafb.txt
@@ -0,0 +1,252 @@
+
+ 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"
+