As a stick in the ground, I wanted to provide a quick summary of video drivers for the BeagleBoneBlack.
There is the Xorg Kernel Mode Setting Driver : an extremely basic frame buffer driver and the fallback driver if no better Xorg driver is found. It has extremely limited functionality and does not support screen rotation.
There is the Xorg fbdev Driver: a still basic frame buffer driver, but it does support some configuration options including rotate.
There is the tilcdc Driver: Released by Ron Clark at the beginning of 2013. http://lwn.net/Articles/533731/ This driver, if installed, is configured via the Device Tree. For example, see the BB-BONE-LCD7-*.dts files. These files contain the pin connection info and the LCD display configuration information and will be used by the tilcdc driver to configure the display. Note: I do not know what configuration options are supported for userland configuration[ie setting rotation on bootup, or configuring rotation in the Xorg.conf file] This drivers sourcecode is located at drivers/gpu/tilcdc
There is the omap frame buffer driver: Located at drivers/video/omap This driver requires LCD panel configuration information which is available for some LCD panels in the same directory as the driver. Does this work for the BeagleBoneBlack?
There is the omap2 frame buffer driver: Located at drivers/video/omap2/omapfb. This driver requires LCD panel configuration, of which many are already written - see drivers/video/omap2/displays for them. Does this work for the BeagleBoneBlack?
There is the PVRSRVKVM Driver: Uses the built in SGX graphcis processor to accelerate graphics processing and offload processing from the CPU. This driver may not work under Linux Kernel version 3.8. According to the latest release notes, http://processors.wiki.ti.com/index.php/RN_4_10_00_01, version 4.10.00.01 works for the Linux 3.8 kernel. From the release notes:
1. This release has been tested on AM parts only.
2. This release is build tested only for 387x(TI814x) & 389x(TI816x) & DM parts.
3. This release is build tested only against 3.8 kernel.
The BBB uses a 335x processor, not 387x or 389x - so it does not appear that it has been tested for the BBB, but it has been tested for the 3.8 kernel.
Also note that the above statement is contradicted later in the release notes by:
Kernel(Linux PSP) versions supported or used for validation
Please note that this release has been tested only on AM devices. No testing has been done on the DM parts. Only the following devices have been tested & details below -
AM335x - 3.2 kernel - http://arago-project.org/git/projects/linux-am33x.git- - AM335x Linux PSP 04.06.00.10
- Branch – v3.2-staging, TAG - v3.2_AM335xPSP_04.06.00.10-rc1, commit id -c8cce6279f5c126cbf6b6054f1ea0148bfc19511
AM35xx/AM37xx - 2.6.37 kernel- - Linux PSP Release : 04.02.00.07.
- Display drivers with DSS2 support ie, CONFIG_OMAP2_DSS=y
My assumption is that the earlier statement overrides the later statement.
To add to the confusion, many of these drivers are used in combination. For example, you might have both the Omap 2 Framebuffer Driver AND the SGX Driver installed. The SGX driver overrides some of the functions in the Omap driver(?). Xorg configuration would be for the Omap driver, not the SGX driver[?]
Please correct any of my misassumptions in the above.