On 07/26/2011 01:24 PM, Koen Kooi wrote:
Note that framebuffer and display are 2 completely seperate things. The framebuffer is just a portion of RAM linux will draw into, getting that out onto a display is something else.
Yep.
And I am happy for this, as in the end I want to design an embedded device that does not have a display but the framebuffer is just a chunk of memory (to be viewed via VNC only when desired). But I think, that for development a physical display can be beneficial and thus I want to do the first steps using one and stick with the "standard" ways.
I understand that (with the OMAP chip that does not have any graphic-"accelerator" hardware), the "framebuffer" Kernel driver allocates a chunk of memory when loaded and allows the Xorg server to write and read to same via the /dev/fs device. The driver also makes the chip's DMA hardware read the framebuffer memory to create a visible output on the LCD (or video screen)
In the end I'd like to modify the (or find a modified) framebuffer Kernel driver in a way that I (at best at runtime) can switch off the display and disable the DMA (and with it the non-cacheable feature of the FB's RAM area). With that I hope to increase the performance.
What do you think ? -Michael _______________________________________________ Angstrom-distro-devel mailing list Angstrom-distro-devel@linuxtogo.org http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/angstrom-distro-devel