commit 6d3c4c0922
Add terasic_mtl vt(4) framebuffer driver
terasic_mtl can be built with syscons(4) and vt(4) attachments, selected
at compile time.
commit 33240259b4
Clear terasic_mtl text buffer on attach
commit d188c2d241
Update terasic vt(4) driver for FreeBSD r269783
commit d1cc54eee8
Safety belt to ensure vt(4) fb parameters are correct
commit 76e6d468ef
Improve terasic_mtl_vt fdt parsing
- Use OF_getencprop to avoid need for explicit endian handling
(submitted by ray@freebsd.org)
- Check for expected length and correct pointer type
commit 3e2524b899
Correct device_printf usage
commit 9e53e3c8e0
Switch framebuffer to match host endianness
Xorg and xf86-video-scfb work much better with a native-endian
framebuffer.
commit 0f49259d59
Switch DE4 to vt(4) and enable kbdmux
commit 5bc96ebc89
Add missing \n in device_printf calls
Submitted by: emaste
Sponsored by: DARPA, AFRL
used with Terasic's DE-4 and other similar FPGA boards. This display
is 800x480 and includes a capacitive touch screen, multi-touch
gesture recognition, etc. This device driver depends on a Cambridge-
provided IP core that allows the MTL device to be hooked up to the
Altera Avalon SoC bus, and also provides a VGA-like text frame buffer.
Although it is compiled as a single device driver, it actually
implements a number of different device nodes exporting various
aspects of this multi-function device to userspace:
- Simple memory-mapped driver for the MTL 24-bit pixel frame buffer.
- Simple memory-mapped driver for the MTL control register set.
- Simple memory-mapped driver for the MTL text frame buffer.
- syscons attachment for the MTL text frame buffer.
This driver attaches directly to Nexus as is common for SoC device
drivers, and for the time being is considered BERI-specific, although
in principle it might be used with other hard and soft cores on
Altera FPGAs.
Control registers, including touchscreen input, are simply memory
mapped; in the future it would be desirable to hook up a more
conventional device node that can stream events, support kqueue(2)/
poll(2)/select(2), etc.
This is the first use of syscons on MIPS, as far as I can tell, and
there are some loose ends, such as an inability to use the hardware
cursor. More fundamentally, it appears that syscons(4) assumes that
either a host is PC-like (i386, amd64) *or* it must be using a
graphical frame buffer. While the MTL supports a graphical frame
buffer, using the text frame buffer is preferable for console use.
Fixing this issue in syscons(4) requires non-trivial changes, as the
text frame buffer support assumes that direct memory access can be
done to the text frame buffer without using bus accessor methods,
which is not the case on MIPS. As a workaround for this, we instead
double-buffer and pretend to be a graphical frame buffer exposing
text accessor methods, leading to some quirks in syscons behaviour.
Sponsored by: DARPA, AFRL
