adaptation-a64

These are the Phorepoc OS drivers for the Allwinner A64 system-on-chip. They cover the display, the Mali-400 GPU, the video decoder, the camera interface, the sensors, USB and Wi-Fi.

Nothing here is specific to one device, so any A64 board can use it. A board repository names this one in its board.conf.

What's in here

os/src/phorepoc-arm/a64/    the chip's drivers
os/src/phorepoc-arm/mali/   the Mali-400 GPU kernel driver
os/src/phorepoc-arm/vde/    the video decoder driver
os/src/<component>/         programs and tests that use these drivers (phevdec, phecam, phfs, ssya64 and others)
registry/components_a64.py  the components this repository adds

The screen recorder

os/src/pherec/ (pherec.exe) records the screen for PhoneLab's record_start / record_stop: it captures what the user sees through the debug link's capture channel, skips unchanged pictures and keeps H.264 records in a ring PhoneLab polls. The H.264 encoder itself (os/src/pherecenc/, the video engine's hardware encoder) is patent-encumbered, so it is never in an image: it is this repository's Catalogue package screenrec-a64 (package.conf, recipes/sis.sh). Without it the recorder refuses to record and PhoneLab says to install it.

At build time os/ is laid over core's os/, so the paths line up with core's.

Building

You don't build this repository by itself. Check it out next to core, the pdk, a board repository that names it and mesa-symbian, and build the image as the pdk README describes. The board's board.conf brings this repository in.

What the board provides

The wiring of a board is the board's. The panel, its backlight and the PMIC rails are functions the board implements (a64_board.h, in the board's board/kernel/). Pin numbers, the touch controller's bus and address, the USB product string and the sensor location are macros in the board's board/kernel/a64_board_config.h; the code here stops the build with an #error if one is missing. a64_glue.cpp takes the LED and vibrator pins, a64uart.cpp the modem's control pins, a64touch.cpp the touch wiring, a64_usbcc.cpp the product string and ssya64 the sensor location. The Bluetooth UART's pins in a64uart.cpp are still fixed numbers here.

Code from Linux

Two drivers started from Linux code that's offered under a choice of licenses, and we use the permissive one:

• The Wi-Fi driver in os/src/phorepoc-arm/a64/wlan/rtw88/ is Linux's rtw88, used under BSD-3-Clause.
• The GPU scheduler in os/src/phorepoc-arm/mali/mali_ldd.cpp comes from Linux's lima driver, used under MIT.

One thing we can't ship is the table of coefficients the display scaler uses, because the only source we know of is GPL-only. Without it, video at its own size looks right, and scaled video is a bit soft.

License

Code we wrote, and Symbian files we've changed, are EPL-2.0, with GPL-2.0-or-later as a Secondary License, and Symbian files we use unchanged stay EPL-1.0. The code from Linux keeps the license named above. The license texts are in LICENSES/.

Contributions are welcome under the same terms. Add your name to AUTHORS in your first pull request.