2021 Amlogic SoCs Features Status

[Martin Blumenstingl]

Hi Neil,

thank you for this summary!

On Thu, Apr 15, 2021 at 4:29 PM Neil Armstrong <narmstrong at baylibre.com> wrote:
[...]
> I would like to thanks all the contributors (code, test, bug reports, ...) for the last
> 4,5 years !
Indeed, thanks to everyone who helped to get where we are right now!

[...]
> ## Meson6 / Meson8 / Meson8b
>
> I'll let martin elaborate on that, but it seems the biggest missing bits are Display, Video Decoder & Encoder support.
Meson6: unknown status, I don't have any hardware so YMMV
Meson8: similar status as Meson8b/Meson8m2 as these SoCs are almost
identical. The only known differences are Ethernet (Meson8 and Meson6
use the same Ethernet IP, while Meson8b and Meson8m2 use a newer IP ->
same as found on GXBB) and some clocks (which means that Meson8 cannot
change the GPU clock at runtime for example because the glitch-free
mux is absent)

Meson8b/Meson8m2:
video output:
1. I need to re-spin and re-test my CCF series which makes the video
clock tree mutable. This means I need to use the PLL initialization
"magic registers" to set the PLL to the "doubling" mode
2. some of the existing DRM driver code needs to be converted to a
bridge so I don't have to duplicate the non-dw-HDMI part of
meson_dw_hdmi.c
3. 1080P and lower video modes are working with my out-of-tree driver
for me. upstreaming this driver will require multiple rounds of
reviews as this includes a driver for the TransSwitch HDMI controller
IP (not just the Amlogic part)
4. cleanup of the DRM patches sitting in my tree

HDMI CEC:
- untested, but I hope that it's similar enough to GXBB so it works
without too much effort

audio output:
- in my tests SPDIF output is working fine
- I2S over HDMI also worked "fine" in my (2-channel) tests. I expect
that it'll suffer from the MGN issue as GXBB, GXL and GXM
- for boards where the analog output path is known this can be made to
work. I did some experiments on my EC-100 some time ago where I could
get it to work. but I was unsuccessful with the analog out on other
boards

video encoders/decoders:
- according to what Maxime told me some time ago this should be very
similar to GXBB but I have not done any experiments so far

once implemented for any of Meson8/Meson8b/Meson8m2/GXBB we'll get it
for the "other" SoCs for free:
- IR hardware decoding
- USB OTG


Best regards,
Martin