Is there support for DPI?

[rocinante-sys]

rPi supports RGB LCD panels via their GPIO0 bank pins. Would this be hard to add if not supported yet?

I've been playing with the idea of making this (piCore):

It's a small SoM with BCM2835 and I would need custom firmware as the broadcom license does not allow to run their firmware on anything but official rPi HW.

What I need is eMMC, USB, SPI, I2C and DPI working. Which of these would I need to implement on my own to make it work?

[cleverca22]

DPI is one of the first video outputs i tested when figuring out the video subsystem but i didnt have a screen at the time, so i was only generating a 100x100 pixel image, and then watching only one bit of the color from a scope

i have since gotten a hyperpixel screen, but it has an init sequence that has to run first, and i havent tested that out yet

https://github.com/librerpi/lk-overlay/blob/master/platform/bcm28xx/dpi/dpi.c

this is the code i was last using for DPI

you can also find me in #raspberrypi-internals on libera if you want a more realtime chat

[rocinante-sys]

Thanks!

I'll test this out as I'm just soldering together a simple rPi zero DPI hat and I have a 24bit 800x480 LCD for testing. I'll hop on the chat too :)

[cleverca22]

https://github.com/librerpi/lk-overlay/blob/9eb5d65e0da8ac737e44ddda88df96ef613641b6/platform/bcm28xx/dpi/dpi.c#L26-L50

my latest code can now drive a VGA monitor over DPI using the gertvga adapter board

it will automatically compute the divisors needed to hit the target fps, based on the supplied timing parameters

usb-host already works in linux SPI/i2c should just work, but ive only tested i2c the sdhost controller works 90% of the time, ive not bothered checking with sdhci since that would be claimed by wifi normally, but it is an option