I have reinstalled a Kedei v6.2 last week using
but this should also work:
http://kedei.net/raspberry/v6_1/rpi_35_ ... _15_18.rar
No need to download/install the LCD-Show thing; it's completely useless. Just write the image on the uSD, and boot it.
Not sure if I am using a pi2 or 3, but it does not matter, both should be the same. So if the Osoyoo does not work, take the Kedei. Osoyoo works for me. The Kedei seems to include a more recent kernel.
I don't use official Raspbian image with Kedei LCDs, because KeDei images are certified to work, and ... do work out of the box.
LCD_show_v6_1_3.tar.gz can not work on raspbian images; it's impossible. Your steps are doomed to fail.
Raspbian and Kedei are very similar, but, completely uncompatible; Kedei heavily patches the kernel, and assumes many system libs are fixed versions; they disable many features (like I2C), and prevent installation of some tools. LCD-show does not have the guts to work on official Raspbian. Many things break with Kedei images (several wrapers, modules and overlays are disabled.
It's possible to get Kedei LCDs working with an official raspbian, using the tutorials I gave on march 31st: some Kedei LCDs can work on Orange Pis, using the Notro method. So, this Notro method *MUST* succeed on rpi, with any official Raspbian image. But you have to spend a few hours on it. And Notro won't work with all KeDei, because they have at least 3 or 4 different pinouts (the hardware version is not written to decorate the back face; they are completely different down to the pinout).
If you got it work nevertheless, maybe they have fixed their LCD-show tool, and maybe recent versions can do it now; but 3 years ago, it was no-go.
It is probably possible to use the two display outputs at the same time using the Notro method.
High end consumers, and business rarely buy SPI LCDs, and, won't buy KeDei because they are not reliable. There are many better SPI monitors by other manufacturers which work much better ... for the same price. I have found SPI LCDs on Ali at the same price (around 8€) which work fine on OrangePis via Notro. For sure they can work as well on rPi !!! And, as big advantage, they are provided with pinout, letting you know how to configure Notro ... while Kedei never published any pinout, and geeks had to reverse engineer them to find how to drive them manually. KeDei can be used with the Notro method, but it's poorly documented (some people provide working commands on forums, but, without telling their hardware version; if they are using an LCD v3, it won't work for you when you have a v6).
I never used that method; they say they are using a v6.2, and you say you are using also a 6.2, so, their tuto should work.
Since they provide a pinout, you can use the Notro method. Install the Notro repo, follow the tutorial, and adjust the boot options according to your pinout.
SPI is uncompatible with DRI; forget it. DRI is hardware acceleration; SPI is 100% software video driver. There may be workarounds, but the Pis are probably too weaks to run them in real time; especially Raspberries; some versions of Oranges have huge CPUs (2 to 4 times better than a Raspberry at the same price), and may be able to sort it out in real time; but those powerfull boards are costy (there are oranges up to 45€). DRI emulation may involve very heavy software like
https://www.x.org/archive/X11R7.5/doc/m ... est.1.html
(curious people may also want to read about Xephyr, but it's offtopic for Panchon ).