EOI in getting SPI going on the RPi5

Looking for the more advanced programmers interested in getting the RPi5 SPI driver going. And those with RPi5 and Mesa 7c80 7c81 hardware willing to test.
If needed I can supply 7c81 type spi firmware for Spartan6 dev boards or the colorlight RV901 for testing purposes (tho some hardware hacking maybe involved for the RV901).

We need to mash this file into our drivers, as this is the new RPi5 spi driver
github.com/raspberrypi/linux/blob/rpi-6....rs/spi/spi-dw-mmio.c

RPi5 doesnt use the same broadcom IO stuff as previous models, they made a their own IO chip. instead of bcm2835 controlling the SPI, the new chip used this designware driver

I've mentioned this, probably like a broken record. Mentioned it on git, around late Nov early Dec when I got my RPi5 but no response.

The whole RP1 thing has been a headache for a lot of gpio libraries, and no warning prior to release. Tho I guess if they mentioned this sales may have tanked.

Does the following help?

github.com/praktronics/rpi5-rp1-spi
"Write some data to, and read some data from a slave device using the registers, rather than spi-dev"

(I have very limited understanding of this stuff)

I have been working (playing) with Rpi5 and Bookworm with preempt_rt. I have preempt_rt running on RPi4 and RPi5 (separate compiles). The RPi4 uses bcm2711_defconfig while the RPi5 uses bcm2712_defconfig. I have kernel version 6.6.20-rt25-v8 (-4k+ on the RPi4) and (-16k+ on the RPI5).
In the last couple of weeks they have added support for spi CS for additional cs pins. I am currently running the kernel on Raspian Bookworm but I have previously used the same sources to compile kernels on straight debian. If anyone is interested, I will put my sources up on my GitHub.
For awhile I was having difficulty getting the kernels to load but now I seem to have the process down. I will try shortly loading the kernel on the linuxcnc image for RPi5 to verify that the same kernel will run on both debian and raspian bookworm.

Great find pip

Tho I did try
"Write some data to, and read some data from a slave device using the registers"

But couldn't get this line to compile

acondit wrote:

I have been working (playing) with Rpi5 and Bookworm with preempt_rt. I have preempt_rt running on RPi4 and RPi5 (separate compiles). The RPi4 uses bcm2711_defconfig while the RPi5 uses bcm2712_defconfig. I have kernel version 6.6.20-rt25-v8 (-4k+ on the RPi4) and (-16k+ on the RPI5).
In the last couple of weeks they have added support for spi CS for additional cs pins. I am currently running the kernel on Raspian Bookworm but I have previously used the same sources to compile kernels on straight debian. If anyone is interested, I will put my sources up on my GitHub.
For awhile I was having difficulty getting the kernels to load but now I seem to have the process down. I will try shortly loading the kernel on the linuxcnc image for RPi5 to verify that the same kernel will run on both debian and raspian bookworm.

There is no issue with kernels or images that can run Linuxcnc on the RPi 5. That had been sorted wayback in Nov\Dec.
The issue is due to the RP1 the RPi4 driver is not compatible with RPi5. It doesn’t matter what changes are made to the kernel the current hm2-rpspi driver can’t be used with the RPi5. A new driver needs to be written to suit the new hardware.
The whole point of this thread was to try and generate some interest, which hasn’t really happened. So it would seem there are other priorities, so patience is the key.
Spidev is not the answer, I have tried and the speed in the context of a servo thread isn’t there.

Super!! I'm enthusiastic! I have a PI5 doing nothing and a 7C80 (now working with a PI4). The PI5 is sooooo much faster, so I would like to use my 5 with my SPI-interface-mesa-card.

I'm not a programmer, but I can test things on a real machine. I might give you acces to it, if that is helpful... (while keeping the motors off )
 

How do I use spi on the rpi5, spidev hasn't been updated since 2022, before the rpi5 came out. Ive used spidev and it works half the time, but also get threading errors.