Hi,
does anyone know, if it is possible to use SPI in U-Boot on a Raspberry Pi 3 Model B?
What I'm trying to achieve: - Connect a TPM 2.0 via SPI to the Raspberry Pi and communicate with it
What I already have: - Compiled U-Boot with support for Raspberry Pi 3 Model B; I can access the console and I can boot Raspbian from the SD-card
Questions / Problems: - How do I activate SPI support? I have enabled CONFIG_SPI, CONFIG_CMD_SPI and CONFIG_DM_SPI. I guess, I'd have also have to enable some Raspberry Pi specific SPI driver to make it work?
-> It seems like there is no driver for it, yet? (as far as I understand this: there would need to be a bcm2835 SPI driver, right?)
-> Would it be possible to alternatively use the SOFT_SPI driver (maybe that's also the easier way?)? (because it seems like one can access the GPIOs from U-Boot already, so that seems to be implemented) However, I can't find much about how this needs to be setup. BTW the U-Boot README references to the file "include/configs/sacsng.h" for an example, but that file doesn't exist anymore in the current master.
Thanks! Torben