Hi,
Documentation here, for boot flow:
https://www.raspberrypi.com/documentati ... t-sequence
Includes the tease: "If enabled: check SPI" -- with no further details.
Later, among the Notes, there is:
"NAND boot and SPI boot modes do work, although they do not yet have full GPU support."
And, noting that Pi5 is a BCM2712 device, there is this:
https://www.raspberrypi.com/documentati ... 12-devices
Which further teases: "Bit 11: Disable booting from SPI"
Is there any further detail about what this SPI boot means?
For example: How would one practically boot a Pi5 over SPI? Which pins are checked? What data structure is to be transferred? What does the caveat "not yet have full GPU support" amount to? What does the GPU have to do with booting anyway? Etc.
Any pointers welcome!
Bill
Documentation here, for boot flow:
https://www.raspberrypi.com/documentati ... t-sequence
Includes the tease: "If enabled: check SPI" -- with no further details.
Later, among the Notes, there is:
"NAND boot and SPI boot modes do work, although they do not yet have full GPU support."
And, noting that Pi5 is a BCM2712 device, there is this:
https://www.raspberrypi.com/documentati ... 12-devices
Which further teases: "Bit 11: Disable booting from SPI"
Is there any further detail about what this SPI boot means?
For example: How would one practically boot a Pi5 over SPI? Which pins are checked? What data structure is to be transferred? What does the caveat "not yet have full GPU support" amount to? What does the GPU have to do with booting anyway? Etc.
Any pointers welcome!
Bill
Statistics: Posted by BillEllis — Wed Oct 01, 2025 1:30 pm — Replies 3 — Views 135