Am 05.07.24 um 23:14 schrieb Lukas Wunner:
On Fri, Jul 05, 2024 at 12:16:14PM -0500, Jeremy Linton wrote:
Am 05.07.24 um 17:03 schrieb Lukas Wunner:
Careful there, the patch vaguely says...
With that added and identified as "BCM2848",
an id in use by other OSs for this device, the dw2
controller on the BCM2711 will work.
...which sounds like they copy-pasted the BCM2848 id from somewhere else.
I would assume that BCM2848 is really a different SoC and not just
a different name for the BCM2835, but hopefully BroadCom folks will
be able to confirm or deny this (and thus the necessity of the quirk
on BCM2848 and not just on BCM2835).
This id comes from the edk2-platforms ACPI tables and is currently used by
both the rpi3 and rpi4, and AFAIK nothing else as the rpi5-dev work is
currently only exposing XHCI.
The ID is strictly the USB controller not the SoC. Its a bit confusingly
named, but something we inherited from the much older windows/edk2 port,
where it appears that the peripheral HID's were just picked in numerical
order.
[0] https://github.com/tianocore/edk2-platforms/blob/12f68d29abdc9d703f67bd743fdec23ebb1e966e/Platform/RaspberryPi/AcpiTables/GpuDevs.asl#L15
So BCM2848, BCM2849, BCM2850 and so on are just made-up IDs
for a Windows/EDK2 port that got cargo-culted into the kernel?
Yikes!
Has anyone checked whether they collide with actual Broadcom products?
Using public available information like this [1], I wasn't able to find
any collision.
[1] - https://github.com/anholt/linux/wiki/Devices-with-Videocore-graphics
