Hi Tom, On Thu, 17 Apr 2025 at 15:24, Tom Rini <tr...@konsulko.com> wrote: > > On Thu, Apr 17, 2025 at 12:15:42PM -0600, Simon Glass wrote: > > > This series adds a standard way of passing information between different > > firmware phases. This already exists in U-Boot at a very basic level, in > > the form of a bloblist containing an spl_handoff structure, but the intent > > here is to define something useful across projects. > > > > The need for this is growing as firmware fragments into multiple binaries > > each with its own purpose. Without any run-time connection, we must rely > > on build-time settings which are brittle and painful to keep in sync. > > > > This feature is named 'standard passage' since the name is more unique > > than many others that could be chosen, it is a passage in the sense that > > information is flowing from one place to another and it is standard, > > because that is what we want to create. > > > > The implementation is mostly a pointer to a bloblist in a register, with > > an extra register to point to a devicetree, for more complex data. This > > should cover all cases (small memory footprint as well as complex data > > flow) and be easy enough to implement on all architectures. > > > > The emphasis is on enabling open communcation between binaries, not > > enabling passage of secret, undocumented data, although this is possible > > in a private environment. > > > > This series is available at u-boot-dm/pass-working > > Before I get into further feedback, my first bit of feedback is that > this breaks transfer list support. I didn't check this on Raymond's QEMU > but did test it on vexpress_fvp_bloblist and expect QEMU is also broken. > The most likely reason I think is: > > passage: spl: Support passing the passage to U-Boot > [snip] > > xferlist: Drop old xferlist code
CI passes for me: https://source.denx.de/u-boot/custodians/u-boot-dm/-/pipelines/25806 > > These are not the same. And they should be. And they should be using > the register layout / values other projects use today. > > And I am bluntly uninterested in who shuffled the registers around and > made them no longer agree. What TF-A is doing now is what's in the wild > now. And shame on them if there wasn't a good reason for changing things > either. They are the same and any difference is a bug, quite possibly in my code. I am hoping that Raymond can point it out, as I believe I am following the spec that we created. The xferlist is a little harder to maintain and it has a bit of an unusual API. It's better to use global_data for this case. Regards, Simon
