New Pi Foundation BCM2711 docs!

Thanks to a tip from user clever in our Discord channel (#rpi4-uefi-dev), I just found out one of the Pi Foundation engineers and forum moderators, jamesh, posted something cool:

Enjoy this extensive read during the current crisis! It’s a major update to the original 2835 datasheet, with a lot more information. If you find any problems, please comment on this thread.

https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=270102

https://www.raspberrypi.org/documentation/hardware/raspberrypi/bcm2711/rpi_DATA_2711_1p0.pdf

This doc is for the SoC in the Pi 4B. I personally haven’t read through it yet, but glancing at the table of contents I see there are many goodies here. Hooray for not having to look at Pi 4B DTS (device tree) sources as documentation! 😇

Linaro Tech Days talk on Pi UEFI

Originally Samer and I were going to present the ongoing Raspberry Pi 4B UEFI work at Linaro Connect ’20 in Budapest. Of course, life had its own plans, but fortunately Linaro was gracious and accommodating to host a virtual event and invite us to be a part of it.

https://connect.linaro.org/resources/ltd20/ltd20-207/

We briefly talked about ServerReady and standardization of the server parts, mentioned the difficulties seen with current non-server parts like the Pi, described the approach taken, provided a status update on where the UEFI/ACPI “ServerReady”-like firmware is today, and left the audience with a call to action to both join the community effort and help beyond the Pi with some other devices, like Rockchip and nVidia-based platforms. Had some good questions from the audience, too.

The full video presentation is available on Youtube, and slides are over at LTD20 207 Making Pi ServerReady.

v1.7 – yes, only a day after v1.6.

I hadn’t even finished writing up the 1.6 related artifacts when Pete pushed the button on the new release. Huge thanks both to Pete for getting this out there so soon and to Ard Biesheuvel for reviewing and approving the edk2-platforms fixes.

https://github.com/pftf/RPi4/releases/tag/v1.7

What’s inside this release?

The ACPI fixes will mean improved hardware support in OSes, although today that mostly means improved NetBSD support. We definitely need some volunteers to help with enabling Pi 4 support with ACPI in upstream Linux – see the issue tracker.

Big shout-out to Jeremy Linton for the PPTT implementation (Processor Properties Topology Table) – a new ACPI 6.3 table describing the relation between CPUs and caches. Yes, that’s not a typo – our PPTT is the 2nd revision variant introduced in ACPI 6.3, whereas PPTT was first introduced in 6.2.

Note: the matching Pi 3 UEFI release (v1.19) combines the fixes for the Pi 4 v1.6 and v1.7 releases.

As always, read the release notes and usual caveats.

v1.6 out

A few more goodies…

https://github.com/pftf/RPi4/releases/tag/v1.6

What’s inside this release?

Biggest change here is that your Pi will now boot at the default (Pi Foundation-recommended) frequency, instead of the 600MHz minimum. One less configuration option to change on every upgrade!

IMPORTANT: HTTP(S) boot, like PXE and iSCSI, will not currently work with the internal network card, because the GENET driver has not been upstreamed yet. This means you need a supported USB interface (Ax88772b) to use this feature.

As always, read the release notes and usual caveats.

More GENET work

Our UEFI firmware already supports certain USB-based network adapters for network booting (or other purposes), but that requires an additional adapter, which becomes even more awkward if you want to use a PoE HAT. NetBSD Arm platform guru Jared McNeill has been working on something, that Pi 4 UEFI users are going to find pretty cool. Dongle-less PXE and iSCSI is coming to a Pi 4 near you, because we’re getting native support for GENET networking soon! 😍🔥

This is being implemented as a Simple Network Protocol driver, so it will be usable by any UEFI driver or application.

v1.5 release available

A quick follow-up to v1.4, this release brings some important fixes.

Don’t stop me now (’cause I’m having a good time)
Don’t stop me now (yes, I’m havin’ a good time)
I don’t want to stop at all

Queen – Jazz

https://github.com/pftf/RPi4/releases/tag/v1.5

What’s inside this release?

This release mostly improves on the logic added to v1.4 release for switching between 3GB/4GB modes on the 4GB Pi 4.

Now, when you have 3GiB mode selected (which is the default), you will see 3GiB being reflected in the UEFI setup screen.

The fix for external .dtb is worth diving into. Many of our readers will know, that Raspberries traditionally boot operating systems with Device Tree, instead of ACPI. A dated overview can be found on the official Pi site. Long story short, if you want to boot an 64-bit Linux, NetBSD or FreeBSD today on the Pi with full I/O support, you still need the Device Tree that the VPU firmware prepares based on your config.txt settings (dtparams, overlays, etc).

The Pi 4 support for Device Tree is exactly like the Pi 3 support. At the time, UEFI relied on the Device Tree being placed in RAM after the UEFI image itself, basically overlaying itself on a section of the UEFI image. Recently, new VideoCore firmware broke this approach (which I really shouldn’t have come up with in the first place!) by switching the load ordering – now the Device Tree was loaded before the UEFI image, and since the two images overlapped, the Device Tree blob was getting overwritten. You can read more about it here and here. Anyway, it’s fixed now. The same fix needs to be made to the Pi 3 build. That’s still TBD.

If you want to boot an OS using Device Tree, don’t forget to enable it. By default the Pi 4 will boot in ACPI mode.

Be mindful that the fix involved changing the load address for the Device Tree in a way that wouldn’t overlap the UEFI image. The new values are:

  • device_tree_address=0x1f0000
  • device_tree_end=0x200000

While looking at the above regression, we were also able to regain 2MiB of memory, as the Trusted Firmware footprint for Pi 4 is much smaller than on the Pi 3.

As always, read the release notes and usual caveats.

v1.4 release already out

Pete’s on a roll! Some significant improvements have landed in the latest and greatest release.

https://github.com/pftf/RPi4/releases/tag/v1.4

What’s inside this release?

Assuming you have a 4GiB Pi, you can now boot with with the entire 4GiB available if you run NetBSD-current (generic 64-bit image), which already supports the ACPI interfaces required to make the Pi USB3 controller work with the full 4GiB RAM. Those living on the edge can try this Linux patch.

Note: upstreaming the Linux patch would be a great way to help this project.

Additionally, there’s been some improvements to the setup option layout:

Reorder forms in the order they are most likely to be queried.
Rename Chipset Configuration, making CPU settings more prominent.
New Advanced Configuration. 3GB limit setting is grayed out on 1GB/2GB boards.
Grouping all SD/MMC settings together.

As always, read the release notes and usual caveats.

v1.3 release

This is a minor follow-up to v1.2 for Pi 4, intended to do some soak testing on the ongoing ACPI clean-up and factorization changes.

https://github.com/pftf/RPi4/releases/tag/v1.3

What’s inside this release?

As always, read the release notes and usual caveats.

Updates to the status page!

Based on feedback in the Discord channel (thanks Samer!) I reworked the status page to scale better across future releases and provide more information in an easier-to-consume fashion.

Not only does the new version aggregate all of the release notes, but provides an easy way for locating firmware feature, development status, OS support and standards compliance reports for every new release. All of the OS and firmware status reports will be per release, meaning you will be able to reference old reports if needed.

Finally, the new reports link back to the issue tracker and we have our first set of ACS compliance reports now too.

The updated project status page.