You can download the latest UEFI build by clicking the Azure Pipelines icon below. Click Artifacts button in Azure Pipelines, then download UEFI.elf in ELF directory.

This package demonstrates an AArch64 UEFI implementation for hacked Lumia 950 and Lumia 950 XL. Currently it is able to boot Windows 10 ARM64 as well as various Linux distros. See notes below for more details. Please be aware that MSM8992 devices have limited support.

Hapanero support has been dropped as of 2020/11. Hapanero users are expected to completely understand all hardware, firmware and software implementation details, thus there's no point to keep an untested target floating in this project. For existing Hapanero owners, please build and fix this firmware by yourself (use 950 XL configuration as the blueprint), but no PR regarding Hapanero will be accepted.

Applicable to all supported targets unless noted.

• Low-speed I/O: I2C, SPI, GPIO, SPMI and Pinmux (TLMM).
• Power Management: PMIC and Resource Power Manager (RPM).
• High-speed I/O for firmware and HLOS: eMMC (SDR50 in firmware, HS200/HS400 in OS) and microSD (be aware that a few cards are unsupported), PCI Express (Firmware-configured, HLOS Only, x2 Lane)
• Peripherals: Touchscreen (QUP I2C), side-band buttons (TLMM GPIO and PMIC GPIO) and Lattice UC120 (iCE5LP2K) FPGA configuration
• Display FrameBuffer depends on stock Qualcomm UEFI for boostrapping, MDP is not fully implemented.

I am too busy to write an average-user tutorial. So, if you are interested in, you are welcome to contribute to an easy instruction for all Lumia 950 (XL) users.

Or you can buy me a coffee: PayPal.

If you are familiar with EDK2, you don't need to use my build script.

• Checkout a copy of EDK2. We are currently tracking the master branch. At least commit 1b6b4a83e1d85e48837068dfe409f5557b50d71d works without further modification.
• Checkout this repository under EDK2's worktree.
• Install ACPI tools from your package manager or ACPICA website.
• Install uuid-dev and python (or equivalent package on your distribution).
• Install Linaro AArch64 GCC toolchains, my build script uses gcc-linaro-7.5.0-2019.12. Then untar them. I place everything under /opt directory, so I have directories like /opt/gcc-linaro-7.5.0-2019.12-x86_64_aarch64-elf/bin. If you placed it somewhere else, modify build scripts. If you are macOS user, bootstrap the toolchain using ct-ng.
• Run EDK2 BaseTools setup (make -C BaseTools).
• Copy rundbbuild.sh in Tools directory to your EDK2 worktree root directory.
• By default only MSM8994 target is built. To build all, set environment variable BUILDALL.
• Start build: . rundbbuild.sh --950xl --development

If you checked out the EDK2 repository under Windows and build it using WSL, you will have trouble locating BaseTools Python classes due to file case sensitive behavior changes in WSL. Run the following PowerShell script under EDK2 directory prior to build:

Get-ChildItem .\BaseTools\ -Directory -Recurse | Foreach-Object { fsutil.exe file setCaseSensitiveInfo $_.FullName }

You only need to run it once.

Per UEFI specification, ARM32 UEFI cannot boot ARM64 binaries directly. A recent engineering change removed the dependency of Little Kernel. LK can still boot it, but the path is untested.

To run this UEFI build on Lumia 950 XL, the following procedure is required:

• Check out Boot Shim. This Boot Manager Application implements a simple ELF loader for the kickstarter (LK) with Secure Monitor Call for EL1 transition. You will need branch msm8994-aa64.
• Place UEFI.elf in the WP EFIESP root directory, copy Boot Shim EFI application to the EFIESP partition, create a new BCD entry for it.
• Select this boot entry to enter UEFI.

To re-flash UEFI, simply place new UEFI.elf in WP EFIESP root directory.

Qualcomm Snapdragon MSM8992/MSM8994 implements a subset of PSCI interface for multi-processor startup. However, required commands like PSCI_SYSTEM_OFF and PSCI_SYSTEM_RESET are not implemented. Hence we use PMIC to shutdown platform (there's a bug in RT that will be fixed) instead of PSCI. Additionally, 8992/8994 uses HVC call for PSCI commands instead of SMC call.

The ACPI tables are copied from stock Windows Phone FFU, hence these device IDs are likely not be recognized by Linux.

To get started, starts with the device tree of Qualcomm MSM8994 MTP. The repository devicetree-rebasing with DT content from Android Linux Kernel is sufficient for DT development. To boot with device tree, add it in your GRUB configuration:

devicetree /lumia-950-xl.dtb
linux /vmlinuz ..... acpi=no

PSCI partially works in EL1. If you want to use PSCI for multi-processor startup, add the following code to your DT:

psci {
	compatible	= "arm,psci-0.2";
	method		= "hvc";
};

And use psci for core-enable method. If you are using EL2 startup, use spin-table with per_cpu_mailbox_addr + 0x8 as the release address.

For MSM8994, PCI Express Root Port 1 is firmware-initialized. Similarly, MSM8992 have PCI Express Root Port 0 initialized. Hence it is not necessary to supply qcom,pcie in device tree. Instead, supply a firmware-initialized PCI bus device pci-host-ecam-generic. ACPI MCFG table is supplied for your reference.

Note: interrupt is not configured in the example below (therefore ath10k will crash the system if loaded.)

pci@f8800000 {
	compatible = "pci-host-ecam-generic";
	device_type = "pci";
	#address-cells = <0x3>;
	#size-cells = <0x2>;
	bus-range = <0x0 0x1>;
	#interrupt-cells = <0x1>;

	reg = <0xf8800000 0x200000>;
	ranges = <0x02000000 0x0 0xf8a00000 0xf8a00000 0x0 0x600000>;

	status = "okay";
};

• EFIDroid Project
• Andrei Warkentin and his RaspberryPiPkg
• Sarah Purohit
• Googulator

All code except drivers in GPLDriver directory are licensed under BSD 2-Clause. GPL Drivers are licensed under GPLv2 license.