Merge patch series "Implement ACPI on aarch64"

Patrick Rudolph <[email protected]> says:

Based on the existing work done by Simon Glass this series adds
support for booting aarch64 devices using ACPI only.
As first target QEMU SBSA support is added, which relies on ACPI
only to boot an OS. As secondary target the Raspberry Pi4 was used,
which is broadly available and allows easy testing of the proposed
solution.

The series is split into ACPI cleanups and code movements, adding
Arm specific ACPI tables and finally SoC and mainboard related
changes to boot a Linux on the QEMU SBSA and RPi4. Currently only the
mandatory ACPI tables are supported, allowing to boot into Linux
without errors.

The QEMU SBSA support is feature complete and provides the same
functionality as the EDK2 implementation.

The changes were tested on real hardware as well on QEMU v9.0:

qemu-system-aarch64 -machine sbsa-ref -nographic -cpu cortex-a57 \
                    -pflash secure-world.rom \
                    -pflash unsecure-world.rom

qemu-system-aarch64 -machine raspi4b -kernel u-boot.bin -cpu cortex-a72 \
-smp 4 -m 2G -drive file=raspbian.img,format=raw,index=0 \
-dtb bcm2711-rpi-4-b.dtb -nographic

Tested against FWTS V24.03.00.

Known issues:
- The QEMU rpi4 support is currently limited as it doesn't emulate PCI,
  USB or ethernet devices!
- The SMP bringup doesn't work on RPi4, but works in QEMU (Possibly
  cache related).
- PCI on RPI4 isn't working on real hardware since the pcie_brcmstb
  Linux kernel module doesn't support ACPI yet.

Link: https://lore.kernel.org/r/[email protected]

3 files changed, 100 insertions, 0 deletions

diff --git a/doc/board/emulation/index.rst b/doc/board/emulation/index.rst
index 98a0b26ad24..0419d724150 100644
--- a/doc/board/emulation/index.rst
+++ b/doc/board/emulation/index.rst
@@ -13,5 +13,6 @@ Emulation
    qemu-mips
    qemu-ppce500
    qemu-riscv
+   qemu-sbsa
    qemu-x86
    qemu-xtensa
diff --git a/doc/board/emulation/qemu-sbsa.rst b/doc/board/emulation/qemu-sbsa.rst
new file mode 100644
index 00000000000..fe1dc3249e4
--- /dev/null
+++ b/doc/board/emulation/qemu-sbsa.rst
@@ -0,0 +1,98 @@
+.. SPDX-License-Identifier: GPL-2.0+
+.. Copyright (C) 2024, Patrick Rudolph <[email protected]>
+
+QEMU ARM SBSA
+=============
+
+QEMU for ARM supports Arm Server Base System Architecture Reference board,
+short 'sbsa-ref' that utilizes ACPI over FDT. This document describes how to run
+U-Boot under it. Only AArch64 is supported.
+
+The 'sbsa' platform provides the following as the basic functionality:
+
+    - A freely configurable amount of CPU cores
+    - U-Boot loaded and executing in the emulated flash at address 0x10000000
+    - No device tree blob
+    - A freely configurable amount of RAM
+    - A PL011 serial port
+    - An ARMv7/ARMv8 architected timer
+    - PSCI for rebooting the system
+    - A generic ECAM-based PCI host controller
+
+Additionally, a number of optional peripherals can be added to the PCI bus.
+
+Compile ARM Trusted Firmware (ATF)
+----------------------------------
+
+Get and Build the ARM Trusted firmware
+--------------------------------------
+
+Note: srctree is U-Boot source directory
+Get ATF from: https://github.com/ARM-software/arm-trusted-firmware
+
+.. code-block:: bash
+
+  git clone https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git tfa
+  cd tfa
+  make CROSS_COMPILE=aarch64-linux-gnu- all fip \
+    ARM_LINUX_KERNEL_AS_BL33=1 DEBUG=1 PLAT=qemu_sbsa
+
+Copy the resulting FIP and BL1 binary
+
+.. code-block:: bash
+
+  cp build/qemu_sbsa/debug/fip.bin ../
+  cp build/qemu_sbsa/debug/bl1.bin ../
+
+Building U-Boot
+---------------
+Set the CROSS_COMPILE environment variable as usual, and run:
+
+.. code-block:: bash
+
+    make qemu-arm-sbsa_defconfig
+    make
+
+Running U-Boot
+--------------
+The minimal QEMU command line to get U-Boot up and running is:
+
+.. code-block:: bash
+
+    qemu-system-aarch64 -machine sbsa-ref -nographic -cpu cortex-a57 \
+                        -pflash secure-world.rom \
+                        -pflash unsecure-world.rom
+
+Note that for some odd reason qemu-system-aarch64 needs to be explicitly
+told to use a 64-bit CPU or it will boot in 32-bit mode. The -nographic argument
+ensures that output appears on the terminal. Use Ctrl-A X to quit.
+
+Booting distros
+---------------
+
+It is possible to install and boot a standard Linux distribution using
+sbsa by setting up a root disk::
+
+.. code-block:: bash
+
+    qemu-img create root.img 20G
+
+then using the installer to install. For example, with Debian 12::
+
+.. code-block:: bash
+
+    qemu-system-aarch64 \
+      -machine sbsa-ref -cpu cortex-a57 -m 4G -smp 4 \
+      -pflash secure-world.rom \
+      -pflash unsecure-world.rom \
+      -device virtio-rng-pci \
+      -device usb-kbd -device usb-tablet \
+      -cdrom debian-12.0.0-arm64-netinst.iso \
+      -hda root.img
+
+Debug UART
+----------
+
+The debug UART on the ARM sbsa board uses these settings::
+
+    CONFIG_DEBUG_UART=y
diff --git a/doc/develop/driver-model/virtio.rst b/doc/develop/driver-model/virtio.rst
index 8ac9c94cafe..31b94d04675 100644
--- a/doc/develop/driver-model/virtio.rst
+++ b/doc/develop/driver-model/virtio.rst
@@ -34,6 +34,7 @@ The following QEMU targets are supported.
 
   - qemu_arm_defconfig
   - qemu_arm64_defconfig
+  - qemu-arm-sbsa_defconfig
   - qemu-riscv32_defconfig
   - qemu-riscv64_defconfig
   - qemu-x86_defconfig