# Armv8-R AArch64 AEM FVP Support in meta-arm-bsp

## Overview
Fixed Virtual Platforms (FVP) are complete simulations of an Arm system,
including processor, memory and peripherals. These are set out in a
"programmer's view", which gives you a comprehensive model on which to build
and test your software.

The Armv8-R AEM FVP is a free of charge Armv8-R Fixed Virtual Platform. It
supports the latest Armv8-R feature set.

This BSP implements a reference stack for the AArch64 support in the R-class
first announced with the Cortex-R82 processor:
https://developer.arm.com/ip-products/processors/cortex-r/cortex-r82

Fast Models Fixed Virtual Platforms (FVP) Reference Guide:
https://developer.arm.com/docs/100966/latest

## BSP Support
The fvp-baser-aemv8r64 Yocto MACHINE supports the following BSP components:

 - boot-wrapper-aarch64
 - Kernel: linux-yocto-5.10

## Quick start: Howto Build and Run

### Host environment setup
Install the Required Packages for the Build Host:
https://www.yoctoproject.org/docs/latest/mega-manual/mega-manual.html#required-packages-for-the-build-host

Install the kas setup tool for bitbake based projects:
https://kas.readthedocs.io/en/latest/userguide.html#dependencies-installation

### Fetch sources
Fetch meta-arm repository:
```
mkdir -p ~/fvp-baser-aemv8r64-bsp
cd ~/fvp-baser-aemv8r64-bsp
git clone https://git.yoctoproject.org/git/meta-arm
```

### Build
```
cd ~/fvp-baser-aemv8r64-bsp
kas build meta-arm/kas/fvp-baser-aemv8r64-bsp.yml
```

### Run
To Run the Fixed Virtual Platform simulation tool you must download "Armv8-R
AEM FVP" from Arm developer (This might require the user to register) from this
address:
https://developer.arm.com/tools-and-software/simulation-models/fixed-virtual-platforms/arm-ecosystem-models
and install it on your host PC.

To run an image after the build is done:
```
export YOCTO_DEPLOY_IMGS_DIR="~/fvp-baser-aemv8r64-bsp/build/tmp/deploy/images/fvp-baser-aemv8r64/"
cd <path-to-AEMv8R_base_pkg>/models/Linux64_GCC-6.4/
./FVP_BaseR_AEMv8R \
-C bp.dram_metadata.init_value=0 \
-C bp.dram_metadata.is_enabled=true \
-C bp.dram_size=8 \
-C bp.exclusive_monitor.monitor_access_level=1 \
-C bp.pl011_uart0.unbuffered_output=1 \
-C bp.pl011_uart0.untimed_fifos=true \
-C bp.refcounter.non_arch_start_at_default=1 \
-C bp.smsc_91c111.enabled=0 \
-C bp.ve_sysregs.mmbSiteDefault=0 \
-C cache_state_modelled=true \
-C cluster0.gicv3.cpuintf-mmap-access-level=2 \
-C cluster0.gicv3.SRE-enable-action-on-mmap=2 \
-C cluster0.gicv3.SRE-EL2-enable-RAO=1 \
-C cluster0.gicv3.extended-interrupt-range-support=1 \
-C cluster0.has_aarch64=1 \
-C cluster0.NUM_CORES=4 \
-C cluster0.stage12_tlb_size=512 \
-C gic_distributor.GICD_CTLR-DS-1-means-secure-only=1 \
-C gic_distributor.GITS_BASER0-type=1 \
-C gic_distributor.ITS-count=1 \
-C gic_distributor.ITS-hardware-collection-count=1 \
-C gic_distributor.direct-lpi-support=1 \
-C gic_distributor.has-two-security-states=0 \
-C pctl.startup=0.0.0.* \
-C bp.virtio_net.enabled=1 \
-C cache_state_modelled=0 \
-C bp.vis.rate_limit-enable=0 \
-C bp.virtio_net.hostbridge.interfaceName=tap0 \
-a cluster0*=${YOCTO_DEPLOY_IMGS_DIR}/linux-system.axf \
-C bp.virtioblockdevice.image_path=${YOCTO_DEPLOY_IMGS_DIR}/core-image-minimal-fvp-baser-aemv8r64.wic
```

The terminal console login is `root` without password.

## Devices supported in the kernel
- serial
- virtio disk
- virtio network
- watchdog
- rtc

## Devices not supported or not functional
- Only one CPU since SMP is not functional in boot-wrapper-aarch64 yet

## Networking

To enable networking on the FVP via a host network interface, set up tap0 using
the following commands (Ubuntu 18.04 Host):
```
sudo apt-get install libvirt-bin
sudo virsh net-start default
sudo ip tuntap add dev tap0 mode tap user $(whoami)
sudo ifconfig tap0 0.0.0.0 promisc up
sudo brctl addif virbr0 tap0
```

To clean up the tap0 interface on the host use the following commands:
```
sudo brctl delif virbr0 tap0
sudo ip link set virbr0 down
sudo brctl delbr virbr0
sudo virsh net-destroy default
sudo ip link delete tap0
```