#!/usr/bin/env bash

# Special thanks to:
# https://github.com/Leoyzen/KVM-Opencore
# https://github.com/thenickdude/KVM-Opencore/
# https://github.com/qemu/qemu/blob/master/docs/usb2.txt
#
# qemu-img create -f qcow2 windows_hdd.img 512G
#
# echo 1 > /sys/module/kvm/parameters/ignore_msrs (this is required)
#
# wget https://fedorapeople.org/groups/virt/virtio-win/direct-downloads/archive-virtio/virtio-win-0.1.208-1/virtio-win-0.1.208.iso
#
# GPU passthrough is terrible with AMD cards which suffer from the "AMD reset
# bug". NVIDIA cards work very well with Windows VMs.

############################################################################
# NOTE: Tweak the "MY_OPTIONS" line in case you are having booting problems!
############################################################################

MY_OPTIONS="+ssse3,+sse4.2,+popcnt,+avx,+aes,+xsave,+xsaveopt,check"

# This script works for Big Sur, Catalina, Mojave, and High Sierra. Tested with
# macOS 10.15.6, macOS 10.14.6, and macOS 10.13.6

ALLOCATED_RAM="3072" # MiB
CPU_SOCKETS="1"
CPU_CORES="2"
CPU_THREADS="2"

REPO_PATH="."
OVMF_DIR="."

# Note: This script assumes that you are doing CPU + GPU passthrough. This
# script will need to be modified for your specific needs!
#
# We recommend doing the initial macOS installation without using passthrough
# stuff. In other words, don't use this script for the initial macOS
# installation.

# shellcheck disable=SC2054
args=(
  -enable-kvm -m "$ALLOCATED_RAM" -cpu host,kvm=on,+invtsc,vmware-cpuid-freq=on,"$MY_OPTIONS"
  -machine q35
  -usb -device usb-kbd -device usb-tablet
  -smp "$CPU_THREADS",cores="$CPU_CORES",sockets="$CPU_SOCKETS"
  -device usb-ehci,id=ehci
  -vga none
  # 01:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/570X/580/580X/590] [1002:67df] (rev ef)
  #         Subsystem: Sapphire Technology Limited Nitro+ Radeon RX 570/580/590 [1da2:e366]
  # 01:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere HDMI Audio [Radeon RX 470/480 / 570/580/590] [1002:aaf0]
  #         Subsystem: Sapphire Technology Limited Ellesmere HDMI Audio [Radeon RX 470/480 / 570/580/590] [1da2:aaf0]
  -device vfio-pci,host=01:00.0,multifunction=on
  # -device vfio-pci,host=01:00.0,multifunction=on,romfile=gpu_original_bios.bin
  -device vfio-pci,host=01:00.1
  # ASMedia ASM1142 USB 3.1 Host Controller (comment out as needed)
  # 03:00.0 USB controller [0c03]: ASMedia Technology Inc. ASM1142 USB 3.1 Host Controller [1b21:1242]
  -device vfio-pci,host=03:00.0,bus=pcie.0
  -drive if=pflash,format=raw,readonly,file="$REPO_PATH/$OVMF_DIR/OVMF_CODE.fd"
  -drive if=pflash,format=raw,file="$REPO_PATH/$OVMF_DIR/OVMF_VARS-1024x768.fd"
  -drive file="$REPO_PATH/windows.iso",media=cdrom  # Win10_21H2_English_x64.iso from Microsoft works great
  -drive file="$REPO_PATH/virtio-win-0.1.208.iso",media=cdrom
  -drive if=virtio,index=0,file="$REPO_PATH/windows_hdd.img",format=qcow2
  # -netdev tap,id=net0,ifname=tap0,script=no,downscript=no -device e1000e,netdev=net0,id=net0,mac=52:54:00:c9:18:27
  -netdev user,id=net0 -device e1000e,netdev=net0,id=net0,mac=52:54:00:c9:18:27
  -monitor stdio
  -display none
)

qemu-system-x86_64 "${args[@]}"