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Daniel Golle
ce7bee88da
Legacy fbdev carries the boot framebuffer on armsr today, through efifb and the PL111 driver, and armv8 guests on Hyper-V go through hyperv_fb. A DRM driver can claim the firmware framebuffer on its own, so those hardware drivers only add size to every image. Mark the firmware framebuffer as a generic system framebuffer so sysfb registers it as simple-framebuffer, and let simpledrm bind to it. sysfb builds that device from the screen_info the EFI stub hands over, so SystemReady hardware and EDK2 or U-Boot virtual platforms keep their display. DRM fbdev emulation and fbcon stay, so the boot log and the console prompt still reach the screen; the emulation serves fbcon, as generic leaves FB_DEVICE off and no /dev/fb node appears. armv8 gains hyperv_drm as its Hyper-V driver's help text asks, and loses the backlight class and the videomode helpers, which a machine with no panel has no use for. DRM_BOCHS, DRM_QXL and DRM_VIRTIO_GPU are untouched. Signed-off-by: Daniel Golle <daniel@makrotopia.org>
This target generates images that can be used on ARM machines with EFI
support (e.g EDKII/TianoCore or U-Boot with bootefi).
There are two subtargets:
- armv7 for 32-bit machines
- armv8 for 64-bit machines
The kernel and filesystem images can also be used directly by QEMU:
Run with qemu-system-arm
# boot with initramfs embedded in
qemu-system-arm -nographic -M virt -m 64 -kernel openwrt-armsr-armv7-generic-initramfs-kernel.bin
# boot with accel=kvm
qemu-system-arm -nographic -M virt,accel=kvm -cpu host -m 64 -kernel
openwrt-armsr-armv7-generic-initramfs-kernel.bin
# boot with a separate rootfs
qemu-system-arm -nographic -M virt -m 64 -kernel openwrt-armsr-armv7-generic-kernel.bin \
-drive file=openwrt-armsr-armv7-generic-ext4-rootfs.img,format=raw,if=virtio -append 'root=/dev/vda rootwait'
# boot with local dir as rootfs
qemu-system-arm -nographic -M virt -m 64 -kernel openwrt-armsr-armv7-generic-kernel.bin \
-fsdev local,id=rootdev,path=root-armsr/,security_model=none \
-device virtio-9p-pci,fsdev=rootdev,mount_tag=/dev/root \
-append 'rootflags=trans=virtio,version=9p2000.L,cache=loose rootfstype=9p'
Run with kvmtool
# start a named machine
lkvm run -k openwrt-armsr-armv7-zImage -i openwrt-armsr-armv7-rootfs.cpio --name armsr0
# start with virtio-9p rootfs
lkvm run -k openwrt-armsr-armv7-zImage -d root-armsr/
# stop "armsr0"
lkvm stop --name armsr0
# stop all
lkvm stop --all
The multi-platform ARMv8 target can be used with QEMU:
qemu-system-aarch64 -machine virt -cpu cortex-a57 -nographic \
-kernel openwrt-armsr-armv8-generic-initramfs-kernel.bin \
With a EDKII or U-Boot binary for the QEMU ARM virtual machines, you can use these
images in EFI mode:
32-bit:
gunzip -c bin/targets/armsr/armv7/openwrt-armsr-armv7-generic-ext4-combined-efi.img.gz > openwrt-arm-32.img
qemu-system-arm -nographic \
-cpu cortex-a15 -machine virt \
-bios bin/targets/armsr/armv7/u-boot-qemu_armv7/u-boot.bin \
-smp 1 -m 1024 \
-device virtio-rng-pci \
-drive file=openwrt-arm-32.img,format=raw,index=0,media=disk \
-netdev user,id=testlan -net nic,netdev=testlan \
-netdev user,id=testwan -net nic,netdev=testwan
64-bit:
gunzip -c bin/targets/armsr/armv8/openwrt-armsr-armv8-generic-ext4-combined-efi.img.gz > openwrt-arm-64.img
qemu-system-aarch64 -nographic \
-cpu cortex-a53 -machine virt \
-bios bin/targets/armsr/armv8/u-boot-qemu_armv8/u-boot.bin \
-smp 1 -m 1024 \
-device virtio-rng-pci \
-drive file=openwrt-arm-64.img,format=raw,index=0,media=disk \
-netdev user,id=testlan -net nic,netdev=testlan \
-netdev user,id=testwan -net nic,netdev=testwan
One can obtain other EFI/BIOS binaries from:
- Distribution packages (such as qemu-efi-arm and qemu-efi-aarch64 in Debian)
- Community builds, like retrage/edk2-nightly: https://retrage.github.io/edk2-nightly/