Hi Alexander > From: Alexander Spyridakis [mailto:a.spyrida...@virtualopensystems.com] > Sent: Monday, February 15, 2016 15:38 > To: Yehuda Yitschak > Cc: Peter Maydell; qemu-discuss@nongnu.org; > a.spyrida...@virtualopensystems.com; Jérémy Fanguède > Subject: Re: [Qemu-discuss] Booting GUI ubuntu VM on Aarch64 > > Hello, > > On 15 February 2016 at 12:55, Yehuda Yitschak <yehu...@marvell.com> wrote: > I just built qemu-2.5 so I can try the virtio-gpu-pci approach. > > Btw - I found a demo from virtual open system where they show guest graphics > on Exynos based Arndale board. > It doesn’t show how but maybe it gives a hint > http://www.virtualopensystems.com/en/solutions/demos/kvm-on-arndale-exynos/ > > > > Are you interested in graphics with TCG or KVM? With TCG the usual command > line should work out of the box with the default bochs vga device: "-device > VGA -device usb-ehci -device usb-tablet - device usb-kbd". Don't forget to > enable the bochs driver in your guest kernel, and depending on your distro > you might have to play around with the X configuration to get it right. > > With KVM as Peter mentioned, you need some additional patches for device > cache coherency. Have a look at two patches from Jeremy Fanguede: "[RFC 0/4] > arm/arm64: KVM: Get around cache incoherency" and "[RFC] ARM/ARM64: KVM: > Implement KVM_FLUSH_DCACHE_GPA ioctl". These patches are not meant only for > the VGA, but also emulated usb devices, without them your mouse and > > keyboard won't work.
I want to use KVM tough it looks like a not a trivial hack for the non QEMU expert like me :) Would you mind sharing how you achieved graphics in your demo above ? did you use TCG or did you also go through these workarounds ? Thanks a lot Yehuda > Additionally, with KVM you might need to brute-force the rendering of the VGA > device in QEMU by removing the check on memory_region_get_dirty(). This is a > very ugly hack but it should work (hw/display/vga.c in vga_draw_graphic), > which is similar to this: > https://github.com/virtualopensystems/qemu/commit/64dd1b3e3a2353433edb9c63d00271f515bd06fb Regards.