[U-Boot] [PATCH 0/6] ARMv7: Add HYP mode switching support

Christoffer Dall christoffer.dall at linaro.org
Fri May 31 08:11:15 CEST 2013


On Mon, May 06, 2013 at 03:17:44PM +0200, Andre Przywara wrote:
> (for GIT URL and Changelog see below)
>
> ARM CPUs with the virtualization extension have a new mode called
> HYP mode, which allows hypervisors to safely control and monitor
> guests. The current hypervisor (KVM and Xen) implementations
> require the kernel to be entered in that HYP mode.
>
> This patch series introduces a configuration variable
> CONFIG_ARMV7_VIRT which enables code to switch all cores into HYP
> mode. This is done automatically during execution of the bootm
> command (but could also be done earlier - U-Boot runs fine in HYP
> mode without MMU usage).

I forget the u-boot specifics here, but if you boot over networking, for
example, does that eventually end up calling bootm or would Hyp mode not
be entered in this case?

I'm only raising this issue because it's important to minimize the hoops
and efforts for booting in Hyp mode, since it's harmless to do so
regardless of the linux kernel we're booting.

[...]

-Christoffer


More information about the U-Boot mailing list