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Date: Wed, 7 Aug 2019 18:09:57 +0200
From: =?UTF-8?B?Um9nZXIgUGF1IE1vbm7DqQ==?= <roger.pau@citrix.com>
To: <devel@edk2.groups.io>, <anthony.perard@citrix.com>
CC: Julien Grall <julien.grall@arm.com>, <xen-devel@lists.xenproject.org>,
	Jordan Justen <jordan.l.justen@intel.com>, Ard Biesheuvel
	<ard.biesheuvel@linaro.org>, Laszlo Ersek <lersek@redhat.com>
Subject: Re: [edk2-devel] [PATCH v4 35/35] OvmfPkg/OvmfXen: use RealTimeClockRuntimeDxe from EmbeddedPkg
Message-ID: <20190807160957.csgyplb6cqfen5ix@Air-de-Roger>
References: <20190729153944.24239-1-anthony.perard@citrix.com>
 <20190729153944.24239-36-anthony.perard@citrix.com>
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On Mon, Jul 29, 2019 at 04:39:44PM +0100, Anthony PERARD wrote:
> A Xen PVH guest doesn't have a RTC that OVMF would expect, so
> PcatRealTimeClockRuntimeDxe fails to initialize and prevent the
> firmware from finish to boot. To prevent that, we will use
> XenRealTimeClockLib which simply always return the same time.
> This will work on both Xen PVH and HVM guests.

Not that this is not correct, but what's the point in requiring a
clock if it can be faked by always returning the same value?

It seems like it's usage is not really required, and could indeed be
dropped altogether?

Alternatively, there's the PV clock which is available to PVH guests
and will return a proper time.

Thanks, Roger.