All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Jan Beulich" <JBeulich@suse.com>
To: Stefano Stabellini <stefano.stabellini@eu.citrix.com>,
	Shannon Zhao <zhaoshenglong@huawei.com>
Cc: xen-devel@lists.xensource.com,
	IanCampbell <Ian.Campbell@citrix.com>,
	Christoffer Dall <christoffer.dall@linaro.org>,
	Shannon Zhao <shannon.zhao@linaro.org>
Subject: Re: Runtime services support for Xen on ARM
Date: Tue, 10 Nov 2015 06:12:39 -0700	[thread overview]
Message-ID: <5641FB5702000078000B361F@prv-mh.provo.novell.com> (raw)
In-Reply-To: <alpine.DEB.2.02.1511101210580.5676@kaball.uk.xensource.com>

>>> On 10.11.15 at 13:26, <stefano.stabellini@eu.citrix.com> wrote:
> CC'ing xen-devel and Jan
> 
> On Tue, 10 Nov 2015, Shannon Zhao wrote:
>> Hi Stefano,
>> 
>> I'm working on adding Runtime services support at Xen side. Most of work
>> is adding the ARM part in xen/common/efi/runtime.c.
>> 
>> There is one problem which block me. That is how to implement
>> efi_rs_enter() and efi_rs_leave() for ARM, since I think current
>> implementation is x86 specific and won't work on ARM. Also the rtc_lock.
>> 
>> Could you give some suggestion? Thanks!
> 
> efi_rs_enter() and efi_rs_leave() look very PV x86 specific. It is
> possible that we don't actually need to do anything at all on ARM, aside
> from refactoring the code. Jan?

Whether you need to do much on ARM I don't know; doing
nothing doesn't seem to be among the options though, as at the
very least you need to acquire/release efi_rs_lock. The fact that
the code will need refactoring has been well known since the time
it got made common.

> Similarly we don't have an rtc_lock spinlock today and it is not
> actually needed, but for the sake of keeping the common code common, I
> would just introduce rtc_lock on ARM too.

I think this would better be hidden behind an arch abstraction,
doing nothing on ARM.

Jan

      parent reply	other threads:[~2015-11-10 13:12 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <5641D5F0.5080401@huawei.com>
2015-11-10 12:26 ` Runtime services support for Xen on ARM Stefano Stabellini
2015-11-10 12:36   ` Ian Campbell
2015-11-10 14:27     ` Shannon Zhao
2015-11-12  9:06     ` Shannon Zhao
2015-11-12 11:04       ` Jan Beulich
2015-11-12 12:52         ` Shannon Zhao
2015-11-12 15:29           ` Jan Beulich
2015-11-10 13:12   ` Jan Beulich [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=5641FB5702000078000B361F@prv-mh.provo.novell.com \
    --to=jbeulich@suse.com \
    --cc=Ian.Campbell@citrix.com \
    --cc=christoffer.dall@linaro.org \
    --cc=shannon.zhao@linaro.org \
    --cc=stefano.stabellini@eu.citrix.com \
    --cc=xen-devel@lists.xensource.com \
    --cc=zhaoshenglong@huawei.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.