From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [PATCH FOR-4.5] xen: arm: Do not enable EFI in dom0 since it is not yet supported. Date: Tue, 14 Oct 2014 14:47:48 +0100 Message-ID: <1413294468.10417.58.camel@citrix.com> References: <1413217030-9170-1-git-send-email-suravee.suthikulpanit@amd.com> <543BFBCF.8010008@linaro.org> <1413271285.1497.3.camel@citrix.com> <543D16E6.7020209@linaro.org> <1413290968.10417.44.camel@citrix.com> <543D1DFC.8020901@linaro.org> <1413292069.10417.55.camel@citrix.com> <543D22B5.5080502@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <543D22B5.5080502@linaro.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Julien Grall Cc: Vijay Kilari , Vijaya Kumar K , Stefano Stabellini , xen-devel , Roy Franz , Suravee Suthikulpanit List-Id: xen-devel@lists.xenproject.org On Tue, 2014-10-14 at 14:18 +0100, Julien Grall wrote: > On 10/14/2014 02:07 PM, Ian Campbell wrote: > > On Tue, 2014-10-14 at 13:58 +0100, Julien Grall wrote: > >> On 10/14/2014 01:49 PM, Ian Campbell wrote: > >>> On Tue, 2014-10-14 at 13:28 +0100, Julien Grall wrote: > >>>> Hi Ian, > >>>> > >>>> On 10/14/2014 08:21 AM, Ian Campbell wrote: > >>>>> On Mon, 2014-10-13 at 12:37 -0700, Roy Franz wrote: > >>>>>> On Mon, Oct 13, 2014 at 9:20 AM, Julien Grall wrote: > >>>>>>> (CC vijay) > >>>>>>> > >>>>>>> Hi Suravee, > >>>>>>> > >>>>>>> On 10/13/2014 05:17 PM, suravee.suthikulpanit@amd.com wrote: > >>>>>>>> From: Suravee Suthikulpanit > >>>>>>>> > >>>>>>>> Since EFI is not yet supported in dom0, we need to remove the following > >>>>>>>> properties from the chosen node: > >>>>>>>> > >>>>>>>> * linux,uefi-mmap-start > >>>>>>>> * linux,uefi-mmap-size > >>>>>>>> * linux,uefi-mmap-desc-size > >>>>>>>> * linux,uefi-mmap-desc-ver > >>>>>>>> > >>>>>>>> These are added by "arch/arm/efi/efi-boot.h: fdt_add_uefi_nodes()", > >>>>>>>> and used by dom0 kernel to enable EFI. > >>>>>>>> > >>>>>>>> Cc: Julien Grall > >>>>>>>> Cc: Stefano Stabellini > >>>>>>>> Cc: Ian Campbell > >>>>>>>> Cc: Roy Franz > >>>>>>>> Signed-off-by: Suravee Suthikulpanit > >>>>>>> > >>>>>>> Reviewed-by: Julien Grall > >>>>>> > >>>>>> Reviewed-by: Roy Franz > >>>>> > >>>>> Acked-by: Ian Campbell > >>>>> > >>>>> But I do wonder why we don't just drop the hos /chosen node -- I think > >>>>> everything which should be in there is fabricated by the h/visor anyway. > >>>> > >>>> I though about the same things yesterday, but the /chosen node may > >>>> contain other properties (such as OS specific) that we may need to pass > >>>> to DOM0. > >>> > >>> What sort of thing are you thinking of here? > >> > >> FreeBSD provides two properties (stdin and stdout) to choose the input > >> and the output methods. > >> > >> Those properties need to be copied in DOM0 DT to allow the user chose > >> which console he wants to use (think about a platform with 2 serial ports). > > > > How do you know whether stdin/stdout were intended to apply to dom0 or > > Xen? > > We specify the console for Xen via the Xen command line. > > > What if dom0 wants to use hvc0? How is that expressed? > > For now it has the priority against anything else. But in ideal world, > the HVC console should be describe in a device node add by Xen. > > > It seems to me that if bootargs is being consumed by Xen then > > stdin/stdout ought to be consumed by Xen for consistency. > > stdin/stdout is part of FreeBSD command line. If we use those > properties, why don't we parse Linux command line to get the console? > OK. I'm confused. I was talking about device-tree properties under /chosen so I thought you were saying that stdin/stdout were such things. If they are part of the bsd command line (i.e. part of xen,dom0-bootargs or similar) then there is no problem -- we pass them through just like we do today. > > Which points to special handling for stdin/stdout in Xen, i.e. a > > continuation of the whitelisting approach. > > And how do you chose the console for DOM0? For Linux we have to use > console=hvc0 on the command line. FreeBSD choose to use stdin/stdout. Are you now saying that they aren't in the FreeBSD command line but are properties? If you are saying that they are dt properties then stdin/stdout should be handled just like bootargs IMHO, not simply happen to work due to a partial blacklist Ian.