[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v4 1/7] docs/arm: Document Xen booting protocol on Armv8-R
- To: "Orzel, Michal" <Michal.Orzel@xxxxxxx>
- From: Luca Fancellu <Luca.Fancellu@xxxxxxx>
- Date: Wed, 30 Apr 2025 06:58:33 +0000
- Accept-language: en-GB, en-US
- Arc-authentication-results: i=2; mx.microsoft.com 1; spf=pass (sender ip is 4.158.2.129) smtp.rcpttodomain=amd.com smtp.mailfrom=arm.com; dmarc=pass (p=none sp=none pct=100) action=none header.from=arm.com; dkim=pass (signature was verified) header.d=arm.com; arc=pass (0 oda=1 ltdi=1 spf=[1,1,smtp.mailfrom=arm.com] dkim=[1,1,header.d=arm.com] dmarc=[1,1,header.from=arm.com])
- Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=arm.com; dmarc=pass action=none header.from=arm.com; dkim=pass header.d=arm.com; arc=none
- Arc-message-signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=ef58SYXk03KkxovSI4AdUOji2JJ1aaqFvyDT547p82o=; b=ntwHB9m1o9ToGmPwwLmlhMROaXscIYfQ3VfJ7MG2rWW3E+9OIdADX59bJ1imaMTfIiEAWv2nHdsDmIfXxIVyaJbBqjOviCs6Oy0N+bG23eZySt/SSjGT++km3CswVINAw1escqww7zWd90ANxQWbrZ9DwNEs7zEFT9MW5pCUbZaToXG8xNzH598rbbWXlPq9UpN3Jr6hd1WRfwYw5K8bk+U4royzhvgI006K4w1h9fLj/J24YEtGr2gKT2DkZ2LtWS/eDRBtPfODdFhzPe28ukf7oizaPDhCn/S9hoiHytO0Hj+u+okpOlQXFIMwe3PcWdSoW3uT6Nzg1A+URBrvVA==
- Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=ef58SYXk03KkxovSI4AdUOji2JJ1aaqFvyDT547p82o=; b=en2MCulMHxrg54TNLd+WZHbYw0mEYWbj/WvbEjagDEThPDpYx27N0fPSBpF3/ss+Ba8KXTfRbOWj5vRSMDgY9ZalBwijBAusQ03rW99gRxNgiY+5uWJSYuCaig/7sLZocVEYwZC0ETrKMjk88ScBLXHOCTrk5IhHO9P9kC5jlji608avJ4nQTWEA7YUyPau2gczbXKjikyCjfW/iVnmeapC46nHEjF7g/9PGpoQQ31xHwsmIOkBsgvJJoRZWB9baTERDqOxihe0Jbn9g4ZvDNoBs7YQQlgCpTCDTN0d1jN9bJt+KxYal3n7dhInJv4bU5B7QlhjMG3bRjORWfKNNzg==
- Arc-seal: i=2; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=pass; b=mDHXtxvn4D2lGEfwL/1Zs7lVLWqb0OwBESBHfTyEQWRPpKV8aJ6Prpgs8TYyqs7VP4322ffRIAtY7QYCaTdq/8n2AKl0LljQ6Wb9J7QpctAwhsNSRbJauodR8njOqCjFn6QFWAl7OrHkrlS7kqPzVtA9eISdOm/0RuZaXlYiguz0coEqbSBbfAzaqUQ3N9PiG3cIRmJYSBeTww3PZ6XARQ7CaTUyvGum4f0BhMO52T8sXoBlJ5waiY/XEJC7gxFsXudAfnE3pAcC8sR2m1e7Rdznw6SgrvmvFPloTxNP5p3TXnxi+eu5PLoXUSvu/kgJ8Vg0NtES7H7gffIDTeEGSw==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=vBQPIK9q6WSbGKCJKLY7TAIqUAudJGBBI61s21f1kw+rZhfXh0Lnym8gRjYvZY/+nidQ3Xelesmfaw44KnllzFHg6cinj0HpShvOIOfxprA9qK7LOve9f3BQM82OMvov+9yM12QHMZJetuFMSc4NwKNe1AtP6CzQ+zDJTgkX5lXlHXbQbwMQMzEMWaYGuI1zwJ0kM8TzE+yQJEPvKTCoRKUZJesDJ1WmUrblS09rQbccMFX4owxJsPpEj8mlfHGOyQ/PBl0rj79eSqysqmHCZTkWjeaRTmBOzr0e5P9y28NnwYdkz6Y0LUawCjHjtXBu6lAXQWmk/PvAlYMBCsU85g==
- Authentication-results-original: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=arm.com;
- Cc: "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>, Stefano Stabellini <sstabellini@xxxxxxxxxx>, Julien Grall <julien@xxxxxxx>, Bertrand Marquis <Bertrand.Marquis@xxxxxxx>, Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>
- Delivery-date: Wed, 30 Apr 2025 06:59:15 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
- Nodisclaimer: true
- Thread-index: AQHbuRpmN9lJogKQoUiVWa6WakCsQrO7wm+AgAAFy4A=
- Thread-topic: [PATCH v4 1/7] docs/arm: Document Xen booting protocol on Armv8-R
Hi Michal,
> On 30 Apr 2025, at 07:37, Orzel, Michal <Michal.Orzel@xxxxxxx> wrote:
>
>
>
> On 29/04/2025 17:20, Luca Fancellu wrote:
>> Document the requirement needed to boot Xen on Armv8-R platforms.
>>
>> Signed-off-by: Luca Fancellu <luca.fancellu@xxxxxxx>
>> ---
>> v4 changes:
>> - New patch
>> ---
>> docs/misc/arm/booting.txt | 8 ++++++++
>> 1 file changed, 8 insertions(+)
>>
>> diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt
>> index 21ae74837dcc..719af74f1e69 100644
>> --- a/docs/misc/arm/booting.txt
>> +++ b/docs/misc/arm/booting.txt
>> @@ -62,6 +62,14 @@ Xen relies on some settings the firmware has to configure
>> in EL3 before starting
>>
>> * The bit SCR_EL3.HCE (resp. SCR.HCE for 32-bit ARM) must be set to 1.
>>
>> +When Xen runs on Armv8-R, the highest exception level is EL2 and the only
>> +available state is secure (S) on Arm64 and non secure (NS) on Arm32, hence
>> the
>> +above requirements need to be adjusted to this case:
>> +
>> +* Xen must be entered in S EL2 mode on Arm64 and in NS EL2 mode on Arm32.
>> +
>> +* Xen must be entered with MPU off and data cache disabled (SCTLR_EL2.M bit
>> and
>> + SCTLR_EL2.C set to 0).
>>
>> [1] linux/Documentation/arm/booting.rst
>> Latest version:
>> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/arch/arm/booting.rst
>
> Is the goal of this patch to only write firmware/bootloader requirements or
> accommodate booting protocol in general? Asking because in this file there is
> a
> requirement that Xen should be loaded below 10TB which afaict does not fit
> Armv8-R.
Yes you are right, but I think this still holds since we support 1TB on Armv8-R
at the moment?
Cheers,
Luca
|
