linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Zenghui Yu <yuzenghui@huawei.com>
To: Marc Zyngier <maz@kernel.org>
Cc: <linux-arm-kernel@lists.infradead.org>,
	<kvmarm@lists.cs.columbia.edu>, <kvm@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>,
	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
	Jason Cooper <jason@lakedaemon.net>,
	"Robert Richter" <rrichter@marvell.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Eric Auger" <eric.auger@redhat.com>,
	James Morse <james.morse@arm.com>,
	"Julien Thierry" <julien.thierry.kdev@gmail.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>
Subject: Re: [PATCH v5 01/23] irqchip/gic-v3: Use SGIs without active state if offered
Date: Fri, 13 Mar 2020 09:39:08 +0800	[thread overview]
Message-ID: <3e20f3c3-0312-bd29-dcfc-2afee764ef19@huawei.com> (raw)
In-Reply-To: <1bff1835ba7d6e22edb836d38cf16a14@kernel.org>

Hi Marc,

On 2020/3/12 20:05, Marc Zyngier wrote:
> On 2020-03-12 09:28, Marc Zyngier wrote:
>> Hi Zenghui,
>>
>> On 2020-03-12 06:30, Zenghui Yu wrote:
>>> Hi Marc,
>>>
>>> On 2020/3/5 4:33, Marc Zyngier wrote:
>>>> To allow the direct injection of SGIs into a guest, the GICv4.1
>>>> architecture has to sacrifice the Active state so that SGIs look
>>>> a lot like LPIs (they are injected by the same mechanism).
>>>>
>>>> In order not to break existing software, the architecture gives
>>>> offers guests OSs the choice: SGIs with or without an active
>>>> state. It is the hypervisors duty to honor the guest's choice.
>>>>
>>>> For this, the architecture offers a discovery bit indicating whether
>>>> the GIC supports GICv4.1 SGIs (GICD_TYPER2.nASSGIcap), and another
>>>> bit indicating whether the guest wants Active-less SGIs or not
>>>> (controlled by GICD_CTLR.nASSGIreq).
>>>
>>> I still can't find the description of these two bits in IHI0069F.
>>> Are they actually architected and will be available in the future
>>> version of the spec?  I want to confirm it again since this has a
>>> great impact on the KVM code, any pointers?
>>
>> Damn. The bits *are* in the engineering spec version 19 (unfortunately
>> not a public document, but I believe you should have access to it).
>>
>> If the bits have effectively been removed from the spec, I'll drop the
>> GICv4.1 code from the 5.7 queue until we find a way to achieve the same
>> level of support.
>>
>> I've emailed people inside ARM to find out.
> 
> I've now had written confirmation that the bits are still there.
> 
> It is just that the current revision of the documentation was cut *before*
> they made it into the architecture (there seem to be a 6 month delay 
> between
> the architecture being sampled and the documentation being released).

I see. Thanks for the confirmation!


Zenghui


  reply	other threads:[~2020-03-13  1:39 UTC|newest]

Thread overview: 114+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-04 20:33 [PATCH v5 00/23] irqchip/gic-v4: GICv4.1 architecture support Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 01/23] irqchip/gic-v3: Use SGIs without active state if offered Marc Zyngier
2020-03-12  6:30   ` Zenghui Yu
2020-03-12  9:28     ` Marc Zyngier
2020-03-12 12:05       ` Marc Zyngier
2020-03-13  1:39         ` Zenghui Yu [this message]
2020-03-12 17:16   ` Auger Eric
2020-03-12 17:23     ` Marc Zyngier
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 02/23] irqchip/gic-v4.1: Skip absent CPUs while iterating over redistributors Marc Zyngier
2020-03-16 17:10   ` Auger Eric
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 03/23] irqchip/gic-v4.1: Ensure mutual exclusion between vPE affinity change and RD access Marc Zyngier
2020-03-12  6:56   ` Zenghui Yu
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 04/23] irqchip/gic-v4.1: Wait for completion of redistributor's INVALL operation Marc Zyngier
2020-03-20 14:23   ` Auger Eric
2020-03-04 20:33 ` [PATCH v5 05/23] irqchip/gic-v4.1: Ensure mutual exclusion betwen invalidations on the same RD Marc Zyngier
2020-03-12  7:11   ` Zenghui Yu
2020-03-20 14:23   ` Auger Eric
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 06/23] irqchip/gic-v4.1: Advertise support v4.1 to KVM Marc Zyngier
2020-03-16 17:10   ` Auger Eric
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 07/23] irqchip/gic-v4.1: Map the ITS SGIR register page Marc Zyngier
2020-03-16 17:10   ` Auger Eric
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 08/23] irqchip/gic-v4.1: Plumb skeletal VSGI irqchip Marc Zyngier
2020-03-16 17:10   ` Auger Eric
2020-03-19 10:03     ` Marc Zyngier
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 09/23] irqchip/gic-v4.1: Add initial SGI configuration Marc Zyngier
2020-03-16 17:53   ` Auger Eric
2020-03-17  2:02     ` Zenghui Yu
2020-03-17  8:36       ` Auger Eric
2020-03-19 10:20     ` Marc Zyngier
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 10/23] irqchip/gic-v4.1: Plumb mask/unmask SGI callbacks Marc Zyngier
2020-03-16 18:15   ` Auger Eric
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 11/23] irqchip/gic-v4.1: Plumb get/set_irqchip_state " Marc Zyngier
2020-03-12  7:41   ` Zenghui Yu
2020-03-16 21:43   ` Auger Eric
2020-03-19 10:27     ` Marc Zyngier
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 12/23] irqchip/gic-v4.1: Plumb set_vcpu_affinity " Marc Zyngier
2020-03-17 10:35   ` Auger Eric
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 13/23] irqchip/gic-v4.1: Move doorbell management to the GICv4 abstraction layer Marc Zyngier
2020-03-12  8:20   ` Zenghui Yu
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 14/23] irqchip/gic-v4.1: Add VSGI allocation/teardown Marc Zyngier
2020-03-12  8:06   ` Zenghui Yu
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 15/23] irqchip/gic-v4.1: Add VSGI property setup Marc Zyngier
2020-03-12  8:09   ` Zenghui Yu
2020-03-17 10:30   ` Auger Eric
2020-03-19 10:57     ` Marc Zyngier
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 16/23] irqchip/gic-v4.1: Eagerly vmap vPEs Marc Zyngier
2020-03-12  8:12   ` Zenghui Yu
2020-03-17  2:49   ` Zenghui Yu
2020-03-19 10:55     ` Marc Zyngier
2020-03-20  2:31       ` Zenghui Yu
2020-03-29 20:26   ` [tip: irq/core] " tip-bot2 for Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 17/23] KVM: arm64: GICv4.1: Let doorbells be auto-enabled Marc Zyngier
2020-03-12  8:15   ` Zenghui Yu
2020-03-17 11:04   ` Auger Eric
2020-03-04 20:33 ` [PATCH v5 18/23] KVM: arm64: GICv4.1: Add direct injection capability to SGI registers Marc Zyngier
2020-03-18  3:28   ` Zenghui Yu
2020-03-20  8:11   ` Auger Eric
2020-03-20 10:05     ` Marc Zyngier
2020-03-20 10:56       ` Auger Eric
2020-03-04 20:33 ` [PATCH v5 19/23] KVM: arm64: GICv4.1: Allow SGIs to switch between HW and SW interrupts Marc Zyngier
2020-03-19 16:16   ` Auger Eric
2020-03-19 19:52     ` Marc Zyngier
2020-03-19 20:13       ` Auger Eric
2020-03-20  9:17         ` Marc Zyngier
2020-03-20  4:22   ` Zenghui Yu
2020-03-04 20:33 ` [PATCH v5 20/23] KVM: arm64: GICv4.1: Plumb SGI implementation selection in the distributor Marc Zyngier
2020-03-18  6:34   ` Zenghui Yu
2020-03-19 12:10     ` Marc Zyngier
2020-03-19 20:38       ` Auger Eric
2020-03-20  3:08         ` Zenghui Yu
2020-03-20  7:59           ` Auger Eric
2020-03-20  9:46             ` Marc Zyngier
2020-03-20 11:09               ` Auger Eric
2020-03-20 11:20                 ` Marc Zyngier
2020-03-20  3:53       ` Zenghui Yu
2020-03-20  9:01         ` Marc Zyngier
2020-03-23  8:11           ` Zenghui Yu
2020-03-23  8:25             ` Marc Zyngier
2020-03-23 12:40               ` Zenghui Yu
2020-03-04 20:33 ` [PATCH v5 21/23] KVM: arm64: GICv4.1: Reload VLPI configuration on distributor enable/disable Marc Zyngier
2020-03-18  3:17   ` Zenghui Yu
2020-03-19 12:18     ` Marc Zyngier
2020-03-04 20:33 ` [PATCH v5 22/23] KVM: arm64: GICv4.1: Allow non-trapping WFI when using HW SGIs Marc Zyngier
2020-03-20  4:23   ` Zenghui Yu
2020-03-20  8:12   ` Auger Eric
2020-03-04 20:33 ` [PATCH v5 23/23] KVM: arm64: GICv4.1: Expose HW-based SGIs in debugfs Marc Zyngier
2020-03-18  3:19   ` Zenghui Yu
2020-03-19 15:05   ` Auger Eric
2020-03-19 15:21     ` Marc Zyngier
2020-03-19 15:43       ` Auger Eric
2020-03-19 16:16         ` Marc Zyngier
2020-03-19 16:17           ` Auger Eric
2020-03-20  4:38       ` Zenghui Yu
2020-03-20  9:09         ` Marc Zyngier
2020-03-20 11:35           ` Zenghui Yu
2020-03-20 11:46             ` Marc Zyngier
2020-03-20 12:09               ` Zenghui Yu
2020-03-05  3:39 ` [PATCH v5 00/23] irqchip/gic-v4: GICv4.1 architecture support Zenghui Yu
2020-03-09  8:17 ` Zenghui Yu
2020-03-09  8:46   ` Marc Zyngier

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=3e20f3c3-0312-bd29-dcfc-2afee764ef19@huawei.com \
    --to=yuzenghui@huawei.com \
    --cc=eric.auger@redhat.com \
    --cc=james.morse@arm.com \
    --cc=jason@lakedaemon.net \
    --cc=julien.thierry.kdev@gmail.com \
    --cc=kvm@vger.kernel.org \
    --cc=kvmarm@lists.cs.columbia.edu \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lorenzo.pieralisi@arm.com \
    --cc=maz@kernel.org \
    --cc=rrichter@marvell.com \
    --cc=suzuki.poulose@arm.com \
    --cc=tglx@linutronix.de \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).