public inbox for linux-arm-kernel@lists.infradead.org 
 help / color / mirror / Atom feed
From: will.deacon@arm•com (Will Deacon)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH] iommu/arm-smmu-v2: Add support for 16 bit VMID
Date: Fri, 19 Feb 2016 17:13:30 +0000	[thread overview]
Message-ID: <20160219171329.GO27062@arm.com> (raw)
In-Reply-To: <1455819817-8432-1-git-send-email-tchalamarla@caviumnetworks.com>

On Thu, Feb 18, 2016 at 10:23:37AM -0800, tchalamarla at caviumnetworks.com wrote:
> From: Tirumalesh Chalamarla <tchalamarla@caviumnetworks•com>
> 
> ARM-SMMUv2 supports upto 16 bit VMID. This patch enables
> 16 bit VMID when requested from device-tree.
> 
> Signed-off-by: Tirumalesh Chalamarla <tchalamarla@caviumnetworks•com>
> ---
>  .../devicetree/bindings/iommu/arm,smmu.txt          |  2 ++
>  drivers/iommu/arm-smmu.c                            | 21 ++++++++++++++++++++-
>  2 files changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
> index 7180745..bb7e569 100644
> --- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt
> +++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
> @@ -55,6 +55,8 @@ conditions.
>                    aliases of secure registers have to be used during
>                    SMMU configuration.
>  
> +- smmu-enable-vmid16 : Enable 16 bit VMID, if allowed.

Why do we need a new property for this, given that we can detect it
from the ID registers? I can't think of a reason why we wouldn't use
16-bit VMIDs if they were available to us.

Will

  reply	other threads:[~2016-02-19 17:13 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-18 18:23 [PATCH] iommu/arm-smmu-v2: Add support for 16 bit VMID tchalamarla at caviumnetworks.com
2016-02-19 17:13 ` Will Deacon [this message]
2016-02-19 18:36   ` Tirumalesh Chalamarla

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=20160219171329.GO27062@arm.com \
    --to=will.deacon@arm$(echo .)com \
    --cc=linux-arm-kernel@lists$(echo .)infradead.org \
    /path/to/YOUR_REPLY

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