Subject: [PATCH RFC v2 3/3] documentation/iommu: Add description of Hisilicon SMMU private binding

From: [email-masked] (Will Deacon)
Date: Mon, 16 Jun 2014 17:39:30 +0100

On Thu, Jun 12, 2014 at 06:08:12AM +0100, Zhen Lei wrote:
> This patch adds a description of private properties for the Hisilicon
> System MMU architecture.
> 
> Signed-off-by: Zhen Lei <[email-masked]>
> ---
>  Documentation/devicetree/bindings/iommu/arm,smmu.txt | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
> index f284b99..75b1351 100644
> --- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt
> +++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
> @@ -15,6 +15,7 @@ conditions.
>                          "arm,smmu-v2"
>                          "arm,mmu-400"
>                          "arm,mmu-500"
> +                        "hisilicon,smmu-v1"
> 
>                    depending on the particular implementation and/or the
>                    version of the architecture implemented.
> @@ -54,6 +55,21 @@ conditions.
>                    aliases of secure registers have to be used during
>                    SMMU configuration.
> 
> +** Hisilicon SMMU private properties:
> +
> +- smmu-force-memtype : A list of StreamIDs which not translate address but
> +                  translate attributes. The StreamIDs list here can not be
> +                  used for map(translation) mode again.
> +                  StreamID first, then the type list below:
> +                  1, cahceable, WBRAWA, Normal outer and inner write-back
> +                  2, non-cacheable, Normal outer and inner non-cacheable
> +                  3, device, nGnRE
> +                  others, bypass
> +
> +- smmu-bypass-vmid   : Specify which context bank is used for bypass mode.
> +                  If omit, vmid=255 is default. If bypass and map mode can
> +                  share a same S2CR, config vmid=0.

These don't feel like they belong in the device-tree to me. Is the list of
StreamIDs described in smmu-force-memtype a property of the hardware
configuration, or a software policy to allow you to generate cacheable
traffic for particular masters?

Will