[1/7,v6] Documentation: fsl-mc: add iommu-map device-tree binding for fsl-mc bus

Message ID 1531135103-10699-2-git-send-email-nipun.gupta@nxp.com
State New
Headers show
Series
  • Support for fsl-mc bus and its devices in SMMU
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Commit Message

Nipun Gupta July 9, 2018, 11:18 a.m.
The existing IOMMU bindings cannot be used to specify the relationship
between fsl-mc devices and IOMMUs. This patch adds a generic binding for
mapping fsl-mc devices to IOMMUs, using iommu-map property.

Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../devicetree/bindings/misc/fsl,qoriq-mc.txt      | 39 ++++++++++++++++++++++
 1 file changed, 39 insertions(+)

Comments

Robin Murphy July 25, 2018, 1 p.m. | #1
On 09/07/18 12:18, Nipun Gupta wrote:
> The existing IOMMU bindings cannot be used to specify the relationship
> between fsl-mc devices and IOMMUs. This patch adds a generic binding for
> mapping fsl-mc devices to IOMMUs, using iommu-map property.

No more nits from me :)

Acked-by: Robin Murphy <robin.murphy@arm.com>

> Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
> Reviewed-by: Rob Herring <robh@kernel.org>
> ---
>   .../devicetree/bindings/misc/fsl,qoriq-mc.txt      | 39 ++++++++++++++++++++++
>   1 file changed, 39 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt b/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt
> index 6611a7c..01fdc33 100644
> --- a/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt
> +++ b/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt
> @@ -9,6 +9,25 @@ blocks that can be used to create functional hardware objects/devices
>   such as network interfaces, crypto accelerator instances, L2 switches,
>   etc.
>   
> +For an overview of the DPAA2 architecture and fsl-mc bus see:
> +Documentation/networking/dpaa2/overview.rst
> +
> +As described in the above overview, all DPAA2 objects in a DPRC share the
> +same hardware "isolation context" and a 10-bit value called an ICID
> +(isolation context id) is expressed by the hardware to identify
> +the requester.
> +
> +The generic 'iommus' property is insufficient to describe the relationship
> +between ICIDs and IOMMUs, so an iommu-map property is used to define
> +the set of possible ICIDs under a root DPRC and how they map to
> +an IOMMU.
> +
> +For generic IOMMU bindings, see
> +Documentation/devicetree/bindings/iommu/iommu.txt.
> +
> +For arm-smmu binding, see:
> +Documentation/devicetree/bindings/iommu/arm,smmu.txt.
> +
>   Required properties:
>   
>       - compatible
> @@ -88,14 +107,34 @@ Sub-nodes:
>                 Value type: <phandle>
>                 Definition: Specifies the phandle to the PHY device node associated
>                             with the this dpmac.
> +Optional properties:
> +
> +- iommu-map: Maps an ICID to an IOMMU and associated iommu-specifier
> +  data.
> +
> +  The property is an arbitrary number of tuples of
> +  (icid-base,iommu,iommu-base,length).
> +
> +  Any ICID i in the interval [icid-base, icid-base + length) is
> +  associated with the listed IOMMU, with the iommu-specifier
> +  (i - icid-base + iommu-base).
>   
>   Example:
>   
> +        smmu: iommu@5000000 {
> +               compatible = "arm,mmu-500";
> +               #iommu-cells = <1>;
> +               stream-match-mask = <0x7C00>;
> +               ...
> +        };
> +
>           fsl_mc: fsl-mc@80c000000 {
>                   compatible = "fsl,qoriq-mc";
>                   reg = <0x00000008 0x0c000000 0 0x40>,    /* MC portal base */
>                         <0x00000000 0x08340000 0 0x40000>; /* MC control reg */
>                   msi-parent = <&its>;
> +                /* define map for ICIDs 23-64 */
> +                iommu-map = <23 &smmu 23 41>;
>                   #address-cells = <3>;
>                   #size-cells = <1>;
>   
>

Patch

diff --git a/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt b/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt
index 6611a7c..01fdc33 100644
--- a/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt
+++ b/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt
@@ -9,6 +9,25 @@  blocks that can be used to create functional hardware objects/devices
 such as network interfaces, crypto accelerator instances, L2 switches,
 etc.
 
+For an overview of the DPAA2 architecture and fsl-mc bus see:
+Documentation/networking/dpaa2/overview.rst
+
+As described in the above overview, all DPAA2 objects in a DPRC share the
+same hardware "isolation context" and a 10-bit value called an ICID
+(isolation context id) is expressed by the hardware to identify
+the requester.
+
+The generic 'iommus' property is insufficient to describe the relationship
+between ICIDs and IOMMUs, so an iommu-map property is used to define
+the set of possible ICIDs under a root DPRC and how they map to
+an IOMMU.
+
+For generic IOMMU bindings, see
+Documentation/devicetree/bindings/iommu/iommu.txt.
+
+For arm-smmu binding, see:
+Documentation/devicetree/bindings/iommu/arm,smmu.txt.
+
 Required properties:
 
     - compatible
@@ -88,14 +107,34 @@  Sub-nodes:
               Value type: <phandle>
               Definition: Specifies the phandle to the PHY device node associated
                           with the this dpmac.
+Optional properties:
+
+- iommu-map: Maps an ICID to an IOMMU and associated iommu-specifier
+  data.
+
+  The property is an arbitrary number of tuples of
+  (icid-base,iommu,iommu-base,length).
+
+  Any ICID i in the interval [icid-base, icid-base + length) is
+  associated with the listed IOMMU, with the iommu-specifier
+  (i - icid-base + iommu-base).
 
 Example:
 
+        smmu: iommu@5000000 {
+               compatible = "arm,mmu-500";
+               #iommu-cells = <1>;
+               stream-match-mask = <0x7C00>;
+               ...
+        };
+
         fsl_mc: fsl-mc@80c000000 {
                 compatible = "fsl,qoriq-mc";
                 reg = <0x00000008 0x0c000000 0 0x40>,    /* MC portal base */
                       <0x00000000 0x08340000 0 0x40000>; /* MC control reg */
                 msi-parent = <&its>;
+                /* define map for ICIDs 23-64 */
+                iommu-map = <23 &smmu 23 41>;
                 #address-cells = <3>;
                 #size-cells = <1>;