Document the ast2400, ast2500 PCI-to-AHB bridge control driver bindings.
Signed-off-by: Patrick Venture <[email protected]>
---
Changes for v7:
- Moved node under the syscon node it requires
Changes for v6:
- None
Changes for v5:
- None
Changes for v4:
- None
Changes for v3:
- None
Changes for v2:
- Added comment about syscon required parameter.
---
.../bindings/misc/aspeed-p2a-ctrl.txt | 48 +++++++++++++++++++
1 file changed, 48 insertions(+)
create mode 100644 Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt
diff --git a/Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt b/Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt
new file mode 100644
index 000000000000..088cc4e3dc54
--- /dev/null
+++ b/Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt
@@ -0,0 +1,48 @@
+======================================================================
+Device tree bindings for Aspeed AST2400/AST2500 PCI-to-AHB Bridge Control Driver
+======================================================================
+
+The bridge is available on platforms with the VGA enabled on the Aspeed device.
+In this case, the host has access to a 64KiB window into all of the BMC's
+memory. The BMC can disable this bridge. If the bridge is enabled, the host
+has read access to all the regions of memory, however the host only has read
+and write access depending on a register controlled by the BMC.
+
+Required properties:
+===================
+
+ - compatible: must be one of:
+ - "aspeed,ast2400-p2a-ctrl"
+ - "aspeed,ast2500-p2a-ctrl"
+
+ - syscon: handle to syscon device node controlling PCI.
+
+Optional properties:
+===================
+
+- memory-region: A phandle to a reserved_memory region to be used for the PCI
+ to AHB mapping
+
+The p2a-control node should be the child of a syscon node with the required
+property:
+
+- compatible : Should be one of the following:
+ "aspeed,ast2400-scu", "syscon", "simple-mfd"
+ "aspeed,g4-scu", "syscon", "simple-mfd"
+ "aspeed,ast2500-scu", "syscon", "simple-mfd"
+ "aspeed,g5-scu", "syscon", "simple-mfd"
+
+Example:
+
+g4 Example
+----------
+
+syscon: scu@1e6e2000 {
+ compatible = "aspeed,ast2400-scu", "syscon", "simple-mfd";
+ reg = <0x1e6e2000 0x1a8>;
+
+ p2a: p2a-control {
+ compatible = "aspeed,ast2400-p2a-ctrl";
+ memory-region = <&reserved_memory>;
+ };
+};
--
2.21.0.360.g471c308f928-goog
On Tue, Mar 12, 2019 at 11:30 AM Patrick Venture <[email protected]> wrote:
>
> Document the ast2400, ast2500 PCI-to-AHB bridge control driver bindings.
>
> Signed-off-by: Patrick Venture <[email protected]>
> ---
> Changes for v7:
> - Moved node under the syscon node it requires
> Changes for v6:
> - None
> Changes for v5:
> - None
> Changes for v4:
> - None
> Changes for v3:
> - None
> Changes for v2:
> - Added comment about syscon required parameter.
> ---
> .../bindings/misc/aspeed-p2a-ctrl.txt | 48 +++++++++++++++++++
> 1 file changed, 48 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt
>
> diff --git a/Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt b/Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt
> new file mode 100644
> index 000000000000..088cc4e3dc54
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt
> @@ -0,0 +1,48 @@
> +======================================================================
> +Device tree bindings for Aspeed AST2400/AST2500 PCI-to-AHB Bridge Control Driver
> +======================================================================
> +
> +The bridge is available on platforms with the VGA enabled on the Aspeed device.
> +In this case, the host has access to a 64KiB window into all of the BMC's
> +memory. The BMC can disable this bridge. If the bridge is enabled, the host
> +has read access to all the regions of memory, however the host only has read
> +and write access depending on a register controlled by the BMC.
> +
> +Required properties:
> +===================
> +
> + - compatible: must be one of:
> + - "aspeed,ast2400-p2a-ctrl"
> + - "aspeed,ast2500-p2a-ctrl"
> +
> + - syscon: handle to syscon device node controlling PCI.
> +
> +Optional properties:
> +===================
> +
> +- memory-region: A phandle to a reserved_memory region to be used for the PCI
> + to AHB mapping
> +
> +The p2a-control node should be the child of a syscon node with the required
> +property:
> +
> +- compatible : Should be one of the following:
> + "aspeed,ast2400-scu", "syscon", "simple-mfd"
> + "aspeed,g4-scu", "syscon", "simple-mfd"
> + "aspeed,ast2500-scu", "syscon", "simple-mfd"
> + "aspeed,g5-scu", "syscon", "simple-mfd"
> +
> +Example:
> +
> +g4 Example
> +----------
> +
> +syscon: scu@1e6e2000 {
> + compatible = "aspeed,ast2400-scu", "syscon", "simple-mfd";
> + reg = <0x1e6e2000 0x1a8>;
> +
> + p2a: p2a-control {
> + compatible = "aspeed,ast2400-p2a-ctrl";
If there's a defined register range, then you could add a reg property
(even though Linux doesn't use it).
Either way,
Reviewed-by: Rob Herring <[email protected]>
On Wed, Mar 13, 2019 at 12:54 PM Rob Herring <[email protected]> wrote:
>
> On Tue, Mar 12, 2019 at 11:30 AM Patrick Venture <[email protected]> wrote:
> >
> > Document the ast2400, ast2500 PCI-to-AHB bridge control driver bindings.
> >
> > Signed-off-by: Patrick Venture <[email protected]>
> > ---
> > Changes for v7:
> > - Moved node under the syscon node it requires
> > Changes for v6:
> > - None
> > Changes for v5:
> > - None
> > Changes for v4:
> > - None
> > Changes for v3:
> > - None
> > Changes for v2:
> > - Added comment about syscon required parameter.
> > ---
> > .../bindings/misc/aspeed-p2a-ctrl.txt | 48 +++++++++++++++++++
> > 1 file changed, 48 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt
> >
> > diff --git a/Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt b/Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt
> > new file mode 100644
> > index 000000000000..088cc4e3dc54
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/misc/aspeed-p2a-ctrl.txt
> > @@ -0,0 +1,48 @@
> > +======================================================================
> > +Device tree bindings for Aspeed AST2400/AST2500 PCI-to-AHB Bridge Control Driver
> > +======================================================================
> > +
> > +The bridge is available on platforms with the VGA enabled on the Aspeed device.
> > +In this case, the host has access to a 64KiB window into all of the BMC's
> > +memory. The BMC can disable this bridge. If the bridge is enabled, the host
> > +has read access to all the regions of memory, however the host only has read
> > +and write access depending on a register controlled by the BMC.
> > +
> > +Required properties:
> > +===================
> > +
> > + - compatible: must be one of:
> > + - "aspeed,ast2400-p2a-ctrl"
> > + - "aspeed,ast2500-p2a-ctrl"
> > +
> > + - syscon: handle to syscon device node controlling PCI.
> > +
> > +Optional properties:
> > +===================
> > +
> > +- memory-region: A phandle to a reserved_memory region to be used for the PCI
> > + to AHB mapping
> > +
> > +The p2a-control node should be the child of a syscon node with the required
> > +property:
> > +
> > +- compatible : Should be one of the following:
> > + "aspeed,ast2400-scu", "syscon", "simple-mfd"
> > + "aspeed,g4-scu", "syscon", "simple-mfd"
> > + "aspeed,ast2500-scu", "syscon", "simple-mfd"
> > + "aspeed,g5-scu", "syscon", "simple-mfd"
> > +
> > +Example:
> > +
> > +g4 Example
> > +----------
> > +
> > +syscon: scu@1e6e2000 {
> > + compatible = "aspeed,ast2400-scu", "syscon", "simple-mfd";
> > + reg = <0x1e6e2000 0x1a8>;
> > +
> > + p2a: p2a-control {
> > + compatible = "aspeed,ast2400-p2a-ctrl";
>
> If there's a defined register range, then you could add a reg property
> (even though Linux doesn't use it).
in this case, the device just needs access to two separate registers
controlled by the syscon to which it is now a child.
>
> Either way,
>
> Reviewed-by: Rob Herring <[email protected]>