[v3,13/17] ARM: Xen: Document UEFI support on Xen ARM virtual platforms
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Message ID 1453519184-11908-14-git-send-email-zhaoshenglong@huawei.com
State New, archived
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Commit Message

Shannon Zhao Jan. 23, 2016, 3:19 a.m. UTC
From: Shannon Zhao <shannon.zhao@linaro.org>

Add a "uefi" node under /hypervisor node in FDT, then Linux kernel could
scan this to get the UEFI information.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
---
CC: Rob Herring <robh@kernel.org>
---
 Documentation/devicetree/bindings/arm/xen.txt | 34 +++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

Comments

Stefano Stabellini Jan. 25, 2016, 3:50 p.m. UTC | #1
On Sat, 23 Jan 2016, Shannon Zhao wrote:
> From: Shannon Zhao <shannon.zhao@linaro.org>
> 
> Add a "uefi" node under /hypervisor node in FDT, then Linux kernel could
> scan this to get the UEFI information.
> 
> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> Acked-by: Rob Herring <robh@kernel.org>
> ---
> CC: Rob Herring <robh@kernel.org>
> ---
>  Documentation/devicetree/bindings/arm/xen.txt | 34 +++++++++++++++++++++++++++
>  1 file changed, 34 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/xen.txt b/Documentation/devicetree/bindings/arm/xen.txt
> index 0f7b9c2..aa69405 100644
> --- a/Documentation/devicetree/bindings/arm/xen.txt
> +++ b/Documentation/devicetree/bindings/arm/xen.txt
> @@ -15,6 +15,26 @@ the following properties:
>  - interrupts: the interrupt used by Xen to inject event notifications.
>    A GIC node is also required.
>  
> +To support UEFI on Xen ARM virtual platforms, Xen populates the FDT "uefi" node
> +under /hypervisor with following parameters:
> +
> +________________________________________________________________________________
> +Name                      | Size   | Description
> +================================================================================
> +xen,uefi-system-table     | 64-bit | Guest physical address of the UEFI System
> +			  |	   | Table.
> +--------------------------------------------------------------------------------
> +xen,uefi-mmap-start       | 64-bit | Guest physical address of the UEFI memory
> +			  |	   | map.
> +--------------------------------------------------------------------------------
> +xen,uefi-mmap-size        | 32-bit | Size in bytes of the UEFI memory map
> +                          |        | pointed to in previous entry.
> +--------------------------------------------------------------------------------
> +xen,uefi-mmap-desc-size   | 32-bit | Size in bytes of each entry in the UEFI
> +                          |        | memory map.
> +--------------------------------------------------------------------------------
> +xen,uefi-mmap-desc-ver    | 32-bit | Version of the mmap descriptor format.
> +--------------------------------------------------------------------------------
>  
>  Example (assuming #address-cells = <2> and #size-cells = <2>):
>  
> @@ -22,4 +42,18 @@ hypervisor {
>  	compatible = "xen,xen-4.3", "xen,xen";
>  	reg = <0 0xb0000000 0 0x20000>;
>  	interrupts = <1 15 0xf08>;
> +	uefi {
> +		xen,uefi-system-table = <0xXXXXXXXX>;
> +		xen,uefi-mmap-start = <0xXXXXXXXX>;
> +		xen,uefi-mmap-size = <0xXXXXXXXX>;
> +		xen,uefi-mmap-desc-size = <0xXXXXXXXX>;
> +		xen,uefi-mmap-desc-ver = <0xXXXXXXXX>;
> +        };
>  };
> +
> +The format and meaning of these "xen,uefi-*" parameters are similar to those in
> +Documentation/arm/uefi.txt which are used by normal UEFI. But to distinguish
> +from normal UEFI, for Xen ARM virtual platforms it needs to introduce a Xen
> +specific UEFI which requires Xen hypervisor to provide hypercalls for Dom0 to
> +make use of the runtime services. Therefore, it defines these parameters under
> +/hypervisor node.

Please replace the paragraph with the following which mentions
include/xen/interface/platform.h and improves the wording:

"The format and meaning of the "xen,uefi-*" parameters are similar to
those in Documentation/arm/uefi.txt, which are provided by the regular
UEFI stub. However they differ because they are provided by the Xen
hypervisor, together with a set of UEFI runtime services implemented via
hypercalls, see include/xen/interface/platform.h."
Mark Rutland Jan. 25, 2016, 3:59 p.m. UTC | #2
On Mon, Jan 25, 2016 at 03:50:52PM +0000, Stefano Stabellini wrote:
> On Sat, 23 Jan 2016, Shannon Zhao wrote:
> > From: Shannon Zhao <shannon.zhao@linaro.org>
> > 
> > Add a "uefi" node under /hypervisor node in FDT, then Linux kernel could
> > scan this to get the UEFI information.
> > 
> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> > Acked-by: Rob Herring <robh@kernel.org>
> > ---
> > CC: Rob Herring <robh@kernel.org>
> > ---
> >  Documentation/devicetree/bindings/arm/xen.txt | 34 +++++++++++++++++++++++++++
> >  1 file changed, 34 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/arm/xen.txt b/Documentation/devicetree/bindings/arm/xen.txt
> > index 0f7b9c2..aa69405 100644
> > --- a/Documentation/devicetree/bindings/arm/xen.txt
> > +++ b/Documentation/devicetree/bindings/arm/xen.txt
> > @@ -15,6 +15,26 @@ the following properties:
> >  - interrupts: the interrupt used by Xen to inject event notifications.
> >    A GIC node is also required.
> >  
> > +To support UEFI on Xen ARM virtual platforms, Xen populates the FDT "uefi" node
> > +under /hypervisor with following parameters:
> > +
> > +________________________________________________________________________________
> > +Name                      | Size   | Description
> > +================================================================================
> > +xen,uefi-system-table     | 64-bit | Guest physical address of the UEFI System
> > +			  |	   | Table.
> > +--------------------------------------------------------------------------------
> > +xen,uefi-mmap-start       | 64-bit | Guest physical address of the UEFI memory
> > +			  |	   | map.
> > +--------------------------------------------------------------------------------
> > +xen,uefi-mmap-size        | 32-bit | Size in bytes of the UEFI memory map
> > +                          |        | pointed to in previous entry.
> > +--------------------------------------------------------------------------------
> > +xen,uefi-mmap-desc-size   | 32-bit | Size in bytes of each entry in the UEFI
> > +                          |        | memory map.
> > +--------------------------------------------------------------------------------
> > +xen,uefi-mmap-desc-ver    | 32-bit | Version of the mmap descriptor format.
> > +--------------------------------------------------------------------------------
> >  
> >  Example (assuming #address-cells = <2> and #size-cells = <2>):
> >  
> > @@ -22,4 +42,18 @@ hypervisor {
> >  	compatible = "xen,xen-4.3", "xen,xen";
> >  	reg = <0 0xb0000000 0 0x20000>;
> >  	interrupts = <1 15 0xf08>;
> > +	uefi {
> > +		xen,uefi-system-table = <0xXXXXXXXX>;
> > +		xen,uefi-mmap-start = <0xXXXXXXXX>;
> > +		xen,uefi-mmap-size = <0xXXXXXXXX>;
> > +		xen,uefi-mmap-desc-size = <0xXXXXXXXX>;
> > +		xen,uefi-mmap-desc-ver = <0xXXXXXXXX>;
> > +        };
> >  };
> > +
> > +The format and meaning of these "xen,uefi-*" parameters are similar to those in
> > +Documentation/arm/uefi.txt which are used by normal UEFI. But to distinguish
> > +from normal UEFI, for Xen ARM virtual platforms it needs to introduce a Xen
> > +specific UEFI which requires Xen hypervisor to provide hypercalls for Dom0 to
> > +make use of the runtime services. Therefore, it defines these parameters under
> > +/hypervisor node.
> 
> Please replace the paragraph with the following which mentions
> include/xen/interface/platform.h and improves the wording:
> 
> "The format and meaning of the "xen,uefi-*" parameters are similar to
> those in Documentation/arm/uefi.txt, which are provided by the regular
> UEFI stub. However they differ because they are provided by the Xen
> hypervisor, together with a set of UEFI runtime services implemented via
> hypercalls, see include/xen/interface/platform.h."

I would prefer if we didn't refer to Linux paths here, for the usual
rationale of keeping bindings distinct from Linux implementation
details.

Could we either drop the "see include/xen/interface/platform.h" part, or
refer to some Xen documentation?

Thanks,
Mark.
Stefano Stabellini Jan. 25, 2016, 4:06 p.m. UTC | #3
On Mon, 25 Jan 2016, Mark Rutland wrote:
> On Mon, Jan 25, 2016 at 03:50:52PM +0000, Stefano Stabellini wrote:
> > On Sat, 23 Jan 2016, Shannon Zhao wrote:
> > > From: Shannon Zhao <shannon.zhao@linaro.org>
> > > 
> > > Add a "uefi" node under /hypervisor node in FDT, then Linux kernel could
> > > scan this to get the UEFI information.
> > > 
> > > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> > > Acked-by: Rob Herring <robh@kernel.org>
> > > ---
> > > CC: Rob Herring <robh@kernel.org>
> > > ---
> > >  Documentation/devicetree/bindings/arm/xen.txt | 34 +++++++++++++++++++++++++++
> > >  1 file changed, 34 insertions(+)
> > > 
> > > diff --git a/Documentation/devicetree/bindings/arm/xen.txt b/Documentation/devicetree/bindings/arm/xen.txt
> > > index 0f7b9c2..aa69405 100644
> > > --- a/Documentation/devicetree/bindings/arm/xen.txt
> > > +++ b/Documentation/devicetree/bindings/arm/xen.txt
> > > @@ -15,6 +15,26 @@ the following properties:
> > >  - interrupts: the interrupt used by Xen to inject event notifications.
> > >    A GIC node is also required.
> > >  
> > > +To support UEFI on Xen ARM virtual platforms, Xen populates the FDT "uefi" node
> > > +under /hypervisor with following parameters:
> > > +
> > > +________________________________________________________________________________
> > > +Name                      | Size   | Description
> > > +================================================================================
> > > +xen,uefi-system-table     | 64-bit | Guest physical address of the UEFI System
> > > +			  |	   | Table.
> > > +--------------------------------------------------------------------------------
> > > +xen,uefi-mmap-start       | 64-bit | Guest physical address of the UEFI memory
> > > +			  |	   | map.
> > > +--------------------------------------------------------------------------------
> > > +xen,uefi-mmap-size        | 32-bit | Size in bytes of the UEFI memory map
> > > +                          |        | pointed to in previous entry.
> > > +--------------------------------------------------------------------------------
> > > +xen,uefi-mmap-desc-size   | 32-bit | Size in bytes of each entry in the UEFI
> > > +                          |        | memory map.
> > > +--------------------------------------------------------------------------------
> > > +xen,uefi-mmap-desc-ver    | 32-bit | Version of the mmap descriptor format.
> > > +--------------------------------------------------------------------------------
> > >  
> > >  Example (assuming #address-cells = <2> and #size-cells = <2>):
> > >  
> > > @@ -22,4 +42,18 @@ hypervisor {
> > >  	compatible = "xen,xen-4.3", "xen,xen";
> > >  	reg = <0 0xb0000000 0 0x20000>;
> > >  	interrupts = <1 15 0xf08>;
> > > +	uefi {
> > > +		xen,uefi-system-table = <0xXXXXXXXX>;
> > > +		xen,uefi-mmap-start = <0xXXXXXXXX>;
> > > +		xen,uefi-mmap-size = <0xXXXXXXXX>;
> > > +		xen,uefi-mmap-desc-size = <0xXXXXXXXX>;
> > > +		xen,uefi-mmap-desc-ver = <0xXXXXXXXX>;
> > > +        };
> > >  };
> > > +
> > > +The format and meaning of these "xen,uefi-*" parameters are similar to those in
> > > +Documentation/arm/uefi.txt which are used by normal UEFI. But to distinguish
> > > +from normal UEFI, for Xen ARM virtual platforms it needs to introduce a Xen
> > > +specific UEFI which requires Xen hypervisor to provide hypercalls for Dom0 to
> > > +make use of the runtime services. Therefore, it defines these parameters under
> > > +/hypervisor node.
> > 
> > Please replace the paragraph with the following which mentions
> > include/xen/interface/platform.h and improves the wording:
> > 
> > "The format and meaning of the "xen,uefi-*" parameters are similar to
> > those in Documentation/arm/uefi.txt, which are provided by the regular
> > UEFI stub. However they differ because they are provided by the Xen
> > hypervisor, together with a set of UEFI runtime services implemented via
> > hypercalls, see include/xen/interface/platform.h."
> 
> I would prefer if we didn't refer to Linux paths here, for the usual
> rationale of keeping bindings distinct from Linux implementation
> details.
> 
> Could we either drop the "see include/xen/interface/platform.h" part, or
> refer to some Xen documentation?

Sure, in fact the canonical headers are the ones in the Xen tree anyway.
We could use the following instead:

http://xenbits.xen.org/docs/unstable/hypercall/x86_64/include,public,platform.h.html

Patch
diff mbox

diff --git a/Documentation/devicetree/bindings/arm/xen.txt b/Documentation/devicetree/bindings/arm/xen.txt
index 0f7b9c2..aa69405 100644
--- a/Documentation/devicetree/bindings/arm/xen.txt
+++ b/Documentation/devicetree/bindings/arm/xen.txt
@@ -15,6 +15,26 @@  the following properties:
 - interrupts: the interrupt used by Xen to inject event notifications.
   A GIC node is also required.
 
+To support UEFI on Xen ARM virtual platforms, Xen populates the FDT "uefi" node
+under /hypervisor with following parameters:
+
+________________________________________________________________________________
+Name                      | Size   | Description
+================================================================================
+xen,uefi-system-table     | 64-bit | Guest physical address of the UEFI System
+			  |	   | Table.
+--------------------------------------------------------------------------------
+xen,uefi-mmap-start       | 64-bit | Guest physical address of the UEFI memory
+			  |	   | map.
+--------------------------------------------------------------------------------
+xen,uefi-mmap-size        | 32-bit | Size in bytes of the UEFI memory map
+                          |        | pointed to in previous entry.
+--------------------------------------------------------------------------------
+xen,uefi-mmap-desc-size   | 32-bit | Size in bytes of each entry in the UEFI
+                          |        | memory map.
+--------------------------------------------------------------------------------
+xen,uefi-mmap-desc-ver    | 32-bit | Version of the mmap descriptor format.
+--------------------------------------------------------------------------------
 
 Example (assuming #address-cells = <2> and #size-cells = <2>):
 
@@ -22,4 +42,18 @@  hypervisor {
 	compatible = "xen,xen-4.3", "xen,xen";
 	reg = <0 0xb0000000 0 0x20000>;
 	interrupts = <1 15 0xf08>;
+	uefi {
+		xen,uefi-system-table = <0xXXXXXXXX>;
+		xen,uefi-mmap-start = <0xXXXXXXXX>;
+		xen,uefi-mmap-size = <0xXXXXXXXX>;
+		xen,uefi-mmap-desc-size = <0xXXXXXXXX>;
+		xen,uefi-mmap-desc-ver = <0xXXXXXXXX>;
+        };
 };
+
+The format and meaning of these "xen,uefi-*" parameters are similar to those in
+Documentation/arm/uefi.txt which are used by normal UEFI. But to distinguish
+from normal UEFI, for Xen ARM virtual platforms it needs to introduce a Xen
+specific UEFI which requires Xen hypervisor to provide hypercalls for Dom0 to
+make use of the runtime services. Therefore, it defines these parameters under
+/hypervisor node.