[PATCH] arm/docs: Clarify legacy DT bindings on UEFI

Luca Fancellu posted 1 patch 1 week, 2 days ago
docs/misc/arm/device-tree/booting.txt | 2 ++
1 file changed, 2 insertions(+)

[PATCH] arm/docs: Clarify legacy DT bindings on UEFI

Posted by Luca Fancellu 1 week, 2 days ago
Legacy compatible strings for dom0 modules are not
supported when booting using UEFI, the documentation
doesn't mention that.

Add a phrase to docs/misc/arm/device-tree/booting.txt
to clarify it.

Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
---
 docs/misc/arm/device-tree/booting.txt | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
index c6a775f4e8..017c0f13eb 100644
--- a/docs/misc/arm/device-tree/booting.txt
+++ b/docs/misc/arm/device-tree/booting.txt
@@ -51,6 +51,8 @@ Each node contains the following properties:
 	Xen 4.4 supported a different set of legacy compatible strings
 	which remain supported such that systems supporting both 4.4
 	and later can use a single DTB.
+	However when booting Xen using UEFI and Device Tree, the legacy
+	compatible strings are not supported.
 
 	- "xen,multiboot-module" equivalent to "multiboot,module"
 	- "xen,linux-zimage"     equivalent to "multiboot,kernel"
-- 
2.17.1


Re: [PATCH] arm/docs: Clarify legacy DT bindings on UEFI

Posted by Julien Grall 1 week, 2 days ago
Hi Luca,

On 13/10/2021 13:19, Luca Fancellu wrote:
> Legacy compatible strings for dom0 modules are not
> supported when booting using UEFI, the documentation
> doesn't mention that.

Can you add a summary in the commit message why we consider the legacy 
binding is not supported?

> 
> Add a phrase to docs/misc/arm/device-tree/booting.txt
> to clarify it.
> 
> Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
> ---
>   docs/misc/arm/device-tree/booting.txt | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
> index c6a775f4e8..017c0f13eb 100644
> --- a/docs/misc/arm/device-tree/booting.txt
> +++ b/docs/misc/arm/device-tree/booting.txt
> @@ -51,6 +51,8 @@ Each node contains the following properties:
>   	Xen 4.4 supported a different set of legacy compatible strings
>   	which remain supported such that systems supporting both 4.4
>   	and later can use a single DTB.
> +	However when booting Xen using UEFI and Device Tree, the legacy

NIT: I would drop "and Device Tree" because this feels a bit redundant 
as this compatible can only be used in the Device-Tree.

> +	compatible strings are not supported.
>   
>   	- "xen,multiboot-module" equivalent to "multiboot,module"
>   	- "xen,linux-zimage"     equivalent to "multiboot,kernel"
> 

Cheers,

-- 
Julien Grall

Re: [PATCH] arm/docs: Clarify legacy DT bindings on UEFI

Posted by Luca Fancellu 1 week, 2 days ago

> On 13 Oct 2021, at 14:27, Julien Grall <julien@xen.org> wrote:
> 
> Hi Luca,
> 
> On 13/10/2021 13:19, Luca Fancellu wrote:
>> Legacy compatible strings for dom0 modules are not
>> supported when booting using UEFI, the documentation
>> doesn't mention that.
> 
> Can you add a summary in the commit message why we consider the legacy binding is not supported?

Yes what about:

Since the introduction of UEFI boot for Xen, the legacy
compatible strings were not supported and the stub code
was checking only the presence of “multiboot,module” to
require the Xen UEFI configuration file or not.
The documentation was not updated to specify that behavior.

Add a phrase to docs/misc/arm/device-tree/booting.txt
to clarify it.

> 
>> Add a phrase to docs/misc/arm/device-tree/booting.txt
>> to clarify it.
>> Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
>> ---
>>  docs/misc/arm/device-tree/booting.txt | 2 ++
>>  1 file changed, 2 insertions(+)
>> diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
>> index c6a775f4e8..017c0f13eb 100644
>> --- a/docs/misc/arm/device-tree/booting.txt
>> +++ b/docs/misc/arm/device-tree/booting.txt
>> @@ -51,6 +51,8 @@ Each node contains the following properties:
>>  	Xen 4.4 supported a different set of legacy compatible strings
>>  	which remain supported such that systems supporting both 4.4
>>  	and later can use a single DTB.
>> +	However when booting Xen using UEFI and Device Tree, the legacy
> 
> NIT: I would drop "and Device Tree" because this feels a bit redundant as this compatible can only be used in the Device-Tree.

I will drop it

> 
>> +	compatible strings are not supported.
>>    	- "xen,multiboot-module" equivalent to "multiboot,module"
>>  	- "xen,linux-zimage"     equivalent to "multiboot,kernel"
> 
> Cheers,
> 
> -- 
> Julien Grall


Re: [PATCH] arm/docs: Clarify legacy DT bindings on UEFI

Posted by Julien Grall 1 week, 1 day ago
Hi Luca,

On 13/10/2021 15:06, Luca Fancellu wrote:
> 
> 
>> On 13 Oct 2021, at 14:27, Julien Grall <julien@xen.org> wrote:
>>
>> Hi Luca,
>>
>> On 13/10/2021 13:19, Luca Fancellu wrote:
>>> Legacy compatible strings for dom0 modules are not
>>> supported when booting using UEFI, the documentation
>>> doesn't mention that.
>>
>> Can you add a summary in the commit message why we consider the legacy binding is not supported?
> 
> Yes what about:
> 
> Since the introduction of UEFI boot for Xen, the legacy
> compatible strings were not supported and the stub code
> was checking only the presence of “multiboot,module” to
> require the Xen UEFI configuration file or not.
> The documentation was not updated to specify that behavior.
> 
> Add a phrase to docs/misc/arm/device-tree/booting.txt
> to clarify it.

Sounds good to me. You can add my ack on it:

Acked-by: Julien Grall <jgrall@amazon.com>

Would you be able to respin the patch with the two changes?

> 
>>
>>> Add a phrase to docs/misc/arm/device-tree/booting.txt
>>> to clarify it.
>>> Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
>>> ---
>>>   docs/misc/arm/device-tree/booting.txt | 2 ++
>>>   1 file changed, 2 insertions(+)
>>> diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
>>> index c6a775f4e8..017c0f13eb 100644
>>> --- a/docs/misc/arm/device-tree/booting.txt
>>> +++ b/docs/misc/arm/device-tree/booting.txt
>>> @@ -51,6 +51,8 @@ Each node contains the following properties:
>>>   	Xen 4.4 supported a different set of legacy compatible strings
>>>   	which remain supported such that systems supporting both 4.4
>>>   	and later can use a single DTB.
>>> +	However when booting Xen using UEFI and Device Tree, the legacy
>>
>> NIT: I would drop "and Device Tree" because this feels a bit redundant as this compatible can only be used in the Device-Tree.
> 
> I will drop it
> 
>>
>>> +	compatible strings are not supported.
>>>     	- "xen,multiboot-module" equivalent to "multiboot,module"
>>>   	- "xen,linux-zimage"     equivalent to "multiboot,kernel"
>>
>> Cheers,
>>
>> -- 
>> Julien Grall
> 

Cheers,

-- 
Julien Grall

Re: [PATCH] arm/docs: Clarify legacy DT bindings on UEFI

Posted by Luca Fancellu 1 week, 1 day ago

> On 13 Oct 2021, at 15:30, Julien Grall <julien@xen.org> wrote:
> 
> Hi Luca,
> 
> On 13/10/2021 15:06, Luca Fancellu wrote:
>>> On 13 Oct 2021, at 14:27, Julien Grall <julien@xen.org> wrote:
>>> 
>>> Hi Luca,
>>> 
>>> On 13/10/2021 13:19, Luca Fancellu wrote:
>>>> Legacy compatible strings for dom0 modules are not
>>>> supported when booting using UEFI, the documentation
>>>> doesn't mention that.
>>> 
>>> Can you add a summary in the commit message why we consider the legacy binding is not supported?
>> Yes what about:
>> Since the introduction of UEFI boot for Xen, the legacy
>> compatible strings were not supported and the stub code
>> was checking only the presence of “multiboot,module” to
>> require the Xen UEFI configuration file or not.
>> The documentation was not updated to specify that behavior.
>> Add a phrase to docs/misc/arm/device-tree/booting.txt
>> to clarify it.
> 
> Sounds good to me. You can add my ack on it:
> 
> Acked-by: Julien Grall <jgrall@amazon.com>
> 
> Would you be able to respin the patch with the two changes?

Yes I will, thank you.

Cheers,
Luca

> 
>>> 
>>>> Add a phrase to docs/misc/arm/device-tree/booting.txt
>>>> to clarify it.
>>>> Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
>>>> ---
>>>>  docs/misc/arm/device-tree/booting.txt | 2 ++
>>>>  1 file changed, 2 insertions(+)
>>>> diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
>>>> index c6a775f4e8..017c0f13eb 100644
>>>> --- a/docs/misc/arm/device-tree/booting.txt
>>>> +++ b/docs/misc/arm/device-tree/booting.txt
>>>> @@ -51,6 +51,8 @@ Each node contains the following properties:
>>>>  	Xen 4.4 supported a different set of legacy compatible strings
>>>>  	which remain supported such that systems supporting both 4.4
>>>>  	and later can use a single DTB.
>>>> +	However when booting Xen using UEFI and Device Tree, the legacy
>>> 
>>> NIT: I would drop "and Device Tree" because this feels a bit redundant as this compatible can only be used in the Device-Tree.
>> I will drop it
>>> 
>>>> +	compatible strings are not supported.
>>>>    	- "xen,multiboot-module" equivalent to "multiboot,module"
>>>>  	- "xen,linux-zimage"     equivalent to "multiboot,kernel"
>>> 
>>> Cheers,
>>> 
>>> -- 
>>> Julien Grall
> 
> Cheers,
> 
> -- 
> Julien Grall