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* [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled
@ 2016-04-19  5:59 Dirk Behme
  2016-04-19  5:59 ` [PATCH 2/2] xen: arm64: doc: Add some details about interrupt handling Dirk Behme
  2016-04-20 13:21 ` [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled Julien Grall
  0 siblings, 2 replies; 8+ messages in thread
From: Dirk Behme @ 2016-04-19  5:59 UTC (permalink / raw)
  To: xen-devel; +Cc: julien.grall, Dirk Behme

On ARM64 Linux the HVC instruction is used to trap into Xen. As this
can be set only at EL3, i.e. outside from Xen, document this boot
requirement.

Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
---
 docs/misc/arm/booting.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt
index 9802e5e..ffc9029 100644
--- a/docs/misc/arm/booting.txt
+++ b/docs/misc/arm/booting.txt
@@ -23,6 +23,10 @@ The exceptions to this on 32-bit ARM are as follows:
 
 There are no exception on 64-bit ARM.
 
+On ARM64 Linux it has to be ensured that the Secure Configuration
+Register has the HVC instructions enabled at EL1 and above
+(SCR_EL3.HCE == 1).
+
 [1] linux/Documentation/arm/Booting
 Latest version: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/arm/Booting
 
-- 
2.8.0


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

^ permalink raw reply related	[flat|nested] 8+ messages in thread

* [PATCH 2/2] xen: arm64: doc: Add some details about interrupt handling
  2016-04-19  5:59 [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled Dirk Behme
@ 2016-04-19  5:59 ` Dirk Behme
  2016-04-20 13:26   ` Julien Grall
  2016-04-20 13:21 ` [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled Julien Grall
  1 sibling, 1 reply; 8+ messages in thread
From: Dirk Behme @ 2016-04-19  5:59 UTC (permalink / raw)
  To: xen-devel; +Cc: julien.grall, Dirk Behme

In some mailing list discussion

http://lists.xen.org/archives/html/xen-devel/2016-04/msg00214.html

some details about the interrupt handling of Xen were given.
Add that so it's not forgotten.

Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
---
Note: I'd be happy to move this to an other documentation file if
      any other file fits better.

 docs/misc/arm/booting.txt | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt
index ffc9029..69b7d81 100644
--- a/docs/misc/arm/booting.txt
+++ b/docs/misc/arm/booting.txt
@@ -27,6 +27,21 @@ On ARM64 Linux it has to be ensured that the Secure Configuration
 Register has the HVC instructions enabled at EL1 and above
 (SCR_EL3.HCE == 1).
 
+
+Interrupt usage
+===============
+
+All interrupts are taken by Xen. The function do_IRQ in Xen will
+dispatch the IRQ either to a guest or call a Xen specific handler.
+
+Xen handles only a limited number of interrupt:
+* timers
+* UART
+* SMMU
+
+The rest is either routed to guests or blacklisted by Xen.
+
+
 [1] linux/Documentation/arm/Booting
 Latest version: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/arm/Booting
 
-- 
2.8.0


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

^ permalink raw reply related	[flat|nested] 8+ messages in thread

* Re: [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled
  2016-04-19  5:59 [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled Dirk Behme
  2016-04-19  5:59 ` [PATCH 2/2] xen: arm64: doc: Add some details about interrupt handling Dirk Behme
@ 2016-04-20 13:21 ` Julien Grall
  2016-04-22  6:23   ` Dirk Behme
  1 sibling, 1 reply; 8+ messages in thread
From: Julien Grall @ 2016-04-20 13:21 UTC (permalink / raw)
  To: Dirk Behme, xen-devel; +Cc: Stefano Stabellini, Ian Jackson, Jan Beulich

(CC REST maintainers)

Hello Dirk,

Please CC the relevant maintainers for this patch. You can use 
scripts/get_maintainers.pl for this purpose.

On 19/04/16 06:59, Dirk Behme wrote:
> On ARM64 Linux the HVC instruction is used to trap into Xen. As this
> can be set only at EL3, i.e. outside from Xen, document this boot
> requirement.
>
> Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
> ---
>   docs/misc/arm/booting.txt | 4 ++++
>   1 file changed, 4 insertions(+)
>
> diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt
> index 9802e5e..ffc9029 100644
> --- a/docs/misc/arm/booting.txt
> +++ b/docs/misc/arm/booting.txt
> @@ -23,6 +23,10 @@ The exceptions to this on 32-bit ARM are as follows:
>
>   There are no exception on 64-bit ARM.
>
> +On ARM64 Linux it has to be ensured that the Secure Configuration
> +Register has the HVC instructions enabled at EL1 and above
> +(SCR_EL3.HCE == 1).

The requirement is the same for ARM32 (SCR.HCE == 1).

I would create a specific section in this documentation to list what the 
firmware should do in EL3 before starting Xen.

In addition to this patch, I would add a check in Xen to make sure the 
Hyp calls have been enabled by the firmware.

Regards,

> +
>   [1] linux/Documentation/arm/Booting
>   Latest version: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/arm/Booting
>
>

-- 
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 2/2] xen: arm64: doc: Add some details about interrupt handling
  2016-04-19  5:59 ` [PATCH 2/2] xen: arm64: doc: Add some details about interrupt handling Dirk Behme
@ 2016-04-20 13:26   ` Julien Grall
  2016-04-25  8:56     ` Dirk Behme
  0 siblings, 1 reply; 8+ messages in thread
From: Julien Grall @ 2016-04-20 13:26 UTC (permalink / raw)
  To: Dirk Behme, xen-devel, Stefano Stabellini

Hello Dirk,

On 19/04/16 06:59, Dirk Behme wrote:
> In some mailing list discussion
>
> http://lists.xen.org/archives/html/xen-devel/2016-04/msg00214.html
>
> some details about the interrupt handling of Xen were given.
> Add that so it's not forgotten.

For your information, this is described on the wiki [1]. Although, not 
in the most obvious place.

I would prefer to see this kind of documentation on the wiki page under 
"Porting Xen on a new SOC".

>
> Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
> ---
> Note: I'd be happy to move this to an other documentation file if
>        any other file fits better.
>
>   docs/misc/arm/booting.txt | 15 +++++++++++++++
>   1 file changed, 15 insertions(+)
>
> diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt
> index ffc9029..69b7d81 100644
> --- a/docs/misc/arm/booting.txt
> +++ b/docs/misc/arm/booting.txt
> @@ -27,6 +27,21 @@ On ARM64 Linux it has to be ensured that the Secure Configuration
>   Register has the HVC instructions enabled at EL1 and above
>   (SCR_EL3.HCE == 1).
>
> +
> +Interrupt usage
> +===============
> +
> +All interrupts are taken by Xen. The function do_IRQ in Xen will
> +dispatch the IRQ either to a guest or call a Xen specific handler.
> +
> +Xen handles only a limited number of interrupt:
> +* timers
> +* UART
> +* SMMU
> +
> +The rest is either routed to guests or blacklisted by Xen.
> +
> +
>   [1] linux/Documentation/arm/Booting
>   Latest version: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/arm/Booting
>
>

Regards,

[1] 
http://wiki.xenproject.org/wiki/Xen_ARM_with_Virtualization_Extensions_whitepaper

-- 
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled
  2016-04-20 13:21 ` [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled Julien Grall
@ 2016-04-22  6:23   ` Dirk Behme
  2016-04-22  9:16     ` Julien Grall
  0 siblings, 1 reply; 8+ messages in thread
From: Dirk Behme @ 2016-04-22  6:23 UTC (permalink / raw)
  To: Julien Grall, xen-devel; +Cc: Stefano Stabellini, Ian Jackson, Jan Beulich

On 20.04.2016 15:21, Julien Grall wrote:
> (CC REST maintainers)
>
> Hello Dirk,
>
> Please CC the relevant maintainers for this patch. You can use
> scripts/get_maintainers.pl for this purpose.
>
> On 19/04/16 06:59, Dirk Behme wrote:
>> On ARM64 Linux the HVC instruction is used to trap into Xen. As this
>> can be set only at EL3, i.e. outside from Xen, document this boot
>> requirement.
>>
>> Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
>> ---
>>   docs/misc/arm/booting.txt | 4 ++++
>>   1 file changed, 4 insertions(+)
>>
>> diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt
>> index 9802e5e..ffc9029 100644
>> --- a/docs/misc/arm/booting.txt
>> +++ b/docs/misc/arm/booting.txt
>> @@ -23,6 +23,10 @@ The exceptions to this on 32-bit ARM are as follows:
>>
>>   There are no exception on 64-bit ARM.
>>
>> +On ARM64 Linux it has to be ensured that the Secure Configuration
>> +Register has the HVC instructions enabled at EL1 and above
>> +(SCR_EL3.HCE == 1).
>
> The requirement is the same for ARM32 (SCR.HCE == 1).
>
> I would create a specific section in this documentation to list what the
> firmware should do in EL3 before starting Xen.


Done:

http://lists.xen.org/archives/html/xen-devel/2016-04/msg02687.html


> In addition to this patch, I would add a check in Xen to make sure the
> Hyp calls have been enabled by the firmware.


Hmm, I have to re-read the documentation how to do this in EL2. We can't 
read SCR_EL3 in EL2?


Best regards

Dirk


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled
  2016-04-22  6:23   ` Dirk Behme
@ 2016-04-22  9:16     ` Julien Grall
  0 siblings, 0 replies; 8+ messages in thread
From: Julien Grall @ 2016-04-22  9:16 UTC (permalink / raw)
  To: Dirk Behme, xen-devel; +Cc: Stefano Stabellini

Hi Dirk,

On 22/04/2016 07:23, Dirk Behme wrote:
> On 20.04.2016 15:21, Julien Grall wrote:
>> I would create a specific section in this documentation to list what the
>> firmware should do in EL3 before starting Xen.
>
>
> Done:
>
> http://lists.xen.org/archives/html/xen-devel/2016-04/msg02687.html

Thank you, I will look at it soon.

>
>> In addition to this patch, I would add a check in Xen to make sure the
>> Hyp calls have been enabled by the firmware.
>
>
> Hmm, I have to re-read the documentation how to do this in EL2. We can't
> read SCR_EL3 in EL2?

Oh yes. sorry I would have thought the register would be exposed RO to EL2.

Regards,

-- 
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 2/2] xen: arm64: doc: Add some details about interrupt handling
  2016-04-20 13:26   ` Julien Grall
@ 2016-04-25  8:56     ` Dirk Behme
  2016-04-25 11:06       ` Julien Grall
  0 siblings, 1 reply; 8+ messages in thread
From: Dirk Behme @ 2016-04-25  8:56 UTC (permalink / raw)
  To: Julien Grall, Dirk Behme, xen-devel, Stefano Stabellini

Hi Julien,

On 20.04.2016 15:26, Julien Grall wrote:
> Hello Dirk,
>
> On 19/04/16 06:59, Dirk Behme wrote:
>> In some mailing list discussion
>>
>> http://lists.xen.org/archives/html/xen-devel/2016-04/msg00214.html
>>
>> some details about the interrupt handling of Xen were given.
>> Add that so it's not forgotten.
>
> For your information, this is described on the wiki [1]. Although, not
> in the most obvious place.
>
> I would prefer to see this kind of documentation on the wiki page
> under "Porting Xen on a new SOC".


Anything like

http://wiki.xenproject.org/wiki?title=Xen_ARM_with_Virtualization_Extensions_whitepaper&diff=16710&oldid=11342

?

Best regards

Dirk


>>
>> Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
>> ---
>> Note: I'd be happy to move this to an other documentation file if
>>        any other file fits better.
>>
>>   docs/misc/arm/booting.txt | 15 +++++++++++++++
>>   1 file changed, 15 insertions(+)
>>
>> diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt
>> index ffc9029..69b7d81 100644
>> --- a/docs/misc/arm/booting.txt
>> +++ b/docs/misc/arm/booting.txt
>> @@ -27,6 +27,21 @@ On ARM64 Linux it has to be ensured that the
>> Secure Configuration
>>   Register has the HVC instructions enabled at EL1 and above
>>   (SCR_EL3.HCE == 1).
>>
>> +
>> +Interrupt usage
>> +===============
>> +
>> +All interrupts are taken by Xen. The function do_IRQ in Xen will
>> +dispatch the IRQ either to a guest or call a Xen specific handler.
>> +
>> +Xen handles only a limited number of interrupt:
>> +* timers
>> +* UART
>> +* SMMU
>> +
>> +The rest is either routed to guests or blacklisted by Xen.
>> +
>> +
>>   [1] linux/Documentation/arm/Booting
>>   Latest version:
>> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/arm/Booting
>>
>>
>>
>
> Regards,
>
> [1]
> http://wiki.xenproject.org/wiki/Xen_ARM_with_Virtualization_Extensions_whitepaper
>
>


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 2/2] xen: arm64: doc: Add some details about interrupt handling
  2016-04-25  8:56     ` Dirk Behme
@ 2016-04-25 11:06       ` Julien Grall
  0 siblings, 0 replies; 8+ messages in thread
From: Julien Grall @ 2016-04-25 11:06 UTC (permalink / raw)
  To: Dirk Behme, Dirk Behme, xen-devel, Stefano Stabellini



On 25/04/16 09:56, Dirk Behme wrote:
> Hi Julien,

Hello Dirk,

> On 20.04.2016 15:26, Julien Grall wrote:
>> On 19/04/16 06:59, Dirk Behme wrote:
>>> In some mailing list discussion
>>>
>>> http://lists.xen.org/archives/html/xen-devel/2016-04/msg00214.html
>>>
>>> some details about the interrupt handling of Xen were given.
>>> Add that so it's not forgotten.
>>
>> For your information, this is described on the wiki [1]. Although, not
>> in the most obvious place.
>>
>> I would prefer to see this kind of documentation on the wiki page
>> under "Porting Xen on a new SOC".
>
>
> Anything like
>
> http://wiki.xenproject.org/wiki?title=Xen_ARM_with_Virtualization_Extensions_whitepaper&diff=16710&oldid=11342

It sounds good for me.

Regards,

-- 
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

^ permalink raw reply	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2016-04-25 11:06 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-04-19  5:59 [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled Dirk Behme
2016-04-19  5:59 ` [PATCH 2/2] xen: arm64: doc: Add some details about interrupt handling Dirk Behme
2016-04-20 13:26   ` Julien Grall
2016-04-25  8:56     ` Dirk Behme
2016-04-25 11:06       ` Julien Grall
2016-04-20 13:21 ` [PATCH 1/2] xen: arm64: doc: Add the requirement that SCR_EL3.HCE is enabled Julien Grall
2016-04-22  6:23   ` Dirk Behme
2016-04-22  9:16     ` Julien Grall

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