* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
@ 2016-01-27 23:10 dann frazier
2016-01-28 10:34 ` Catalin Marinas
2016-01-28 11:24 ` Mark Rutland
0 siblings, 2 replies; 9+ messages in thread
From: dann frazier @ 2016-01-27 23:10 UTC (permalink / raw)
To: linux-arm-kernel
16K page size is an optional feature of the architecture, and is not
supported by the X-Gene SoC family.
Signed-off-by: dann frazier <dann.frazier@canonical.com>
---
arch/arm64/Kconfig.platforms | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
index 21074f6..b241290 100644
--- a/arch/arm64/Kconfig.platforms
+++ b/arch/arm64/Kconfig.platforms
@@ -133,6 +133,7 @@ config ARCH_VEXPRESS
config ARCH_XGENE
bool "AppliedMicro X-Gene SOC Family"
+ depends on !ARM64_16K_PAGES
help
This enables support for AppliedMicro X-Gene SOC Family
--
2.7.0
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-27 23:10 [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size dann frazier
@ 2016-01-28 10:34 ` Catalin Marinas
2016-01-28 11:08 ` Will Deacon
2016-01-28 11:24 ` Mark Rutland
1 sibling, 1 reply; 9+ messages in thread
From: Catalin Marinas @ 2016-01-28 10:34 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
> 16K page size is an optional feature of the architecture, and is not
> supported by the X-Gene SoC family.
>
> Signed-off-by: dann frazier <dann.frazier@canonical.com>
> ---
> arch/arm64/Kconfig.platforms | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
> index 21074f6..b241290 100644
> --- a/arch/arm64/Kconfig.platforms
> +++ b/arch/arm64/Kconfig.platforms
> @@ -133,6 +133,7 @@ config ARCH_VEXPRESS
>
> config ARCH_XGENE
> bool "AppliedMicro X-Gene SOC Family"
> + depends on !ARM64_16K_PAGES
> help
> This enables support for AppliedMicro X-Gene SOC Family
This would be the case on Juno as well. But maybe at some point the
X-Gene family would gain a CPU with such support.
Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
harder to enable. We've had a few questions recently about enabling it
on CPUs that don't have such feature.
--
Catalin
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 10:34 ` Catalin Marinas
@ 2016-01-28 11:08 ` Will Deacon
2016-01-28 11:20 ` Mark Rutland
2016-01-28 11:27 ` Suzuki K. Poulose
0 siblings, 2 replies; 9+ messages in thread
From: Will Deacon @ 2016-01-28 11:08 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
> On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
> > 16K page size is an optional feature of the architecture, and is not
> > supported by the X-Gene SoC family.
> >
> > Signed-off-by: dann frazier <dann.frazier@canonical.com>
> > ---
> > arch/arm64/Kconfig.platforms | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
> > index 21074f6..b241290 100644
> > --- a/arch/arm64/Kconfig.platforms
> > +++ b/arch/arm64/Kconfig.platforms
> > @@ -133,6 +133,7 @@ config ARCH_VEXPRESS
> >
> > config ARCH_XGENE
> > bool "AppliedMicro X-Gene SOC Family"
> > + depends on !ARM64_16K_PAGES
> > help
> > This enables support for AppliedMicro X-Gene SOC Family
>
> This would be the case on Juno as well. But maybe at some point the
> X-Gene family would gain a CPU with such support.
>
> Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
> harder to enable. We've had a few questions recently about enabling it
> on CPUs that don't have such feature.
I thought there was also a suggestion that we could fail gracefully in
the EFI stub if we detected an unsupported page size?
Will
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 11:08 ` Will Deacon
@ 2016-01-28 11:20 ` Mark Rutland
2016-01-28 14:50 ` Jeremy Linton
2016-01-28 11:27 ` Suzuki K. Poulose
1 sibling, 1 reply; 9+ messages in thread
From: Mark Rutland @ 2016-01-28 11:20 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Jan 28, 2016 at 11:08:20AM +0000, Will Deacon wrote:
> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
> > On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
> > > 16K page size is an optional feature of the architecture, and is not
> > > supported by the X-Gene SoC family.
> > >
> > > Signed-off-by: dann frazier <dann.frazier@canonical.com>
> > > ---
> > > arch/arm64/Kconfig.platforms | 1 +
> > > 1 file changed, 1 insertion(+)
> > >
> > > diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
> > > index 21074f6..b241290 100644
> > > --- a/arch/arm64/Kconfig.platforms
> > > +++ b/arch/arm64/Kconfig.platforms
> > > @@ -133,6 +133,7 @@ config ARCH_VEXPRESS
> > >
> > > config ARCH_XGENE
> > > bool "AppliedMicro X-Gene SOC Family"
> > > + depends on !ARM64_16K_PAGES
> > > help
> > > This enables support for AppliedMicro X-Gene SOC Family
> >
> > This would be the case on Juno as well. But maybe at some point the
> > X-Gene family would gain a CPU with such support.
> >
> > Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
> > harder to enable. We've had a few questions recently about enabling it
> > on CPUs that don't have such feature.
>
> I thought there was also a suggestion that we could fail gracefully in
> the EFI stub if we detected an unsupported page size?
Yup. There are other things we could/should test, too.
I believe Jeremy had a patch, but due to churn in that area it didn't
get picked up.
Mark.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 11:20 ` Mark Rutland
@ 2016-01-28 14:50 ` Jeremy Linton
0 siblings, 0 replies; 9+ messages in thread
From: Jeremy Linton @ 2016-01-28 14:50 UTC (permalink / raw)
To: linux-arm-kernel
On 01/28/2016 05:20 AM, Mark Rutland wrote:
> On Thu, Jan 28, 2016 at 11:08:20AM +0000, Will Deacon wrote:
>> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
>> I thought there was also a suggestion that we could fail gracefully in
>> the EFI stub if we detected an unsupported page size?
>
> Yup. There are other things we could/should test, too.
>
> I believe Jeremy had a patch, but due to churn in that area it didn't
> get picked up.
I will clean-up and re-post that patch in the future too. It was fairly
trivial so if someone feels the need for immediately...
https://lkml.org/lkml/2015/10/14/948
IMHO, The main sticking point initially was that the correct place for
the check was a moving target. That problem has been fixed, so it should
be easy to move it.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 11:08 ` Will Deacon
2016-01-28 11:20 ` Mark Rutland
@ 2016-01-28 11:27 ` Suzuki K. Poulose
2016-01-28 11:30 ` Ard Biesheuvel
1 sibling, 1 reply; 9+ messages in thread
From: Suzuki K. Poulose @ 2016-01-28 11:27 UTC (permalink / raw)
To: linux-arm-kernel
On 28/01/16 11:08, Will Deacon wrote:
> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
>> On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
>>> 16K page size is an optional feature of the architecture, and is not
>>> supported by the X-Gene SoC family.
This enables support for AppliedMicro X-Gene SOC Family
>>
>> This would be the case on Juno as well. But maybe at some point the
>> X-Gene family would gain a CPU with such support.
>>
>> Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
>> harder to enable. We've had a few questions recently about enabling it
>> on CPUs that don't have such feature.
>
> I thought there was also a suggestion that we could fail gracefully in
> the EFI stub if we detected an unsupported page size?
Yes, there was. But then it was also recommended [1] to add a new stubbed function
for both arm & arm64, where it got lost. May be we should revive it.
https://lkml.org/lkml/2015/10/15/489
Thanks
Suzuki
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 11:27 ` Suzuki K. Poulose
@ 2016-01-28 11:30 ` Ard Biesheuvel
2016-01-28 11:34 ` Suzuki K. Poulose
0 siblings, 1 reply; 9+ messages in thread
From: Ard Biesheuvel @ 2016-01-28 11:30 UTC (permalink / raw)
To: linux-arm-kernel
On 28 January 2016 at 12:27, Suzuki K. Poulose <Suzuki.Poulose@arm.com> wrote:
> On 28/01/16 11:08, Will Deacon wrote:
>>
>> On Thu, Jan 28, 2016 at 10:34:41AM +0000, Catalin Marinas wrote:
>>>
>>> On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
>>>>
>>>> 16K page size is an optional feature of the architecture, and is not
>>>> supported by the X-Gene SoC family.
>
>
> This enables support for AppliedMicro X-Gene SOC Family
>>>
>>>
>>> This would be the case on Juno as well. But maybe at some point the
>>> X-Gene family would gain a CPU with such support.
>>>
>>> Anyway, I would rather make 16K pages depend on EXPERT, make it a bit
>>> harder to enable. We've had a few questions recently about enabling it
>>> on CPUs that don't have such feature.
>>
>>
>> I thought there was also a suggestion that we could fail gracefully in
>> the EFI stub if we detected an unsupported page size?
>
>
> Yes, there was. But then it was also recommended [1] to add a new stubbed
> function
> for both arm & arm64, where it got lost. May be we should revive it.
>
> https://lkml.org/lkml/2015/10/15/489
>
I can pick this up
--
Ard.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-28 11:30 ` Ard Biesheuvel
@ 2016-01-28 11:34 ` Suzuki K. Poulose
0 siblings, 0 replies; 9+ messages in thread
From: Suzuki K. Poulose @ 2016-01-28 11:34 UTC (permalink / raw)
To: linux-arm-kernel
On 28/01/16 11:30, Ard Biesheuvel wrote:
> On 28 January 2016 at 12:27, Suzuki K. Poulose <Suzuki.Poulose@arm.com> wrote:
>> On 28/01/16 11:08, Will Deacon wrote:
>>> I thought there was also a suggestion that we could fail gracefully in
>>> the EFI stub if we detected an unsupported page size?
>>
>>
>> Yes, there was. But then it was also recommended [1] to add a new stubbed
>> function
>> for both arm & arm64, where it got lost. May be we should revive it.
>>
>> https://lkml.org/lkml/2015/10/15/489
>>
>
> I can pick this up
>
Thanks Ard.
Cheers
Suzuki
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size
2016-01-27 23:10 [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size dann frazier
2016-01-28 10:34 ` Catalin Marinas
@ 2016-01-28 11:24 ` Mark Rutland
1 sibling, 0 replies; 9+ messages in thread
From: Mark Rutland @ 2016-01-28 11:24 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, Jan 27, 2016 at 04:10:30PM -0700, dann frazier wrote:
> 16K page size is an optional feature of the architecture,
Technically, support for any particular page size and endianness
configuration is an optional architectural feature.
I don't think we can capture this information for each SoC family or
specific SoC.
The best thing we can do is early checks in the EFI stub (and
potentially bootloaders) to check whether the kernel's configured page
size and endianness is implemented.
Thanks,
Mark.
> and is not supported by the X-Gene SoC family.
>
> Signed-off-by: dann frazier <dann.frazier@canonical.com>
> ---
> arch/arm64/Kconfig.platforms | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
> index 21074f6..b241290 100644
> --- a/arch/arm64/Kconfig.platforms
> +++ b/arch/arm64/Kconfig.platforms
> @@ -133,6 +133,7 @@ config ARCH_VEXPRESS
>
> config ARCH_XGENE
> bool "AppliedMicro X-Gene SOC Family"
> + depends on !ARM64_16K_PAGES
> help
> This enables support for AppliedMicro X-Gene SOC Family
>
> --
> 2.7.0
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2016-01-28 14:50 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-01-27 23:10 [PATCH] arm64: Disallow combination of ARCH_XGENE and 16K page size dann frazier
2016-01-28 10:34 ` Catalin Marinas
2016-01-28 11:08 ` Will Deacon
2016-01-28 11:20 ` Mark Rutland
2016-01-28 14:50 ` Jeremy Linton
2016-01-28 11:27 ` Suzuki K. Poulose
2016-01-28 11:30 ` Ard Biesheuvel
2016-01-28 11:34 ` Suzuki K. Poulose
2016-01-28 11:24 ` Mark Rutland
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