diff mbox

[v4,1/4] arm64: arch_timer: Add device tree binding for A-008585 erratum

Message ID 1467877572-10817-1-git-send-email-oss@buserror.net (mailing list archive)
State New, archived
Headers show

Commit Message

Crystal Wood July 7, 2016, 7:46 a.m. UTC
This erratum describes a bug in logic outside the core, so MIDR can't be
used to identify its presence, and reading an SoC-specific revision
register from common arch timer code would be awkward.  So, describe it
in the device tree.

Signed-off-by: Scott Wood <oss@buserror.net>
Acked-by: Rob Herring <robh@kernel.org>
---
 Documentation/devicetree/bindings/arm/arch_timer.txt | 6 ++++++
 1 file changed, 6 insertions(+)

Comments

Matthias Brugger Aug. 25, 2016, 11:04 a.m. UTC | #1
Hi all,

On 07/07/16 09:46, Scott Wood wrote:
> This erratum describes a bug in logic outside the core, so MIDR can't be
> used to identify its presence, and reading an SoC-specific revision
> register from common arch timer code would be awkward.  So, describe it
> in the device tree.
>
> Signed-off-by: Scott Wood <oss@buserror.net>
> Acked-by: Rob Herring <robh@kernel.org>
> ---

As of today I wasn't able to find this series in linux-next. Was this 
series somehow forgotten? Scott maybe you can resend the patches adding 
the clocksource maintainer.

Regards,
Matthias
Ding Tianhong Sept. 8, 2016, 11:46 a.m. UTC | #2
Ping

On 2016/8/25 19:04, Matthias Brugger wrote:
> Hi all,
> 
> On 07/07/16 09:46, Scott Wood wrote:
>> This erratum describes a bug in logic outside the core, so MIDR can't be
>> used to identify its presence, and reading an SoC-specific revision
>> register from common arch timer code would be awkward.  So, describe it
>> in the device tree.
>>
>> Signed-off-by: Scott Wood <oss@buserror.net>
>> Acked-by: Rob Herring <robh@kernel.org>
>> ---
> 
> As of today I wasn't able to find this series in linux-next. Was this series somehow forgotten? Scott maybe you can resend the patches adding the clocksource maintainer.
> 
> Regards,
> Matthias
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> 
>
Marc Zyngier Sept. 8, 2016, 12:07 p.m. UTC | #3
On 08/09/16 12:46, Ding Tianhong wrote:
> Ping

Oh please! Maybe you could look at the couple of points I've raised in
this thread and help addressing them, given that you have a vested
interest in seeing these patches being merged? Pinging people this way
is not very productive.

Thanks,

	M.

> 
> On 2016/8/25 19:04, Matthias Brugger wrote:
>> Hi all,
>>
>> On 07/07/16 09:46, Scott Wood wrote:
>>> This erratum describes a bug in logic outside the core, so MIDR can't be
>>> used to identify its presence, and reading an SoC-specific revision
>>> register from common arch timer code would be awkward.  So, describe it
>>> in the device tree.
>>>
>>> Signed-off-by: Scott Wood <oss@buserror.net>
>>> Acked-by: Rob Herring <robh@kernel.org>
>>> ---
>>
>> As of today I wasn't able to find this series in linux-next. Was this series somehow forgotten? Scott maybe you can resend the patches adding the clocksource maintainer.
>>
>> Regards,
>> Matthias
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>>
>>
> 
>
Ding Tianhong Sept. 8, 2016, 12:31 p.m. UTC | #4
On 2016/9/8 20:07, Marc Zyngier wrote:
> On 08/09/16 12:46, Ding Tianhong wrote:
>> Ping
> 
> Oh please! Maybe you could look at the couple of points I've raised in
> this thread and help addressing them, given that you have a vested
> interest in seeing these patches being merged? Pinging people this way
> is not very productive.
> 
> Thanks,
> 

Ok, I miss that patch, I will review your command and feedback, thanks.

Ding

> 	M.
> 
>>
>> On 2016/8/25 19:04, Matthias Brugger wrote:
>>> Hi all,
>>>
>>> On 07/07/16 09:46, Scott Wood wrote:
>>>> This erratum describes a bug in logic outside the core, so MIDR can't be
>>>> used to identify its presence, and reading an SoC-specific revision
>>>> register from common arch timer code would be awkward.  So, describe it
>>>> in the device tree.
>>>>
>>>> Signed-off-by: Scott Wood <oss@buserror.net>
>>>> Acked-by: Rob Herring <robh@kernel.org>
>>>> ---
>>>
>>> As of today I wasn't able to find this series in linux-next. Was this series somehow forgotten? Scott maybe you can resend the patches adding the clocksource maintainer.
>>>
>>> Regards,
>>> Matthias
>>>
>>> _______________________________________________
>>> linux-arm-kernel mailing list
>>> linux-arm-kernel@lists.infradead.org
>>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>>>
>>>
>>
>>
> 
>
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/arm/arch_timer.txt b/Documentation/devicetree/bindings/arm/arch_timer.txt
index e774128..ef5fbe9 100644
--- a/Documentation/devicetree/bindings/arm/arch_timer.txt
+++ b/Documentation/devicetree/bindings/arm/arch_timer.txt
@@ -25,6 +25,12 @@  to deliver its interrupts via SPIs.
 - always-on : a boolean property. If present, the timer is powered through an
   always-on power domain, therefore it never loses context.
 
+- fsl,erratum-a008585 : A boolean property. Indicates the presence of
+  QorIQ erratum A-008585, which says that reading the counter is
+  unreliable unless the same value is returned by back-to-back reads.
+  This also affects writes to the tval register, due to the implicit
+  counter read.
+
 ** Optional properties:
 
 - arm,cpu-registers-not-fw-configured : Firmware does not initialize