[PATCH 2/2] ARM: l2c: Maintain CPU endianness for early resume function

[PATCH 2/2] ARM: l2c: Maintain CPU endianness for early resume function

[Dmitry Osipenko]

In big endian CPU mode l2x0_saved_regs structure stores registers values in BE
format. In order to maintain BE CPU mode, these values and immediate constants
must be converted back to LE format before writing them to cache controller.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 arch/arm/mm/l2c-l2x0-resume.S | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm/mm/l2c-l2x0-resume.S b/arch/arm/mm/l2c-l2x0-resume.S
index fda415e..9f99c7e 100644
--- a/arch/arm/mm/l2c-l2x0-resume.S
+++ b/arch/arm/mm/l2c-l2x0-resume.S
@@ -30,6 +30,15 @@ ENTRY(l2c310_early_resume)
 	teq	r1, #0
 	reteq	lr
 
+	@ Reverse for big endian kernel
+ARM_BE8(rev	r2, r2)
+ARM_BE8(rev	r3, r3)
+ARM_BE8(rev	r4, r4)
+ARM_BE8(rev	r5, r5)
+ARM_BE8(rev	r6, r6)
+ARM_BE8(rev	r7, r7)
+ARM_BE8(rev	r8, r8)
+
 	@ The prefetch and power control registers are revision dependent
 	@ and can be written whether or not the L2 cache is enabled
 	ldr	r0, [r1, #L2X0_CACHE_ID]
@@ -51,6 +60,7 @@ ENTRY(l2c310_early_resume)
 
 	str	r2, [r1, #L2X0_AUX_CTRL]
 	mov	r9, #L2X0_CTRL_EN
+ARM_BE8(rev	r9, r9)
 	str	r9, [r1, #L2X0_CTRL]
 	ret	lr
 ENDPROC(l2c310_early_resume)
-- 
2.2.1

Re: [PATCH 2/2] ARM: l2c: Maintain CPU endianness for early resume function

[Thierry Reding]

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On Tue, Jan 20, 2015 at 03:36:55PM +0300, Dmitry Osipenko wrote:
> In big endian CPU mode l2x0_saved_regs structure stores registers values in BE
> format. In order to maintain BE CPU mode, these values and immediate constants
> must be converted back to LE format before writing them to cache controller.
> 
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
>  arch/arm/mm/l2c-l2x0-resume.S | 10 ++++++++++
>  1 file changed, 10 insertions(+)

Hi Russell,

Did you get a chance yet to review this patch? It's a dependency for
enabling big-endian support on Tegra. As such, I wonder if you would be
willing to ack it, so that I can take it through the Tegra tree along
with the rest of the patches.

If you prefer to take it through the ARM tree, that's fine, too. In that
case would you be able to provide a stable branch that I can merge into
the Tegra tree to resolve the dependency?

Thanks,
Thierry

> diff --git a/arch/arm/mm/l2c-l2x0-resume.S b/arch/arm/mm/l2c-l2x0-resume.S
> index fda415e..9f99c7e 100644
> --- a/arch/arm/mm/l2c-l2x0-resume.S
> +++ b/arch/arm/mm/l2c-l2x0-resume.S
> @@ -30,6 +30,15 @@ ENTRY(l2c310_early_resume)
>  	teq	r1, #0
>  	reteq	lr
>  
> +	@ Reverse for big endian kernel
> +ARM_BE8(rev	r2, r2)
> +ARM_BE8(rev	r3, r3)
> +ARM_BE8(rev	r4, r4)
> +ARM_BE8(rev	r5, r5)
> +ARM_BE8(rev	r6, r6)
> +ARM_BE8(rev	r7, r7)
> +ARM_BE8(rev	r8, r8)
> +
>  	@ The prefetch and power control registers are revision dependent
>  	@ and can be written whether or not the L2 cache is enabled
>  	ldr	r0, [r1, #L2X0_CACHE_ID]
> @@ -51,6 +60,7 @@ ENTRY(l2c310_early_resume)
>  
>  	str	r2, [r1, #L2X0_AUX_CTRL]
>  	mov	r9, #L2X0_CTRL_EN
> +ARM_BE8(rev	r9, r9)
>  	str	r9, [r1, #L2X0_CTRL]
>  	ret	lr
>  ENDPROC(l2c310_early_resume)
> -- 
> 2.2.1
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

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Re: [PATCH 2/2] ARM: l2c: Maintain CPU endianness for early resume function

[Russell King - ARM Linux]

On Wed, Mar 11, 2015 at 11:18:46AM +0100, Thierry Reding wrote:
> On Tue, Jan 20, 2015 at 03:36:55PM +0300, Dmitry Osipenko wrote:
> > In big endian CPU mode l2x0_saved_regs structure stores registers values in BE
> > format. In order to maintain BE CPU mode, these values and immediate constants
> > must be converted back to LE format before writing them to cache controller.
> > 
> > Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> > ---
> >  arch/arm/mm/l2c-l2x0-resume.S | 10 ++++++++++
> >  1 file changed, 10 insertions(+)
> 
> Hi Russell,
> 
> Did you get a chance yet to review this patch? It's a dependency for
> enabling big-endian support on Tegra. As such, I wonder if you would be
> willing to ack it, so that I can take it through the Tegra tree along
> with the rest of the patches.

Yes, it's fallen through the cracks.

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>

Thanks.

-- 
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according to speedtest.net.

Re: [PATCH 2/2] ARM: l2c: Maintain CPU endianness for early resume function

[Dmitry Osipenko]

11.03.2015 13:18, Thierry Reding пишет:
> On Tue, Jan 20, 2015 at 03:36:55PM +0300, Dmitry Osipenko wrote:
>> In big endian CPU mode l2x0_saved_regs structure stores registers values in BE
>> format. In order to maintain BE CPU mode, these values and immediate constants
>> must be converted back to LE format before writing them to cache controller.
>>
>> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
>> ---
>>   arch/arm/mm/l2c-l2x0-resume.S | 10 ++++++++++
>>   1 file changed, 10 insertions(+)
>
> Hi Russell,
>
> Did you get a chance yet to review this patch? It's a dependency for
> enabling big-endian support on Tegra. As such, I wonder if you would be
> willing to ack it, so that I can take it through the Tegra tree along
> with the rest of the patches.
>
> If you prefer to take it through the ARM tree, that's fine, too. In that
> case would you be able to provide a stable branch that I can merge into
> the Tegra tree to resolve the dependency?
>
> Thanks,
> Thierry
>
>> diff --git a/arch/arm/mm/l2c-l2x0-resume.S b/arch/arm/mm/l2c-l2x0-resume.S
>> index fda415e..9f99c7e 100644
>> --- a/arch/arm/mm/l2c-l2x0-resume.S
>> +++ b/arch/arm/mm/l2c-l2x0-resume.S
>> @@ -30,6 +30,15 @@ ENTRY(l2c310_early_resume)
>>   	teq	r1, #0
>>   	reteq	lr
>>
>> +	@ Reverse for big endian kernel
>> +ARM_BE8(rev	r2, r2)
>> +ARM_BE8(rev	r3, r3)
>> +ARM_BE8(rev	r4, r4)
>> +ARM_BE8(rev	r5, r5)
>> +ARM_BE8(rev	r6, r6)
>> +ARM_BE8(rev	r7, r7)
>> +ARM_BE8(rev	r8, r8)
>> +
>>   	@ The prefetch and power control registers are revision dependent
>>   	@ and can be written whether or not the L2 cache is enabled
>>   	ldr	r0, [r1, #L2X0_CACHE_ID]
>> @@ -51,6 +60,7 @@ ENTRY(l2c310_early_resume)
>>
>>   	str	r2, [r1, #L2X0_AUX_CTRL]
>>   	mov	r9, #L2X0_CTRL_EN
>> +ARM_BE8(rev	r9, r9)
>>   	str	r9, [r1, #L2X0_CTRL]
>>   	ret	lr
>>   ENDPROC(l2c310_early_resume)
>> --
>> 2.2.1
>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

This patch missed register reverse for "ldr". Please hold it, I'll send v3.

-- 
Dmitry