Re: [PATCH 1/5] ARM: wire up HWCAP2 feature bits to the CPU modalias

2017-01-04 Thread Ard Biesheuvel 
On 2 January 2017 at 23:40, Russell King - ARM Linux
 wrote:
> On Mon, Jan 02, 2017 at 09:06:04PM +, Ard Biesheuvel wrote:
>> On 31 October 2016 at 16:13, Russell King - ARM Linux
>>  wrote:
>> > On Sat, Oct 29, 2016 at 11:08:36AM +0100, Ard Biesheuvel wrote:
>> >> On 18 October 2016 at 11:52, Ard Biesheuvel  
>> >> wrote:
>> >> > Wire up the generic support for exposing CPU feature bits via the
>> >> > modalias in /sys/device/system/cpu. This allows udev to automatically
>> >> > load modules for things like crypto algorithms that are implemented
>> >> > using optional instructions.
>> >> >
>> >> > Signed-off-by: Ard Biesheuvel 
>> >> > ---
>> >> >  arch/arm/Kconfig  |  1 +
>> >> >  arch/arm/include/asm/cpufeature.h | 32 
>> >> >  2 files changed, 33 insertions(+)
>> >> >
>> >>
>> >> Russell,
>> >>
>> >> do you have any concerns regarding this patch? If not, I will drop it
>> >> into the patch system.
>> >
>> > It's still something I need to look at... I've been offline last week,
>> > and sort-of offline the previous week, so I'm catching up.
>> >
>>
>> Hi Russell,
>>
>> Any thoughts yet?
>
> None, and the patch is well buried now that it'll take me a while to
> find... back in mid-October?  Yea, I'll have to drop everything and
> go digging through my mailboxes to find it... and I'm just catching
> up (again) after a week and a bit's time offline - yep, it's wonderful
> timing.  Sorry, no time to look at it right now, you're not the only
> one wanting my attention at the moment.
>

No worries. It is not exactly urgent, but it is a useful enhancement
nonetheless.

> Please try again in about a week's time - don't leave it a few months,
> and please include the patch.
>

OK
--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 1/5] ARM: wire up HWCAP2 feature bits to the CPU modalias

2017-01-02 Thread Russell King - ARM Linux 
On Mon, Jan 02, 2017 at 09:06:04PM +, Ard Biesheuvel wrote:
> On 31 October 2016 at 16:13, Russell King - ARM Linux
>  wrote:
> > On Sat, Oct 29, 2016 at 11:08:36AM +0100, Ard Biesheuvel wrote:
> >> On 18 October 2016 at 11:52, Ard Biesheuvel  
> >> wrote:
> >> > Wire up the generic support for exposing CPU feature bits via the
> >> > modalias in /sys/device/system/cpu. This allows udev to automatically
> >> > load modules for things like crypto algorithms that are implemented
> >> > using optional instructions.
> >> >
> >> > Signed-off-by: Ard Biesheuvel 
> >> > ---
> >> >  arch/arm/Kconfig  |  1 +
> >> >  arch/arm/include/asm/cpufeature.h | 32 
> >> >  2 files changed, 33 insertions(+)
> >> >
> >>
> >> Russell,
> >>
> >> do you have any concerns regarding this patch? If not, I will drop it
> >> into the patch system.
> >
> > It's still something I need to look at... I've been offline last week,
> > and sort-of offline the previous week, so I'm catching up.
> >
> 
> Hi Russell,
> 
> Any thoughts yet?

None, and the patch is well buried now that it'll take me a while to
find... back in mid-October?  Yea, I'll have to drop everything and
go digging through my mailboxes to find it... and I'm just catching
up (again) after a week and a bit's time offline - yep, it's wonderful
timing.  Sorry, no time to look at it right now, you're not the only
one wanting my attention at the moment.

Please try again in about a week's time - don't leave it a few months,
and please include the patch.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.
--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 1/5] ARM: wire up HWCAP2 feature bits to the CPU modalias

2017-01-02 Thread Ard Biesheuvel 
On 31 October 2016 at 16:13, Russell King - ARM Linux
 wrote:
> On Sat, Oct 29, 2016 at 11:08:36AM +0100, Ard Biesheuvel wrote:
>> On 18 October 2016 at 11:52, Ard Biesheuvel  
>> wrote:
>> > Wire up the generic support for exposing CPU feature bits via the
>> > modalias in /sys/device/system/cpu. This allows udev to automatically
>> > load modules for things like crypto algorithms that are implemented
>> > using optional instructions.
>> >
>> > Signed-off-by: Ard Biesheuvel 
>> > ---
>> >  arch/arm/Kconfig  |  1 +
>> >  arch/arm/include/asm/cpufeature.h | 32 
>> >  2 files changed, 33 insertions(+)
>> >
>>
>> Russell,
>>
>> do you have any concerns regarding this patch? If not, I will drop it
>> into the patch system.
>
> It's still something I need to look at... I've been offline last week,
> and sort-of offline the previous week, so I'm catching up.
>

Hi Russell,

Any thoughts yet?

Thanks,
Ard.
--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 1/5] ARM: wire up HWCAP2 feature bits to the CPU modalias

2016-10-31 Thread Russell King - ARM Linux 
On Sat, Oct 29, 2016 at 11:08:36AM +0100, Ard Biesheuvel wrote:
> On 18 October 2016 at 11:52, Ard Biesheuvel  wrote:
> > Wire up the generic support for exposing CPU feature bits via the
> > modalias in /sys/device/system/cpu. This allows udev to automatically
> > load modules for things like crypto algorithms that are implemented
> > using optional instructions.
> >
> > Signed-off-by: Ard Biesheuvel 
> > ---
> >  arch/arm/Kconfig  |  1 +
> >  arch/arm/include/asm/cpufeature.h | 32 
> >  2 files changed, 33 insertions(+)
> >
> 
> Russell,
> 
> do you have any concerns regarding this patch? If not, I will drop it
> into the patch system.

It's still something I need to look at... I've been offline last week,
and sort-of offline the previous week, so I'm catching up.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.
--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 1/5] ARM: wire up HWCAP2 feature bits to the CPU modalias

2016-10-29 Thread Ard Biesheuvel 
On 18 October 2016 at 11:52, Ard Biesheuvel  wrote:
> Wire up the generic support for exposing CPU feature bits via the
> modalias in /sys/device/system/cpu. This allows udev to automatically
> load modules for things like crypto algorithms that are implemented
> using optional instructions.
>
> Signed-off-by: Ard Biesheuvel 
> ---
>  arch/arm/Kconfig  |  1 +
>  arch/arm/include/asm/cpufeature.h | 32 
>  2 files changed, 33 insertions(+)
>

Russell,

do you have any concerns regarding this patch? If not, I will drop it
into the patch system.

Herbert,

I will resend the followup patches in this series to linux-crypto@
once this prerequisite is in place

Thanks,
Ard.


> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index b5d529fdffab..1a0c6a486a9c 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -21,6 +21,7 @@ config ARM
> select GENERIC_ALLOCATOR
> select GENERIC_ATOMIC64 if (CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI)
> select GENERIC_CLOCKEVENTS_BROADCAST if SMP
> +   select GENERIC_CPU_AUTOPROBE
> select GENERIC_EARLY_IOREMAP
> select GENERIC_IDLE_POLL_SETUP
> select GENERIC_IRQ_PROBE
> diff --git a/arch/arm/include/asm/cpufeature.h 
> b/arch/arm/include/asm/cpufeature.h
> new file mode 100644
> index ..19c3901a
> --- /dev/null
> +++ b/arch/arm/include/asm/cpufeature.h
> @@ -0,0 +1,32 @@
> +/*
> + * Copyright (C) 2016 Linaro Ltd. 
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#ifndef __ASM_CPUFEATURE_H
> +#define __ASM_CPUFEATURE_H
> +
> +#include 
> +
> +/*
> + * Due to the fact that ELF_HWCAP is a 32-bit type on ARM, and given the 
> number
> + * of optional CPU features it defines, ARM's CPU capability bits have been
> + * divided across separate elf_hwcap and elf_hwcap2 variables, each of which
> + * covers a subset of the available CPU features.
> + *
> + * Currently, only a few of those are suitable for automatic module loading
> + * (which is the primary use case of this facility) and those happen to be 
> all
> + * covered by HWCAP2. So let's only expose those via the CPU modalias for 
> now.
> + */
> +#define MAX_CPU_FEATURES   (8 * sizeof(elf_hwcap2))
> +#define cpu_feature(x) ilog2(HWCAP2_ ## x)
> +
> +static inline bool cpu_have_feature(unsigned int num)
> +{
> +   return elf_hwcap2 & (1UL << num);
> +}
> +
> +#endif
> --
> 2.7.4
>
--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH 1/5] ARM: wire up HWCAP2 feature bits to the CPU modalias

2016-10-18 Thread Ard Biesheuvel 
Wire up the generic support for exposing CPU feature bits via the
modalias in /sys/device/system/cpu. This allows udev to automatically
load modules for things like crypto algorithms that are implemented
using optional instructions.

Signed-off-by: Ard Biesheuvel 
---
 arch/arm/Kconfig  |  1 +
 arch/arm/include/asm/cpufeature.h | 32 
 2 files changed, 33 insertions(+)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index b5d529fdffab..1a0c6a486a9c 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -21,6 +21,7 @@ config ARM
select GENERIC_ALLOCATOR
select GENERIC_ATOMIC64 if (CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI)
select GENERIC_CLOCKEVENTS_BROADCAST if SMP
+   select GENERIC_CPU_AUTOPROBE
select GENERIC_EARLY_IOREMAP
select GENERIC_IDLE_POLL_SETUP
select GENERIC_IRQ_PROBE
diff --git a/arch/arm/include/asm/cpufeature.h 
b/arch/arm/include/asm/cpufeature.h
new file mode 100644
index ..19c3901a
--- /dev/null
+++ b/arch/arm/include/asm/cpufeature.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2016 Linaro Ltd. 
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __ASM_CPUFEATURE_H
+#define __ASM_CPUFEATURE_H
+
+#include 
+
+/*
+ * Due to the fact that ELF_HWCAP is a 32-bit type on ARM, and given the number
+ * of optional CPU features it defines, ARM's CPU capability bits have been
+ * divided across separate elf_hwcap and elf_hwcap2 variables, each of which
+ * covers a subset of the available CPU features.
+ *
+ * Currently, only a few of those are suitable for automatic module loading
+ * (which is the primary use case of this facility) and those happen to be all
+ * covered by HWCAP2. So let's only expose those via the CPU modalias for now.
+ */
+#define MAX_CPU_FEATURES   (8 * sizeof(elf_hwcap2))
+#define cpu_feature(x) ilog2(HWCAP2_ ## x)
+
+static inline bool cpu_have_feature(unsigned int num)
+{
+   return elf_hwcap2 & (1UL << num);
+}
+
+#endif
-- 
2.7.4

--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html