question about ARM11MP cpu architecture identification

question about ARM11MP cpu architecture identification

[saeed bishara]

Hi,
    The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
will identify it as ARMv7, and if the kernel was configured with
CPU_V7 only, then the lookup_processor_type() function also will
identify it as ARMv7. Am I missing something here?

saeed

question about ARM11MP cpu architecture identification

[Catalin Marinas]

On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
>     The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
> the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
> the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
> will identify it as ARMv7, and if the kernel was configured with
> CPU_V7 only, then the lookup_processor_type() function also will
> identify it as ARMv7. Am I missing something here?

cpu_architecture() returns the architecture version of the supported MMU
which on ARM11MPCore is the same as on ARMv7.

Even if it is possible to configure both v6 and v7 in the same kernel, I
don't think it is currently possible to successfully run such kernel.

-- 
Catalin

question about ARM11MP cpu architecture identification

[Russell King - ARM Linux]

On Tue, Jan 12, 2010 at 06:21:50PM +0200, saeed bishara wrote:
> Hi,
>     The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
> the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
> the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
> will identify it as ARMv7, and if the kernel was configured with
> CPU_V7 only, then the lookup_processor_type() function also will
> identify it as ARMv7. Am I missing something here?

Welcome to the wonderful world of *unprintable*.  The age of being
able to reliably tell what type of CPU you are running on has sadly
well and truely passed into history.

I'm afraid it's now a hit-and-miss affair.

question about ARM11MP cpu architecture identification

[Russell King - ARM Linux]

On Tue, Jan 12, 2010 at 04:26:12PM +0000, Catalin Marinas wrote:
> On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
> >     The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
> > the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
> > the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
> > will identify it as ARMv7, and if the kernel was configured with
> > CPU_V7 only, then the lookup_processor_type() function also will
> > identify it as ARMv7. Am I missing something here?
> 
> cpu_architecture() returns the architecture version of the supported MMU
> which on ARM11MPCore is the same as on ARMv7.
> 
> Even if it is possible to configure both v6 and v7 in the same kernel, I
> don't think it is currently possible to successfully run such kernel.

What makes you think that?  I've been building v6+v7 kernels for Realview
(with a patch to provide the right build options for the ARMv7 arch/arm/mm
files) and ISTR it works fine on my Realview board.

question about ARM11MP cpu architecture identification

[saeed bishara]

On Tue, Jan 12, 2010 at 6:26 PM, Catalin Marinas
<catalin.marinas@arm.com> wrote:
> On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
>> ? ? The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
>> the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
>> the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
>> will identify it as ARMv7, and if the kernel was configured with
>> CPU_V7 only, then the lookup_processor_type() function also will
>> identify it as ARMv7. Am I missing something here?
>
> cpu_architecture() returns the architecture version of the supported MMU
> which on ARM11MPCore is the same as on ARMv7.
but this function used by do_alignment and doesn't seem to be related
to MMU type!
>
> Even if it is possible to configure both v6 and v7 in the same kernel, I
> don't think it is currently possible to successfully run such kernel.
>
> --
> Catalin
>
>

question about ARM11MP cpu architecture identification

[Catalin Marinas]

On Tue, 2010-01-12 at 16:42 +0000, Russell King - ARM Linux wrote:
> On Tue, Jan 12, 2010 at 04:26:12PM +0000, Catalin Marinas wrote:
> > On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
> > >     The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
> > > the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
> > > the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
> > > will identify it as ARMv7, and if the kernel was configured with
> > > CPU_V7 only, then the lookup_processor_type() function also will
> > > identify it as ARMv7. Am I missing something here?
> >
> > cpu_architecture() returns the architecture version of the supported MMU
> > which on ARM11MPCore is the same as on ARMv7.
> >
> > Even if it is possible to configure both v6 and v7 in the same kernel, I
> > don't think it is currently possible to successfully run such kernel.
> 
> What makes you think that?  I've been building v6+v7 kernels for Realview
> (with a patch to provide the right build options for the ARMv7 arch/arm/mm
> files) and ISTR it works fine on my Realview board.

I don't remember exactly but it didn't work for me some time ago. I
think it failed to build (though I could have worked around this with
something like -march=all).

If you have a clean patch, please push it upstream.

-- 
Catalin

question about ARM11MP cpu architecture identification

[saeed bishara]

On Tue, Jan 12, 2010 at 6:55 PM, Catalin Marinas
<catalin.marinas@arm.com> wrote:
> On Tue, 2010-01-12 at 16:42 +0000, Russell King - ARM Linux wrote:
>> On Tue, Jan 12, 2010 at 04:26:12PM +0000, Catalin Marinas wrote:
>> > On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
>> > > ? ? The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
>> > > the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
>> > > the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
>> > > will identify it as ARMv7, and if the kernel was configured with
>> > > CPU_V7 only, then the lookup_processor_type() function also will
>> > > identify it as ARMv7. Am I missing something here?
>> >
>> > cpu_architecture() returns the architecture version of the supported MMU
>> > which on ARM11MPCore is the same as on ARMv7.
>> >
>> > Even if it is possible to configure both v6 and v7 in the same kernel, I
>> > don't think it is currently possible to successfully run such kernel.
>>
>> What makes you think that? ?I've been building v6+v7 kernels for Realview
>> (with a patch to provide the right build options for the ARMv7 arch/arm/mm
>> files) and ISTR it works fine on my Realview board.
>
> I don't remember exactly but it didn't work for me some time ago. I
> think it failed to build (though I could have worked around this with
> something like -march=all).
>
I think you need the attached patch from Lennert (it was planned to be
sent later by me)

saeed
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question about ARM11MP cpu architecture identification

[Russell King - ARM Linux]

On Tue, Jan 12, 2010 at 04:55:01PM +0000, Catalin Marinas wrote:
> On Tue, 2010-01-12 at 16:42 +0000, Russell King - ARM Linux wrote:
> > On Tue, Jan 12, 2010 at 04:26:12PM +0000, Catalin Marinas wrote:
> > > On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
> > > >     The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
> > > > the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
> > > > the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
> > > > will identify it as ARMv7, and if the kernel was configured with
> > > > CPU_V7 only, then the lookup_processor_type() function also will
> > > > identify it as ARMv7. Am I missing something here?
> > >
> > > cpu_architecture() returns the architecture version of the supported MMU
> > > which on ARM11MPCore is the same as on ARMv7.
> > >
> > > Even if it is possible to configure both v6 and v7 in the same kernel, I
> > > don't think it is currently possible to successfully run such kernel.
> > 
> > What makes you think that?  I've been building v6+v7 kernels for Realview
> > (with a patch to provide the right build options for the ARMv7 arch/arm/mm
> > files) and ISTR it works fine on my Realview board.
> 
> I don't remember exactly but it didn't work for me some time ago. I
> think it failed to build (though I could have worked around this with
> something like -march=all).
> 
> If you have a clean patch, please push it upstream.

This is what I use, as part of my patches for running the kernel on the
model.  I have a similar patch for ARMv6 as well.

diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile
index 055cb2a..35b889c 100644
--- a/arch/arm/mm/Makefile
+++ b/arch/arm/mm/Makefile
@@ -39,6 +39,8 @@ obj-$(CONFIG_CPU_CACHE_V6)	+= cache-v6.o
 obj-$(CONFIG_CPU_CACHE_V7)	+= cache-v7.o
 obj-$(CONFIG_CPU_CACHE_FA)	+= cache-fa.o
 
+AFLAGS_cache-v7.o	:=-march=armv7-a
+
 obj-$(CONFIG_CPU_COPY_V3)	+= copypage-v3.o
 obj-$(CONFIG_CPU_COPY_V4WT)	+= copypage-v4wt.o
 obj-$(CONFIG_CPU_COPY_V4WB)	+= copypage-v4wb.o
@@ -58,6 +60,8 @@ obj-$(CONFIG_CPU_TLB_V6)	+= tlb-v6.o
 obj-$(CONFIG_CPU_TLB_V7)	+= tlb-v7.o
 obj-$(CONFIG_CPU_TLB_FA)	+= tlb-fa.o
 
+AFLAGS_tlb-v7.o		:=-march=armv7-a
+
 obj-$(CONFIG_CPU_ARM610)	+= proc-arm6_7.o
 obj-$(CONFIG_CPU_ARM710)	+= proc-arm6_7.o
 obj-$(CONFIG_CPU_ARM7TDMI)	+= proc-arm7tdmi.o
@@ -84,6 +88,8 @@ obj-$(CONFIG_CPU_FEROCEON)	+= proc-feroceon.o
 obj-$(CONFIG_CPU_V6)		+= proc-v6.o
 obj-$(CONFIG_CPU_V7)		+= proc-v7.o
 
+AFLAGS_proc-v7.o	:=-march=armv7-a
+
 obj-$(CONFIG_CACHE_FEROCEON_L2)	+= cache-feroceon-l2.o
 obj-$(CONFIG_CACHE_L2X0)	+= cache-l2x0.o
 obj-$(CONFIG_CACHE_XSC3L2)	+= cache-xsc3l2.o

question about ARM11MP cpu architecture identification

[Russell King - ARM Linux]

On Tue, Jan 12, 2010 at 07:03:35PM +0200, saeed bishara wrote:
> On Tue, Jan 12, 2010 at 6:55 PM, Catalin Marinas
> <catalin.marinas@arm.com> wrote:
> > On Tue, 2010-01-12 at 16:42 +0000, Russell King - ARM Linux wrote:
> >> On Tue, Jan 12, 2010 at 04:26:12PM +0000, Catalin Marinas wrote:
> >> > On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
> >> > > ? ? The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
> >> > > the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
> >> > > the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
> >> > > will identify it as ARMv7, and if the kernel was configured with
> >> > > CPU_V7 only, then the lookup_processor_type() function also will
> >> > > identify it as ARMv7. Am I missing something here?
> >> >
> >> > cpu_architecture() returns the architecture version of the supported MMU
> >> > which on ARM11MPCore is the same as on ARMv7.
> >> >
> >> > Even if it is possible to configure both v6 and v7 in the same kernel, I
> >> > don't think it is currently possible to successfully run such kernel.
> >>
> >> What makes you think that? ?I've been building v6+v7 kernels for Realview
> >> (with a patch to provide the right build options for the ARMv7 arch/arm/mm
> >> files) and ISTR it works fine on my Realview board.
> >
> > I don't remember exactly but it didn't work for me some time ago. I
> > think it failed to build (though I could have worked around this with
> > something like -march=all).
> >
> I think you need the attached patch from Lennert (it was planned to be
> sent later by me)

Using -Wa,-march= for assembler options is actually a better idea.
I'll update my patch with that (which actually reflects what I did
for Integrator/CP with ARM926 + v6).

question about ARM11MP cpu architecture identification

[Russell King - ARM Linux]

On Tue, Jan 12, 2010 at 05:17:33PM +0000, Russell King - ARM Linux wrote:
> On Tue, Jan 12, 2010 at 07:03:35PM +0200, saeed bishara wrote:
> > On Tue, Jan 12, 2010 at 6:55 PM, Catalin Marinas
> > <catalin.marinas@arm.com> wrote:
> > > On Tue, 2010-01-12 at 16:42 +0000, Russell King - ARM Linux wrote:
> > >> On Tue, Jan 12, 2010 at 04:26:12PM +0000, Catalin Marinas wrote:
> > >> > On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
> > >> > > ? ? The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
> > >> > > the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
> > >> > > the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
> > >> > > will identify it as ARMv7, and if the kernel was configured with
> > >> > > CPU_V7 only, then the lookup_processor_type() function also will
> > >> > > identify it as ARMv7. Am I missing something here?
> > >> >
> > >> > cpu_architecture() returns the architecture version of the supported MMU
> > >> > which on ARM11MPCore is the same as on ARMv7.
> > >> >
> > >> > Even if it is possible to configure both v6 and v7 in the same kernel, I
> > >> > don't think it is currently possible to successfully run such kernel.
> > >>
> > >> What makes you think that? ?I've been building v6+v7 kernels for Realview
> > >> (with a patch to provide the right build options for the ARMv7 arch/arm/mm
> > >> files) and ISTR it works fine on my Realview board.
> > >
> > > I don't remember exactly but it didn't work for me some time ago. I
> > > think it failed to build (though I could have worked around this with
> > > something like -march=all).
> > >
> > I think you need the attached patch from Lennert (it was planned to be
> > sent later by me)
> 
> Using -Wa,-march= for assembler options is actually a better idea.
> I'll update my patch with that (which actually reflects what I did
> for Integrator/CP with ARM926 + v6).

Ok, here's the combined patch.  Ack?

 arch/arm/mm/Makefile |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile
index 827e238..e8d34a8 100644
--- a/arch/arm/mm/Makefile
+++ b/arch/arm/mm/Makefile
@@ -27,6 +27,9 @@ obj-$(CONFIG_CPU_ABRT_EV5TJ)	+= abort-ev5tj.o
 obj-$(CONFIG_CPU_ABRT_EV6)	+= abort-ev6.o
 obj-$(CONFIG_CPU_ABRT_EV7)	+= abort-ev7.o
 
+AFLAGS_abort-ev6.o	:=-Wa,-march=armv6k
+AFLAGS_abort-ev7.o	:=-Wa,-march=armv7-a
+
 obj-$(CONFIG_CPU_PABRT_LEGACY)	+= pabort-legacy.o
 obj-$(CONFIG_CPU_PABRT_V6)	+= pabort-v6.o
 obj-$(CONFIG_CPU_PABRT_V7)	+= pabort-v7.o
@@ -39,6 +42,9 @@ obj-$(CONFIG_CPU_CACHE_V6)	+= cache-v6.o
 obj-$(CONFIG_CPU_CACHE_V7)	+= cache-v7.o
 obj-$(CONFIG_CPU_CACHE_FA)	+= cache-fa.o
 
+AFLAGS_cache-v6.o	:=-Wa,-march=armv6
+AFLAGS_cache-v7.o	:=-Wa,-march=armv7-a
+
 obj-$(CONFIG_CPU_COPY_V3)	+= copypage-v3.o
 obj-$(CONFIG_CPU_COPY_V4WT)	+= copypage-v4wt.o
 obj-$(CONFIG_CPU_COPY_V4WB)	+= copypage-v4wb.o
@@ -58,6 +64,9 @@ obj-$(CONFIG_CPU_TLB_V6)	+= tlb-v6.o
 obj-$(CONFIG_CPU_TLB_V7)	+= tlb-v7.o
 obj-$(CONFIG_CPU_TLB_FA)	+= tlb-fa.o
 
+AFLAGS_tlb-v6.o		:=-Wa,-march=armv6
+AFLAGS_tlb-v7.o		:=-Wa,-march=armv7-a
+
 obj-$(CONFIG_CPU_ARM610)	+= proc-arm6_7.o
 obj-$(CONFIG_CPU_ARM710)	+= proc-arm6_7.o
 obj-$(CONFIG_CPU_ARM7TDMI)	+= proc-arm7tdmi.o
@@ -84,6 +93,9 @@ obj-$(CONFIG_CPU_FEROCEON)	+= proc-feroceon.o
 obj-$(CONFIG_CPU_V6)		+= proc-v6.o
 obj-$(CONFIG_CPU_V7)		+= proc-v7.o
 
+AFLAGS_proc-v6.o	:=-Wa,-march=armv6
+AFLAGS_proc-v7.o	:=-Wa,-march=armv7-a
+
 obj-$(CONFIG_CACHE_FEROCEON_L2)	+= cache-feroceon-l2.o
 obj-$(CONFIG_CACHE_L2X0)	+= cache-l2x0.o
 obj-$(CONFIG_CACHE_XSC3L2)	+= cache-xsc3l2.o

question about ARM11MP cpu architecture identification

[Catalin Marinas]

On Tue, 2010-01-12 at 17:24 +0000, Russell King - ARM Linux wrote:
> On Tue, Jan 12, 2010 at 05:17:33PM +0000, Russell King - ARM Linux wrote:
> > On Tue, Jan 12, 2010 at 07:03:35PM +0200, saeed bishara wrote:
> > > On Tue, Jan 12, 2010 at 6:55 PM, Catalin Marinas
> > > <catalin.marinas@arm.com> wrote:
> > > > On Tue, 2010-01-12 at 16:42 +0000, Russell King - ARM Linux wrote:
> > > >> On Tue, Jan 12, 2010 at 04:26:12PM +0000, Catalin Marinas wrote:
> > > >> > On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
> > > >> > >     The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
> > > >> > > the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
> > > >> > > the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
> > > >> > > will identify it as ARMv7, and if the kernel was configured with
> > > >> > > CPU_V7 only, then the lookup_processor_type() function also will
> > > >> > > identify it as ARMv7. Am I missing something here?
> > > >> >
> > > >> > cpu_architecture() returns the architecture version of the supported MMU
> > > >> > which on ARM11MPCore is the same as on ARMv7.
> > > >> >
> > > >> > Even if it is possible to configure both v6 and v7 in the same kernel, I
> > > >> > don't think it is currently possible to successfully run such kernel.
> > > >>
> > > >> What makes you think that?  I've been building v6+v7 kernels for Realview
> > > >> (with a patch to provide the right build options for the ARMv7 arch/arm/mm
> > > >> files) and ISTR it works fine on my Realview board.
> > > >
> > > > I don't remember exactly but it didn't work for me some time ago. I
> > > > think it failed to build (though I could have worked around this with
> > > > something like -march=all).
> > > >
> > > I think you need the attached patch from Lennert (it was planned to be
> > > sent later by me)
> >
> > Using -Wa,-march= for assembler options is actually a better idea.
> > I'll update my patch with that (which actually reflects what I did
> > for Integrator/CP with ARM926 + v6).
> 
> Ok, here's the combined patch.  Ack?

Looks fine to me. Thanks.

-- 
Catalin

question about ARM11MP cpu architecture identification

[Nicolas Pitre]

On Tue, 12 Jan 2010, Russell King - ARM Linux wrote:

> On Tue, Jan 12, 2010 at 05:17:33PM +0000, Russell King - ARM Linux wrote:
> > On Tue, Jan 12, 2010 at 07:03:35PM +0200, saeed bishara wrote:
> > > On Tue, Jan 12, 2010 at 6:55 PM, Catalin Marinas
> > > <catalin.marinas@arm.com> wrote:
> > > > On Tue, 2010-01-12 at 16:42 +0000, Russell King - ARM Linux wrote:
> > > >> On Tue, Jan 12, 2010 at 04:26:12PM +0000, Catalin Marinas wrote:
> > > >> > On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
> > > >> > > ? ? The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
> > > >> > > the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
> > > >> > > the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
> > > >> > > will identify it as ARMv7, and if the kernel was configured with
> > > >> > > CPU_V7 only, then the lookup_processor_type() function also will
> > > >> > > identify it as ARMv7. Am I missing something here?
> > > >> >
> > > >> > cpu_architecture() returns the architecture version of the supported MMU
> > > >> > which on ARM11MPCore is the same as on ARMv7.
> > > >> >
> > > >> > Even if it is possible to configure both v6 and v7 in the same kernel, I
> > > >> > don't think it is currently possible to successfully run such kernel.
> > > >>
> > > >> What makes you think that? ?I've been building v6+v7 kernels for Realview
> > > >> (with a patch to provide the right build options for the ARMv7 arch/arm/mm
> > > >> files) and ISTR it works fine on my Realview board.
> > > >
> > > > I don't remember exactly but it didn't work for me some time ago. I
> > > > think it failed to build (though I could have worked around this with
> > > > something like -march=all).
> > > >
> > > I think you need the attached patch from Lennert (it was planned to be
> > > sent later by me)
> > 
> > Using -Wa,-march= for assembler options is actually a better idea.
> > I'll update my patch with that (which actually reflects what I did
> > for Integrator/CP with ARM926 + v6).
> 
> Ok, here's the combined patch.  Ack?

We need this as well so please consider adding it to your tree.

Acked-by: Nicolas Pitre <nico@marvell.com>


> 
>  arch/arm/mm/Makefile |   12 ++++++++++++
>  1 files changed, 12 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile
> index 827e238..e8d34a8 100644
> --- a/arch/arm/mm/Makefile
> +++ b/arch/arm/mm/Makefile
> @@ -27,6 +27,9 @@ obj-$(CONFIG_CPU_ABRT_EV5TJ)	+= abort-ev5tj.o
>  obj-$(CONFIG_CPU_ABRT_EV6)	+= abort-ev6.o
>  obj-$(CONFIG_CPU_ABRT_EV7)	+= abort-ev7.o
>  
> +AFLAGS_abort-ev6.o	:=-Wa,-march=armv6k
> +AFLAGS_abort-ev7.o	:=-Wa,-march=armv7-a
> +
>  obj-$(CONFIG_CPU_PABRT_LEGACY)	+= pabort-legacy.o
>  obj-$(CONFIG_CPU_PABRT_V6)	+= pabort-v6.o
>  obj-$(CONFIG_CPU_PABRT_V7)	+= pabort-v7.o
> @@ -39,6 +42,9 @@ obj-$(CONFIG_CPU_CACHE_V6)	+= cache-v6.o
>  obj-$(CONFIG_CPU_CACHE_V7)	+= cache-v7.o
>  obj-$(CONFIG_CPU_CACHE_FA)	+= cache-fa.o
>  
> +AFLAGS_cache-v6.o	:=-Wa,-march=armv6
> +AFLAGS_cache-v7.o	:=-Wa,-march=armv7-a
> +
>  obj-$(CONFIG_CPU_COPY_V3)	+= copypage-v3.o
>  obj-$(CONFIG_CPU_COPY_V4WT)	+= copypage-v4wt.o
>  obj-$(CONFIG_CPU_COPY_V4WB)	+= copypage-v4wb.o
> @@ -58,6 +64,9 @@ obj-$(CONFIG_CPU_TLB_V6)	+= tlb-v6.o
>  obj-$(CONFIG_CPU_TLB_V7)	+= tlb-v7.o
>  obj-$(CONFIG_CPU_TLB_FA)	+= tlb-fa.o
>  
> +AFLAGS_tlb-v6.o		:=-Wa,-march=armv6
> +AFLAGS_tlb-v7.o		:=-Wa,-march=armv7-a
> +
>  obj-$(CONFIG_CPU_ARM610)	+= proc-arm6_7.o
>  obj-$(CONFIG_CPU_ARM710)	+= proc-arm6_7.o
>  obj-$(CONFIG_CPU_ARM7TDMI)	+= proc-arm7tdmi.o
> @@ -84,6 +93,9 @@ obj-$(CONFIG_CPU_FEROCEON)	+= proc-feroceon.o
>  obj-$(CONFIG_CPU_V6)		+= proc-v6.o
>  obj-$(CONFIG_CPU_V7)		+= proc-v7.o
>  
> +AFLAGS_proc-v6.o	:=-Wa,-march=armv6
> +AFLAGS_proc-v7.o	:=-Wa,-march=armv7-a
> +
>  obj-$(CONFIG_CACHE_FEROCEON_L2)	+= cache-feroceon-l2.o
>  obj-$(CONFIG_CACHE_L2X0)	+= cache-l2x0.o
>  obj-$(CONFIG_CACHE_XSC3L2)	+= cache-xsc3l2.o
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> 

question about ARM11MP cpu architecture identification

[saeed bishara]

looks fine to me too.

On Tue, Jan 12, 2010 at 9:55 PM, Nicolas Pitre <nico@fluxnic.net> wrote:
> On Tue, 12 Jan 2010, Russell King - ARM Linux wrote:
>
>> On Tue, Jan 12, 2010 at 05:17:33PM +0000, Russell King - ARM Linux wrote:
>> > On Tue, Jan 12, 2010 at 07:03:35PM +0200, saeed bishara wrote:
>> > > On Tue, Jan 12, 2010 at 6:55 PM, Catalin Marinas
>> > > <catalin.marinas@arm.com> wrote:
>> > > > On Tue, 2010-01-12 at 16:42 +0000, Russell King - ARM Linux wrote:
>> > > >> On Tue, Jan 12, 2010 at 04:26:12PM +0000, Catalin Marinas wrote:
>> > > >> > On Tue, 2010-01-12 at 16:21 +0000, saeed bishara wrote:
>> > > >> > > ? ? The ARM11MP (rev r2p0) cpu architecture is ARMv6, and according to
>> > > >> > > the http://infocenter.arm.com, its Main ID register is 0x410FB024, and
>> > > >> > > the MMFR[3:0] is 3. but it looks to me that the cpu_architecture()
>> > > >> > > will identify it as ARMv7, and if the kernel was configured with
>> > > >> > > CPU_V7 only, then the lookup_processor_type() function also will
>> > > >> > > identify it as ARMv7. Am I missing something here?
>> > > >> >
>> > > >> > cpu_architecture() returns the architecture version of the supported MMU
>> > > >> > which on ARM11MPCore is the same as on ARMv7.
>> > > >> >
>> > > >> > Even if it is possible to configure both v6 and v7 in the same kernel, I
>> > > >> > don't think it is currently possible to successfully run such kernel.
>> > > >>
>> > > >> What makes you think that? ?I've been building v6+v7 kernels for Realview
>> > > >> (with a patch to provide the right build options for the ARMv7 arch/arm/mm
>> > > >> files) and ISTR it works fine on my Realview board.
>> > > >
>> > > > I don't remember exactly but it didn't work for me some time ago. I
>> > > > think it failed to build (though I could have worked around this with
>> > > > something like -march=all).
>> > > >
>> > > I think you need the attached patch from Lennert (it was planned to be
>> > > sent later by me)
>> >
>> > Using -Wa,-march= for assembler options is actually a better idea.
>> > I'll update my patch with that (which actually reflects what I did
>> > for Integrator/CP with ARM926 + v6).
>>
>> Ok, here's the combined patch. ?Ack?
>
> We need this as well so please consider adding it to your tree.
>
> Acked-by: Nicolas Pitre <nico@marvell.com>
>
>
>>
>> ?arch/arm/mm/Makefile | ? 12 ++++++++++++
>> ?1 files changed, 12 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile
>> index 827e238..e8d34a8 100644
>> --- a/arch/arm/mm/Makefile
>> +++ b/arch/arm/mm/Makefile
>> @@ -27,6 +27,9 @@ obj-$(CONFIG_CPU_ABRT_EV5TJ) ? ? ? ?+= abort-ev5tj.o
>> ?obj-$(CONFIG_CPU_ABRT_EV6) ? += abort-ev6.o
>> ?obj-$(CONFIG_CPU_ABRT_EV7) ? += abort-ev7.o
>>
>> +AFLAGS_abort-ev6.o ? :=-Wa,-march=armv6k
>> +AFLAGS_abort-ev7.o ? :=-Wa,-march=armv7-a
>> +
>> ?obj-$(CONFIG_CPU_PABRT_LEGACY) ? ? ? += pabort-legacy.o
>> ?obj-$(CONFIG_CPU_PABRT_V6) ? += pabort-v6.o
>> ?obj-$(CONFIG_CPU_PABRT_V7) ? += pabort-v7.o
>> @@ -39,6 +42,9 @@ obj-$(CONFIG_CPU_CACHE_V6) ?+= cache-v6.o
>> ?obj-$(CONFIG_CPU_CACHE_V7) ? += cache-v7.o
>> ?obj-$(CONFIG_CPU_CACHE_FA) ? += cache-fa.o
>>
>> +AFLAGS_cache-v6.o ? ?:=-Wa,-march=armv6
>> +AFLAGS_cache-v7.o ? ?:=-Wa,-march=armv7-a
>> +
>> ?obj-$(CONFIG_CPU_COPY_V3) ? ?+= copypage-v3.o
>> ?obj-$(CONFIG_CPU_COPY_V4WT) ?+= copypage-v4wt.o
>> ?obj-$(CONFIG_CPU_COPY_V4WB) ?+= copypage-v4wb.o
>> @@ -58,6 +64,9 @@ obj-$(CONFIG_CPU_TLB_V6) ? ?+= tlb-v6.o
>> ?obj-$(CONFIG_CPU_TLB_V7) ? ? += tlb-v7.o
>> ?obj-$(CONFIG_CPU_TLB_FA) ? ? += tlb-fa.o
>>
>> +AFLAGS_tlb-v6.o ? ? ? ? ? ? ?:=-Wa,-march=armv6
>> +AFLAGS_tlb-v7.o ? ? ? ? ? ? ?:=-Wa,-march=armv7-a
>> +
>> ?obj-$(CONFIG_CPU_ARM610) ? ? += proc-arm6_7.o
>> ?obj-$(CONFIG_CPU_ARM710) ? ? += proc-arm6_7.o
>> ?obj-$(CONFIG_CPU_ARM7TDMI) ? += proc-arm7tdmi.o
>> @@ -84,6 +93,9 @@ obj-$(CONFIG_CPU_FEROCEON) ?+= proc-feroceon.o
>> ?obj-$(CONFIG_CPU_V6) ? ? ? ? += proc-v6.o
>> ?obj-$(CONFIG_CPU_V7) ? ? ? ? += proc-v7.o
>>
>> +AFLAGS_proc-v6.o ? ? :=-Wa,-march=armv6
>> +AFLAGS_proc-v7.o ? ? :=-Wa,-march=armv7-a
>> +
>> ?obj-$(CONFIG_CACHE_FEROCEON_L2) ? ? ?+= cache-feroceon-l2.o
>> ?obj-$(CONFIG_CACHE_L2X0) ? ? += cache-l2x0.o
>> ?obj-$(CONFIG_CACHE_XSC3L2) ? += cache-xsc3l2.o
>>
>> _______________________________________________
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>> linux-arm-kernel at lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>>
>

question about ARM11MP cpu architecture identification

[Russell King - ARM Linux]

On Wed, Jan 13, 2010 at 01:27:43PM +0200, saeed bishara wrote:
> looks fine to me too.
> 
> On Tue, Jan 12, 2010 at 9:55 PM, Nicolas Pitre <nico@fluxnic.net> wrote:

You're both a little too late; it's already in Linus' tree.