From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Tue, 12 Jan 2010 17:17:33 +0000 Subject: question about ARM11MP cpu architecture identification In-Reply-To: References: <1263313572.29654.105.camel@pc1117.cambridge.arm.com> <20100112164220.GJ27771@n2100.arm.linux.org.uk> <1263315302.29654.110.camel@pc1117.cambridge.arm.com> Message-ID: <20100112171733.GC5633@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Jan 12, 2010 at 07:03:35PM +0200, saeed bishara wrote: > On Tue, Jan 12, 2010 at 6:55 PM, 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). > > > 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).