From mboxrd@z Thu Jan 1 00:00:00 1970 From: gregory.clement@free-electrons.com (Gregory CLEMENT) Date: Mon, 24 Nov 2014 20:01:43 +0100 Subject: [PATCH] ARM: PJ4: allow building in Thumb-2 mode In-Reply-To: References: <1416830200-11114-1-git-send-email-ard.biesheuvel@linaro.org> <2078609.NLHB18YoOo@wuerfel> <4653047.WBmUTsHC57@wuerfel> <54736CB9.1090307@free-electrons.com> Message-ID: <54738097.4020208@free-electrons.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 24/11/2014 18:48, Ard Biesheuvel wrote: > On 24 November 2014 at 18:36, Gregory CLEMENT > wrote: >> Hi Arnd, >> >> On 24/11/2014 18:17, Arnd Bergmann wrote: >>> On Monday 24 November 2014 16:34:47 Ard Biesheuvel wrote: >>>> On 24 November 2014 at 16:29, Arnd Bergmann wrote: >>>>> On Monday 24 November 2014 12:56:40 Ard Biesheuvel wrote: >>>>>> Two files that get included when building the multi_v7_defconfig target >>>>>> fail to build when selecting THUMB2_KERNEL for this configuration. >>>>>> >>>>>> In both cases, we can just build the file as ARM code, as none of its >>>>>> symbols are exported to modules, so there are no interworking concerns. >>>>>> In the iwmmxt.S case, add ENDPROC() declarations so the symbols are >>>>>> annotated as functions, resulting in the linker to emit the appropriate >>>>>> mode switches. >>>>>> >>>>>> Signed-off-by: Ard Biesheuvel >>>>> >>>>> Ah, very nice. I tried this before, but my version didn't actually >>>>> work, presumably because I didn't know about the ENDPROC() stuff. >>>>> >>>>> Have you tested this on a machine that has IWMMXT enabled? >>>>> >>>> >>>> No, I don't have access to such a machine, unfortunately. >>> >>> Adding a few mvebu folks to Cc, maybe one of them can test your patch. >> >> Actually even it is a feature of the PJ4 machine non of the mvebu machines >> currently use it. I only see this configuration enabled for the pxa family. >> So I think you would have more feedback with the pxa maintainers/owners. >> > > Are you saying PJ4 should be dropped from 'default' here? Not at all. I didn't find it in the configuration file, but I didn't realized it was because of this "default y". Sorry for the noise. > > config IWMMXT > bool "Enable iWMMXt support" > depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B > default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B > -- Gregory Clement, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com