* Catalin Marinas <catalin.marinas@xxxxxxx> [100317 11:04]: > On Wed, 2010-03-17 at 17:57 +0000, Tony Lindgren wrote: > > Here's an updated version of this patch with more details. > > > > Looks like VFPv3 is only available on V7: > > > > http://www.arm.com/products/processors/technologies/vector-floating-point.php > > But does it cause any problem if the feature is enabled in the kernel? > The vfp_init() code should check for its presence and set the hwcap > accordingly. Yeah, it causes the problem posted in the patch description. I took a quick look at it and at least the VFPFMRX in vfpmacros.h for CONFIG_VFPv3 is a problem. Also I think we would need to have separate vfp_get_double functions in vfphw.S for VFPv2 and 3 that get used based on the features. > Ideally, we should fix the VFP handling code to cope with dynamic > detection. I agree, being able to boot the same kernel and avoiding tens of recompiles to test something is a major time saver :) > > HAS_TLS reg is only on ARM11 starting with r1p0: > > > > http://infocenter.arm.com/help/topic/com.arm.doc.ddi0211k/Babeihid.html > > > > So that explains why it won't work on omap2420 as it's r0p2. > > Same here, would it work with dynamic detection? Hmm I believe here the problem is __switch_to in entry-armv.S. I don't think we want to dynamically test it every time.. Or at least it would have to be optimized out in most cases. > I would like to get v6+v7 support working fine together on RealView > boards as well (though not much spare time) but without disabling the > features that are present on v7 if they can be detected at run-time. I totally agree with you there. Regards, Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
