On Monday 23 November 2015 12:38:47 Stephen Boyd wrote: > On 11/23, Arnd Bergmann wrote: > > On Monday 23 November 2015 09:14:39 Christopher Covington wrote: > > > On 11/23/2015 03:15 AM, Arnd Bergmann wrote: > > > LPAE is only supported in the Krait 450. > > > > > > http://www.anandtech.com/show/7537/qualcomms-snapdragon-805-25ghz-128bit-memory-interface-d3d11class-graphics-more > > > > > > I'm pretty sure idiv support came earlier, but I don't have the > > > specifics on hand. > > > > I have seen that article, but didn't trust it as a canonical > > source of information here. > > > > If you can confirm that it's right, that would mean that we > > don't support LPAE on mach-qcom, as the only SoC with Krait 450 > > seems to be APQ8084, and mainline Linux doesn't run on that. > > arch/arm/boot/dts/qcom-apq8084.dtsi exists in the mainline > kernel. We support more than what's in the Kconfig language > under mach-qcom. Ok, cool. I'm sometimes confused by the model numbers, could you do a separate patch to update the Kconfig help text? > And yes LPAE is supported by apq8084 (as is > IDIV). Here's the /proc/cpuinfo on that device. > # cat /proc/cpuinfo > processor : 0 > model name : ARMv7 Processor rev 1 (v7l) > BogoMIPS : 38.40 > Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm Ok. > > The ones we do support are MSM8x60 (Scorpion), MSM8960 > > (Krait-without-number),and MSM7874 (Krait 400). Do those all > > support IDIV but not LPAE? > > > > Krait supports IDIV for all versions. Scorpion doesn't support > IDIV or lpae. Here's the output of /proc/cpuinfo on that device. > > # cat /proc/cpuinfo > processor : 0 > model name : ARMv7 Processor rev 2 (v7l) > BogoMIPS : 13.50 > Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpd32 > CPU implementer : 0x51 > CPU architecture: 7 > CPU variant : 0x0 > CPU part : 0x02d > CPU revision : 2 Ok, that leaves just one missing puzzle piece: can you confirm that no supported Krait variant other than Krait 450 / apq8084 has LPAE? Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html