On Wed, 2019-01-23 at 16:28 +0000, Honnappa Nagarahalli wrote: > > On Fri, 2019-01-18 at 05:50 +0000, Honnappa Nagarahalli wrote: > > > > > > > > > > Hi, > > > > > > > > > > > > > > > > > > > > The cacheline size (RTE_CACHE_LINE_SIZE) for ARM > > > > > > > > > > CPUs is > > > > > > > > > > set to be 128B by default. Mellanox's BlueField is > > > > > > > > > > an > > > > > > > > > > ARM CPU having > > > > > > > > > > Cortex-A72 > > > > > > > > > > and its CL size is 64B. > > > > > > > > Just wondering how many devices are out there with 128B > > > > > > > > cache line? I also have not heard about any future > > > > > > > > devices > > > > > > > > with 128B cache line. If the majority is 64B, why not > > > > > > > > keep > > > > > > > > 64B as the default? > > > > > > > > > > > > > > The problem is, In the armv8 spec the cache line size is > > > > > > > IMPLEMENTATION DEFINED. Marvell's embedded processors has > > 128B > > > > CL > > > > > > > and Server processors has 64B CL. > > > > > > > > > > > > > > Assuming the defconfig_arm64-armv8a-linuxapp-gcc will be > > > > > > > used > > > > > > > by distro folks then that configuration should support > > > > > > > all the > > > > > > > devices with > > > > > > > armv8.1 spec. For instance, marvells new chips are > > > > > > > armv8.2 but > > > > > > > we can not make that as default. > > > > > > What will happen in the future when we will have v9, v10 > > > > > > etc? I > > > > > > think the distro(generic/binary portable) config should get > > > > > > rid > > > > > > of v8. > > > > > > > > > > Will it be too much overhead if the image is same for v8, v9 > > > > > and > > > > > v10. > > > > > I think, we can inline with what distro folks are doing for > > > > > other > > > > > packages, I think, DPDK package does not need any exception. > > > > Yes, we need to be inline with any other package. My > > > > understanding > > > > is that the image will be same for v8,v9,v10 (any input from > > > > distro > > > > engineers will help here). So, my question is, should the > > > > config > > > > file/name used by distros contain anything specific to armv8? > > > Jerin, after following [1], I am not unable to understand when > > > the > > > file config/arm/arm64_armv8_linuxapp_gcc gets used. Is this file > > > required? > > > > If I understand it correctly, only for cross compiling on x86. > > distro folks build the generic image on arm64 with > > -Dmachine=default for > > arm64. > I thought for cross compilation we have target specific config files > in config/arm. For ex: arm64_dpaa2_linuxapp_gcc, > arm64_thunderx_linuxapp_gcc
Yes. config/arm/arm64_armv8_linuxapp_gcc will be used for cross compile arm64 image, equivalent to config/defconfig_arm64-armv8a-linuxapp-gcc in cross compiling domain for meson. > > > > > > 1. http://mails.dpdk.org/archives/dev/2019-January/123272.html
