Hi Jonas, On Fri, 2015-09-04 at 12:25 +0200, Jonas Gorski wrote: > Hi, > > On Thu, Sep 3, 2015 at 6:11 PM, Alexey Brodkin > <alexey.brod...@synopsys.com> wrote: > > Hi Jonas, > > > > On Thu, 2015-09-03 at 15:33 +0200, Jonas Gorski wrote: > > > Hi, > > > > > > On Wed, Sep 2, 2015 at 10:40 PM, Alexey Brodkin > > > <alexey.brod...@synopsys.com> wrote: > > > > Hi Jonas, > > > > > > > > On Wed, 2015-09-02 at 10:32 +0200, Jonas Gorski wrote: > > > > > Also please move > > > > > all common options from both subtargets into a > > > > > target/linux/arc/config-4.1. > > > > > > > > Well indeed there're same options in both configs. > > > > But please note nSIM and AXS10x are completely different boards. > > > > And each of those boards may have different CPU. > > > > > > > > This first set of patches only covers ARC legacy architecture (ARC 700). > > > > > > > > But with 4.2 release of Linux kernel new gen ARC architecture (ARC HS38) > > > > was introduced and once that patch set is accepted in OpenWRT I'll > > > > send another patch that add support of new gen ARC CPUs. > > > > > > > > My plan was to have following files structure: > > > > > > > > target/linux/arc/axs10x/profiles/arc700.mk > > > > /archs38.mk > > > > /nsim/profiles/arc700.mk > > > > /archs38.mk > > > > > > > > Is it acceptable or I need to modify it? > > > > > > That seems backward, since arc700 and hs38 are different > > > architectures, so I would assume their kernels and toolchains won't be > > > compatible. > > > > > > So I would use > > > > > > target/linuxarc/arc700 > > > and > > > target/linux/arc/hs38 > > > > > > and then > > > > > > target/linux/arc/profiles/axs10x.mk > > > and > > > target/linux/arc/profiles/nsim.mk > > > > > > (You can have "toplevel" profiles that apply to all subtargets) > > > > Well I don't understand how that will work. > > I mean we need to have different: > > [1] kernel config options for both pairs: boards (axs10x vs nsim) > > and architectures (arcv1 vs arcv2) > > [2] basefiles for boards (axs10x vs nsim) > > > > I.e. setting profiles for axs10x and nsim won't be enough. > > > > Maybe this all is not very clear, so I'll try to put here what we need to > > accommodate: > > [1] For axs10x board: > > a) base files for axs10x board > > b) kernel options for axs10x board > > c) kernel options for arc700 core in axs10x > > d) kernel options for archs38 core in axs10x > > > > [2] For nsim board: > > a) base files for nsim board > > b) kernel options for nsim board > > c) kernel options for arc700 > > core in nsim > > d) kernel options for archs38 core in nsim > > > > So maybe the only option that will work is having 2 top-level arc entries > > like: > > * target/linux/arcv1 (or arc700) > > * target/linux/arcv2 (or archs38) > > > > Or another alternative is 4 subtargets like that (I see something similar > > for RPi, > > see target/linux/brcm2708): > > brcm2708 does this because bcm2709 supports a newer arm instruction > set, so to not be limited by the older one we split it into 2708 and > 2709. If they both supported the same arm version, then there would be > no need for subtargets. > > > * target/linux/axs101 (which is axs10x with arc700) > > * target/linux/axs103 (which is axs10x with archs38) > > * target/linux/nsim_700 (which is nsim with arc700) > > * target/linux/nsim_hs (which is nsim with archs38) > > > > But that in its turn will require to duplicate basefiles and kernel configs > > relevant to boards but not cores. > > > > Any thoughts about that are much appreciated. > > Unfortunately that is not how OpenWrt is supposed to work. The > expectation is that a (sub)target is for all boards that share a > certain (family of) SoCs, not just a single board. Looking at Linux > 4.2, you are using device tree, so I would assume it would be possible > to build a kenrel that "supports" all boards with a arc700 cpu, > through passing the appropriate dtb to it. And likewise for the hs38. > If the bootloader does not support passing a dtb, then it maybe > appending a dtb like on ARM would be an option; or reserving space in > the kernel to patch in a dtb (we have a patch for MIPS for that, but > that would likely work similar for other targets). > > Having a subtarget for each board will create a huge burden for > release builds, es effectively we will then need to build a new > toolchain for each board, and they cannot share their packages feeds, > so we would also need to rebuild all packages for all boards. > > So please rework your target to not use/require per-board subtargets.
Sorry for another round of questions but from your answer I still don't understand what my source tree should look like? If one of my proposals above ok? For example this one? ------->8-------- * target/linux/arcv1 (or arc700) * target/linux/arcv2 (or archs38) ------->8-------- In this scheme we do have different architectures with incompatible tools and binaries. -Alexey _______________________________________________ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-devel
