On Fri, Feb 12, 2021 at 04:34:04PM -0600, Rob Herring wrote: > On Fri, Feb 12, 2021 at 3:01 PM Rob Herring <robh@xxxxxxxxxx> wrote: > > > > On Fri, Feb 12, 2021 at 9:17 AM Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > > > > > On Fri, Feb 12, 2021 at 08:16:04AM -0600, Rob Herring wrote: > > > > On Thu, Feb 11, 2021 at 9:31 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > > > > > > > > > Hi Rob, > > > > > > > > > > On Wed, Feb 03, 2021 at 03:26:03PM -0600, Rob Herring wrote: > > > > > > This adds the following commits from upstream: > > > > > > > > > > > > 183df9e9c2b9 gitignore: Ignore the swp files > > > > > > 0db6d09584e1 gitignore: Add cscope files > > > > > > 307afa1a7be8 Update Jon Loeliger's email > > > > > > ca16a723fa9d fdtdump: Fix gcc11 warning > > > > > > 64990a272e8f srcpos: increase MAX_SRCFILE_DEPTH > > > > > > 163f0469bf2e dtc: Allow overlays to have .dtbo extension > > > > > > 3b01518e688d Set last_comp_version correctly in new dtb and fix potential version issues in fdt_open_into > > > > > > f7e5737f26aa tests: Fix overlay_overlay_nosugar test case > > > > > > 7cd5d5fe43d5 libfdt: Tweak description of assume-aligned load helpers > > > > > > a7c404099349 libfdt: Internally perform potentially unaligned loads > > > > > > bab85e48a6f4 meson: increase default timeout for tests > > > > > > f8b46098824d meson: do not assume python is installed, skip tests > > > > > > 30a56bce4f0b meson: fix -Wall warning > > > > > > 5e735860c478 libfdt: Check for 8-byte address alignment in fdt_ro_probe_() > > > > > > 67849a327927 build-sys: add meson build > > > > > > 05874d08212d pylibfdt: allow build out of tree > > > > > > 3bc3a6b9fe0c dtc: Fix signedness comparisons warnings: Wrap (-1) > > > > > > e1147b159e92 dtc: Fix signedness comparisons warnings: change types > > > > > > 04cf1fdc0fcf convert-dtsv0: Fix signedness comparisons warning > > > > > > b30013edb878 libfdt: Fix kernel-doc comments > > > > > > > > > > > > Signed-off-by: Rob Herring <robh@xxxxxxxxxx> > > > > > > > > > > This patch causes my little-endian microblaze qemu emulations to fail > > > > > silently (no console output) in next-20210211. Reverting this patch > > > > > together with "scripts: dtc: Build fdtoverlay tool" fixes the problem. > > > > > > > > My guess would be something in libfdt. Maybe 7cd5d5fe43d5 or > > > > a7c404099349, though that should return to historical behavior. > > > > > > > > Can you give me the qemu command line and kernel cfg? > > > > > > > I copied everything you should need to build a kernel (including toolchain) > > > to http://server.roeck-us.net/qemu/microblazeel/ > > > > > > [ wow, I really need to update that compiler ] > > > > I can't seem to get BE/LE nor reverted or not working. It's always > > dying in microblaze_cache_init() based on the last print. It's your > > config, but gcc 10.1.0 off of kernel.org. > > It seems gcc 10.1 does not work. Seems to die before here: > > pcpu-alloc: s0 r0 d32768 u32768 alloc=1*32768 > > > There is at least one possible problem here that the FDT may only be 4 > > byte aligned. The assumption is 8 bytes to not have misaligned > > accesses (and only for 64-bit accesses if 4 byte aligned). That's an > > issue with the qemu image loading depending on the sizes and > > combination of images loaded. That doesn't explain your failure > > though. As the initrd is a multiple of 8 bytes, you should be fine. > > It's the built-in dtb alignment that is the problem. I had noticed > this earlier, then discovered I had no built-in DTB and QEMU provides > a default. And changing didn't help because on broken gcc-10 it was 8 > byte aligned. None of that should matter because we're not using the > built-in either, right? Wrong! The assembly entry code copies the > bootloader dtb into the built-in dtb space. I remember this now from > the last time I cleaned up the early DT code. I suppose the reason is > the bootloader dtb is not or may not be at an address mapped early. I think the problem is here: /* initialize device tree for usage in early_printk */ early_init_devtree(_fdt_start); That probably also explains why enabling earlycon doesn't help. > I'd really like to get rid of that copy. Anyway, the oneliner below > fixes it. We need it either way, but I'd like some comments on the > copy. > I can not comment on the copy, but the change below does indeed fix the problem. Feel free to add Tested-by: Guenter Roeck <linux@xxxxxxxxxxxx> to the patch if you send it out. Thanks, Guenter > Rob > > diff --git a/arch/microblaze/kernel/vmlinux.lds.S > b/arch/microblaze/kernel/vmlinux.lds.S > index df07b3d06cd6..fb31747ec092 100644 > --- a/arch/microblaze/kernel/vmlinux.lds.S > +++ b/arch/microblaze/kernel/vmlinux.lds.S > @@ -45,7 +45,7 @@ SECTIONS { > _etext = . ; > } > > - . = ALIGN (4) ; > + . = ALIGN (8) ; > __fdt_blob : AT(ADDR(__fdt_blob) - LOAD_OFFSET) { > _fdt_start = . ; /* place for fdt blob */ > *(__fdt_blob) ; /* Any link-placed DTB */
