Hi, This discussion is specific to the SuperH port, therefore please avoid mailing [email protected], which targets all ports. I have already adjusted the address in Cc: to [email protected].
Thanks Aurelien On 2025-12-31 02:04, Rob Landley wrote: > On 11/24/25 01:18, Philippe Mathieu-Daudé wrote: > > On 1/9/25 09:47, Geert Uytterhoeven wrote: > > > > > On Sun, 24 Aug 2025 at 20:40, Rob Landley <[email protected]> wrote: > > > > Anyway, this works fine on little endian, but the qemu-system-sh4eb > > > > build has something hinky in the ethernet, I haven't tackled it myself > > > > because I don't know whether the device emulation or the driver is > > > > what's missing an endian swap. (I don't want to fix it the "wrong way", > > > > > > That is using sh_eth, right? > > > > > > Last time I tried booting a big-endian ARM kernel on R-Car M2-W, > > > the Linux kernel booted fine, except for Ethernet. So sh_eth is > > > definitely > > > not big-endian clean. > > > > qemu-system-sh4{eb} only emulates the R2D+ board, which AFAIK > > provides ethernet via a RTL8139 over PCI. While old, RTL8139 > > is very tested and expected to have endianness well handled. > > Expected, sure. In reality? Compare the sh4 vs sh4eb tarballs in > https://landley.net/bin/mkroot/0.8.13/ (in each case extract and > ./run-qemu.sh should get you a shell prompt). > > The sh4 one has working ethernet, the sh4eb one always reports link down and > it doesn't seem to probe the mac address right. Built from almost the same > configs, the only difference is: > > https://github.com/landley/toybox/blob/0.8.13/mkroot/mkroot.sh#L297 > > Line 305 adds: > [ "$CROSS" == sh4eb ] && KCONF+=,CPU_BIG_ENDIAN > > When I tried to track it down, I didn't know if the kernel or qemu was what > had it backwards, so it went back on the todo heap and composted... > > > > [*] I didn't have a big-endian userspace. > > That script builds one, the resulting binary tarball is at > https://landley.net/bin/mkroot/0.8.13/sh2eb.tgz and the toolchain I used is > at > https://landley.net/bin/toolchains/25-03-2024/sh4eb-linux-musl-cross.tar.xz > which was built with https://landley.net/toybox/faq.html#cross2 > > There might also be something wrong with -hda block device support, I'd have > to check my notes. But I can work around lack of -hda with nbd-server, kinda > hard to do it the other way... > > Rob > > -- Aurelien Jarno GPG: 4096R/1DDD8C9B [email protected] http://aurel32.net
