On Fri, Oct 9, 2020 at 5:54 PM Karol Herbst <kherbst@xxxxxxxxxx> wrote: > > On Fri, Oct 9, 2020 at 11:35 PM Ondrej Zary <linux@xxxxxxx> wrote: > > > > Hello, > > I'm testing 5.9.0-rc8 and found that Riva TNT2 stopped working: > > [ 0.000000] Linux version 5.9.0-rc8+ (zary@gsql) (gcc (Debian 8.3.0-6) 8.3.0, GNU ld (GNU Binutils for Debian) 2.31.1) #326 SMP Fri Oct 9 22:31:40 CEST 2020 > > ... > > [ 14.771464] nouveau 0000:01:00.0: GPU not supported on big-endian > > [ 14.771782] nouveau: probe of 0000:01:00.0 failed with error -38 > > > > big-endian? WTF? The machine is x86. > > > > mhh, we reworked the endianess checks a bit and apparently that broke > something... I will give it some thoughts, but could you be so kind > and create an mmiotrace under 5.9 with nouveau? You won't need to > start X or anything while doing it. Just enable the trace and modprobe > nouveau and collect the trace. Looks like nvkm_device_endianness unconditionally reads out 0x4. I don't think that reg is there pre-NV11. At least NV4, NV5, NV10 and maybe NV15 (which is logically pre-NV11) don't support big-endian mode. Not sure about NV1A, which was the IGP of the series and IIRC logically pre-NV11 as well (but clearly could only be used with x86 chips, since it was part of the motherboard). Aha, it's documented in rnndb: https://github.com/envytools/envytools/blob/master/rnndb/bus/pmc.xml <reg32 offset="0x004" name="ENDIAN" variants="NV1A-"/> -ilia _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
