Hi Wolfram, On Fri, Jun 18, 2021 at 11:57 AM Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> wrote: > > BTW, does it work (really) fine on R-Car Gen3? Mine does. > > Yes, mine does, too. So, I first wondered if the difference is an older > SCC variant. But when I let the timeouts run for a while, I get a DMA > problem. Which could also be the difference between Gen2 and Gen3 here: > > [ 53.328284] WARNING: CPU: 0 PID: 743 at kernel/dma/debug.c:498 add_dma_entry+0x158/0x180 > [ 53.336397] DMA-API: exceeded 7 overlapping mappings of cacheline 0x011807bc Someone's forgetting to clean up DMA mappings? Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds