On Wed, Oct 4, 2023 at 5:21 PM Jisheng Zhang <jszhang@xxxxxxxxxx> wrote: > Drew found "CONFIG_DMA_GLOBAL_POOL=y causes ADMA buffer alloc to fail" > the log looks like: > [ 3.741083] mmc0: Unable to allocate ADMA buffers - falling back to standard DMA > > The logic is: generic riscv defconfig selects ARCH_RENESAS then > ARCH_R9A07G043 which selects DMA_GLOBAL_POOL, which assumes all > non-dma-coherent riscv platforms have a dma global pool, this assumption > seems not correct. And I believe DMA_GLOBAL_POOL should not be > selected by ARCH_SOCFAMILIY, instead, only ARCH under some specific > conditions can select it globaly, for example NOMMU ARM and so on, > because it's designed for special cases such as "nommu cases where > non-cacheable memory lives in a fixed place in the physical address > map" as pointed out by Robin. > > Fix the issue by making ARCH_R9A07G043 (riscv version) depend on > NONPORTABLE, thus generic defconfig won't select ARCH_R9A07G043 by > default. And even for random config case, there will be less debug > effort once we see NONPORTABLE is enabled. > > Reported-by: Drew Fustini <dfustini@xxxxxxxxxxxx> > Closes: https://lore.kernel.org/linux-riscv/ZRuamJuShOnvP1pr@x1/ > Fixes: 484861e09f3e ("soc: renesas: Kconfig: Select the required configs for RZ/Five SoC") > Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx> Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> I guess this is the right thing to do until a better solution is found. I.e. will queue in renesas-fixes for v6.6. 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
