Hi Marek, On Thu, Jan 7, 2021 at 11:36 AM Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> wrote: > On 04.01.2021 14:01, Geert Uytterhoeven wrote: > > Currently, the start address of physical memory is obtained by masking > > the program counter with a fixed mask of 0xf8000000. This mask value > > was chosen as a balance between the requirements of different platforms. > > However, this does require that the start address of physical memory is > > a multiple of 128 MiB, precluding booting Linux on platforms where this > > requirement is not fulfilled. > > > > Fix this limitation by validating the masked address against the memory > > information in the passed DTB. Only use the start address > > from DTB when masking would yield an out-of-range address, prefer the > > traditional method in all other cases. Note that this applies only to the > > explicitly passed DTB on modern systems, and not to a DTB appended to > > the kernel, or to ATAGS. The appended DTB may need to be augmented by > > information from ATAGS, which may need to rely on knowledge of the start > > address of physical memory itself. > > > > This allows to boot Linux on r7s9210/rza2mevb using the 64 MiB of SDRAM > > on the RZA2MEVB sub board, which is located at 0x0C000000 (CS3 space), > > i.e. not at a multiple of 128 MiB. > > > > Suggested-by: Nicolas Pitre <nico@xxxxxxxxxxx> > > Suggested-by: Ard Biesheuvel <ardb@xxxxxxxxxx> > > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> > > Reviewed-by: Ard Biesheuvel <ardb@xxxxxxxxxx> > > Acked-by: Nicolas Pitre <nico@xxxxxxxxxxx> > > I've checked all of my arm 32bit test systems and they still boot fine > with this patch. Feel free to add my: > > Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > > although I didn't test exactly the new features added by it. Thank you, regression-testing is very valuable! 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