From: Niklas Schnelle > Sent: 15 April 2021 13:37 > > Instead of relying on the fallback in asm-generic/io.h which sets > PCI_IOBASE 0 if it is not defined set it explicitly. > > Link: https://lore.kernel.org/lkml/CAK8P3a3PK9zyeP4ymELtc2ZYnymECoACiigw9Za+pvSJpCk5=g@xxxxxxxxxxxxxx/ > Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx> > --- > arch/sparc/include/asm/io.h | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/arch/sparc/include/asm/io.h b/arch/sparc/include/asm/io.h > index 2eefa526b38f..100992ba1317 100644 > --- a/arch/sparc/include/asm/io.h > +++ b/arch/sparc/include/asm/io.h > @@ -1,6 +1,10 @@ > /* SPDX-License-Identifier: GPL-2.0 */ > #ifndef ___ASM_SPARC_IO_H > #define ___ASM_SPARC_IO_H > + > +/* On LEON I/O Space is accessed through low iomem */ > +#define PCI_IOBASE ((void __iomem *)0) > + > #if defined(__sparc__) && defined(__arch64__) > #include <asm/io_64.h> > #else > -- > 2.25.1 Not sure the comment is informative enough. Maybe something like: /* * On LEON PCI addresses below 64k are converted to IO accesses. * io_remap_xxx() (whatever is it called) returns a kernel virtual * address in the PCI window so inb() doesn't need to add an offset. */ That'll save the next person doing a lot of digging. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)