Messages in this thread | | | Date | Mon, 3 Jun 2019 14:26:08 +0200 | From | Angelo Dureghello <> | Subject | Re: [PATCH] m68k: io: Fix io{read,write}{16,32}be() for Coldfire peripherals |
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Hi Greg (and all),
couldn't seen any follow up on this patch. I tested it and at least for mcf5441x it works properly and solves all issues.
Do you think it may be accepted as an initial fix ?
Regards, Angelo
On Mon, Apr 29, 2019 at 10:19:37AM +0200, Geert Uytterhoeven wrote: > The generic definitions of mmio_{read,write}{16,32}be() in lib/iomap.c > assume that the {read,write}[wl]() I/O accessors always use little > endian accesses, and swap the result. > > However, the Coldfire versions of the {read,write}[wl]() I/O accessors are > special, in that they use native big endian instead of little endian for > accesses to the on-SoC peripheral block, thus violating the assumption. > > Fix this by providing our own variants, using the raw accessors, > reinstating the old behavior. This is fine on m68k, as no special > barriers are needed, and also avoids swapping data twice. > > Reported-by: Angelo Dureghello <angelo@sysam.it> > Fixes: aecc787c06f4300f ("iomap: Use non-raw io functions for io{read|write}XXbe") > Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> > --- > This can be reverted later, after this oddity of the Coldfire I/O > support has been fixed, and drivers have been updated. > --- > arch/m68k/include/asm/io.h | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/m68k/include/asm/io.h b/arch/m68k/include/asm/io.h > index aabe6420ead2a599..d47e7384681ab1cd 100644 > --- a/arch/m68k/include/asm/io.h > +++ b/arch/m68k/include/asm/io.h > @@ -8,6 +8,12 @@ > #include <asm/io_mm.h> > #endif > > +#define mmio_read16be(addr) __raw_readw(addr) > +#define mmio_read32be(addr) __raw_readl(addr) > + > +#define mmio_write16be(val, port) __raw_writew((val), (port)) > +#define mmio_write32be(val, port) __raw_writel((val), (port)) > + > #include <asm-generic/io.h> > > #endif /* _M68K_IO_H */ > -- > 2.17.1 >
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