On Fri, Mar 07, 2014 at 01:37:38AM +0100, Arnd Bergmann wrote:
On Thursday 06 March 2014, Russell King - ARM Linux wrote:
On Wed, Mar 05, 2014 at 11:49:08AM +0000, Liviu Dudau wrote:
The inline version of ioport_map() that gets used when !CONFIG_GENERIC_IOMAP is wrong. It returns a mapped (i.e. virtual) address that can start from zero and completely ignores the PCI_IOBASE and IO_SPACE_LIMIT that most architectures that use !CONFIG_GENERIC_MAP define.
What value does PCI_IOBASE and IO_SPACE_LIMIT have on other architectures who make use of asm-generic/io.h ?
$ git grep asm-generic/io.h arch/ arch/arc/include/asm/io.h:#include <asm-generic/io.h>
PCI support hasn't been upstreamed.
arch/blackfin/include/asm/io.h:#include <asm-generic/io.h> arch/metag/include/asm/io.h:#include <asm-generic/io.h>
No PCI support
arch/microblaze/include/asm/io.h:/* from asm-generic/io.h */
PCI_IOBASE=0, IO_SPACE_LIMIT=0xffffffff, so no change.
Seems to define _IO_BASE not PCI_IOBASE.
arch/openrisc/include/asm/io.h:#include <asm-generic/io.h>
No PCI support
arch/s390/include/asm/io.h:#include <asm-generic/io.h>
s390 supports PCI but no I/O space
arch/score/include/asm/io.h:#include <asm-generic/io.h>
No PCI support
arch/unicore32/include/asm/io.h:#include <asm-generic/io.h>
unicore32 is broken currently, the patch fixes it.
arch/xtensa/include/asm/io.h:#include <asm-generic/io.h>
PCI_IOBASE=0, IO_SPACE_LIMIT=0xffffffff, so no change.
Doesn't appear to define PCI_IOBASE.
Maybe there's other patches required for these?
For most of these, I assume we actually want to remove support for inb/outb as they don't support I/O space accesses. The other ones look correct to me.
Right, so:
#ifdef CONFIG_HAS_IOPORT #ifndef CONFIG_GENERIC_IOMAP static inline void __iomem *ioport_map(unsigned long port, unsigned int nr) { return (void __iomem *) port; }
changing that to include PCI_IOBASE in there will result in a build failure if the C compiler sees that. In other words, when HAS_IOPORT=y and GENERIC_IOMAP=n.
HAS_IOPORT is set when HAS_IOMEM is also set and NO_IOPORT unset.
It looks to me like blackfin doesn't set NO_IOPORT nor NO_IOMEM, so this would have HAS_IOPORT set, and from what I can see doesn't set GENERIC_IOMAP. So, this change probably breaks blackfin.
I haven't looked deeply at the others.