This changes the writeX family of functions to have a sync instruction
before the MMIO store rather than after, because the generally expected
behaviour is that the device receiving the MMIO store can be guaranteed
to see the effects of any preceding writes to normal memory.
To preserve ordering between writeX and readX, and to preserve ordering
between preceding stores and the readX, the readX family of functions
have had an sync added before the load.
Although writeX followed by spin_unlock is not officially guaranteed
to keep the writeX inside the spin-locked region unless an mmiowb()
is used, there are currently drivers that depend on the previous
behaviour on powerpc, which was that the mmiowb wasn't actually required.
Therefore we have a per-cpu flag that is set by writeX, cleared by
__raw_spin_lock and mmiowb, and tested by __raw_spin_unlock. If it is
set, __raw_spin_unlock does a sync and clears it.
This changes both 32-bit and 64-bit readX/writeX. 32-bit already has a
sync in __raw_spin_unlock (since lwsync doesn't exist on 32-bit), and thus
doesn't need the per-cpu flag.
Tested on G5 (PPC970) and POWER5.
Signed-off-by: Paul Mackerras <paulus@samba.org>
These are build fixes that enable (for example) libata and the ide
code to actually build on iSeries. The associated hardware will never
be supported on legacy iSeries, so the code paths don't actually need
to work, but it is useful (especially for a combined kernel) if the
code can build.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Some people report that we die on some Macs when we are expecting to
catch machine checks after poking at some random I/O address. I'd seen
it happen on my dual G4 with serial ports until we fixed those to use
OF, but now other users are reporting it with i8042.
This expands the use of check_legacy_ioport() to avoid that situation
even on 32-bit kernels.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cleanup patch which removes the io_page_mask. It fixes the reset on
some e1000 devices which is needed for clean kexec reboots. The legacy
devices which broke with this patch (parallel port and PC speaker) have
now been fixed in Linus' tree.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
include/asm-ppc/ had #ifdef __KERNEL__ in all header files that
are not meant for use by user space, include/asm-powerpc does
not have this yet.
This patch gets us a lot closer there. There are a few cases
where I was not sure, so I left them out. I have verified
that no CONFIG_* symbols are used outside of __KERNEL__
any more and that there are no obvious compile errors when
including any of the headers in user space libraries.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
For these, I have just done the lame-o merge where the file ends up
looking like:
#ifndef CONFIG_PPC64
#include <asm-ppc/foo.h>
#else
... contents from asm-ppc64/foo.h
#endif
so nothing has changed, really, except that we reduce include/asm-ppc64
a bit more.
Signed-off-by: Paul Mackerras <paulus@samba.org>
