This rewrites pretty much from scratch the handling of MMIO and PIO
space allocations on powerpc64.  The main goals are:

 - Get rid of imalloc and use more common code where possible
 - Simplify the current mess so that PIO space is allocated and
   mapped in a single place for PCI bridges
 - Handle allocation constraints of PIO for all bridges including
   hot plugged ones within the 2GB space reserved for IO ports,
   so that devices on hotplugged busses will now work with drivers
   that assume IO ports fit in an int.
 - Cleanup and separate tracking of the ISA space in the reserved
   low 64K of IO space. No ISA -> Nothing mapped there.

I booted a cell blade with IDE on PIO and MMIO and a dual G5 so
far, that's it :-)

With this patch, all allocations are done using the code in
mm/vmalloc.c, though we use the low level __get_vm_area with
explicit start/stop constraints in order to manage separate
areas for vmalloc/vmap, ioremap, and PCI IOs.

This greatly simplifies a lot of things, as you can see in the
diffstat of that patch :-)

A new pair of functions pcibios_map/unmap_io_space() now replace
all of the previous code that used to manipulate PCI IOs space.
The allocation is done at mapping time, which is now called from
scan_phb's, just before the devices are probed (instead of after,
which is by itself a bug fix). The only other caller is the PCI
hotplug code for hot adding PCI-PCI bridges (slots).

imalloc is gone, as is the "sub-allocation" thing, but I do beleive
that hotplug should still work in the sense that the space allocation
is always done by the PHB, but if you unmap a child bus of this PHB
(which seems to be possible), then the code should properly tear
down all the HPTE mappings for that area of the PHB allocated IO space.

I now always reserve the first 64K of IO space for the bridge with
the ISA bus on it. I have moved the code for tracking ISA in a separate
file which should also make it smarter if we ever are capable of
hot unplugging or re-plugging an ISA bridge.

This should have a side effect on platforms like powermac where VGA IOs
will no longer work. This is done on purpose though as they would have
worked semi-randomly before. The idea at this point is to isolate drivers
that might need to access those and fix them by providing a proper
function to obtain an offset to the legacy IOs of a given bus.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

arch/powerpc/platforms/pseries/pseries.h:24: warning: return type defaults to 'int'
arch/powerpc/platforms/pseries/pseries.h:25: warning: return type defaults to 'int'
arch/powerpc/platforms/pseries/pseries.h:24: warning: control reaches end of non-void function
arch/powerpc/platforms/pseries/pseries.h:25: warning: control reaches end of non-void function
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

During power outages, the UPS notifies the system for a shutdown.
In the current setup, it isn't possible to poweron when power is
restored.  This patch fixes the issue by calling the right
ibm,power-off-ups token during such events.  It also adds a sysfs
interface so userspace can specify whether or not to power on when
power is restored.
Signed-off-by: NManish Ahuja <ahuja@austin.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

My "cleanup" patch (dce623e0) had a cut
and paste error for the !CONFIG_KEXEC case. Fifty lashes for me.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Move all the pseries kexec code into one file, platforms/pseries/kexec.c
Provide helpers for setting up ppc_md.kexec_cpu_down, so that we don't
have to have #ifdef CONFIG_KEXEC in setup.c

Move the initialisation of the ppc_md kexec callbacks into an init routine.
This is well and truly early enough to cause no change in behaviour, we
can't kexec until userspace has given us a kernel to kexec into.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Move some extern declarations from setup.c into the new pseries.h.
While we're at it, provide dummy implementations for !SMP, to avoid
cluttering the C file with more #ifdefs.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Following the example of platforms/pasemi, consolidate a couple of
tiny header files in platforms/pseries into pseries.h.

This gives us a convenient place to put things that need to be
available to the platform code, but not public. And hopefully will
help people resist the temptation of sticking externs in C files.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>