At present the lppaca - the structure shared with the iSeries
hypervisor and phyp - is contained within the PACA, our own low-level
per-cpu structure.  This doesn't have to be so, the patch below
removes it, making a separate array of lppaca structures.

This saves approximately 500*NR_CPUS bytes of image size and kernel
memory, because we don't need aligning gap between the Linux and
hypervisor portions of every PACA.  On the other hand it means an
extra level of dereference in many accesses to the lppaca.

The patch also gets rid of several places where we assign the paca
address to a local variable for no particular reason.
Signed-off-by: NDavid Gibson <dwg@au1.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

iSeries doesn't need to set the htab_address explicitly, htab_initialize()
will do it for us later.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

To make iSeries just a teensy bit less special, create ibm,pft-size properties
in the iSeries device tree. We can then rely on htab_dt_scan_pftsize() to set
ppc64_pft_size for us.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Connect iSeries up to the standard early debugging infrastructure.

To actually use this you need to enable the iSeries early debugging
in setup_64.c. Then after the messages are logged hit Ctrl-x Ctrl-x on
your console to dump the Hypervisor console buffer.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Hide some of the iseries details in iSeries_get_irq.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

log_plpar_hcall_return is only used on PPC_PSERIES, so move
it closer to its users and inside ifdef CONFIG_PPC_PSERIES.

remove the last vestiges of systemcfg in iSeries.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

This also make klimit have the same type on 32-bit as on 64-bit,
namely unsigned long, and defines and initializes it in one place.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

This patch merges platform codes.  systemcfg->platform is no longer used,
systemcfg use in general is deprecated as much as possible (and renamed
_systemcfg before it gets completely moved elsewhere in a future patch),
_machine is now used on ppc64 along as ppc32.  Platform codes aren't gone
yet but we are getting a step closer. A bunch of asm code in head[_64].S
is also turned into C code.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Make some changes to the NEED_RESCHED and POLLING_NRFLAG to reduce
confusion, and make their semantics rigid.  Improves efficiency of
resched_task and some cpu_idle routines.

* In resched_task:
- TIF_NEED_RESCHED is only cleared with the task's runqueue lock held,
  and as we hold it during resched_task, then there is no need for an
  atomic test and set there. The only other time this should be set is
  when the task's quantum expires, in the timer interrupt - this is
  protected against because the rq lock is irq-safe.

- If TIF_NEED_RESCHED is set, then we don't need to do anything. It
  won't get unset until the task get's schedule()d off.

- If we are running on the same CPU as the task we resched, then set
  TIF_NEED_RESCHED and no further action is required.

- If we are running on another CPU, and TIF_POLLING_NRFLAG is *not* set
  after TIF_NEED_RESCHED has been set, then we need to send an IPI.

Using these rules, we are able to remove the test and set operation in
resched_task, and make clear the previously vague semantics of
POLLING_NRFLAG.

* In idle routines:
- Enter cpu_idle with preempt disabled. When the need_resched() condition
  becomes true, explicitly call schedule(). This makes things a bit clearer
  (IMO), but haven't updated all architectures yet.

- Many do a test and clear of TIF_NEED_RESCHED for some reason. According
  to the resched_task rules, this isn't needed (and actually breaks the
  assumption that TIF_NEED_RESCHED is only cleared with the runqueue lock
  held). So remove that. Generally one less locked memory op when switching
  to the idle thread.

- Many idle routines clear TIF_POLLING_NRFLAG, and only set it in the inner
  most polling idle loops. The above resched_task semantics allow it to be
  set until before the last time need_resched() is checked before going into
  a halt requiring interrupt wakeup.

  Many idle routines simply never enter such a halt, and so POLLING_NRFLAG
  can be always left set, completely eliminating resched IPIs when rescheduling
  the idle task.

  POLLING_NRFLAG width can be increased, to reduce the chance of resched IPIs.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Con Kolivas <kernel@kolivas.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Run idle threads with preempt disabled.

Also corrected a bugs in arm26's cpu_idle (make it actually call schedule()).
How did it ever work before?

Might fix the CPU hotplugging hang which Nigel Cunningham noted.

We think the bug hits if the idle thread is preempted after checking
need_resched() and before going to sleep, then the CPU offlined.

After calling stop_machine_run, the CPU eventually returns from preemption and
into the idle thread and goes to sleep.  The CPU will continue executing
previous idle and have no chance to call play_dead.

By disabling preemption until we are ready to explicitly schedule, this bug is
fixed and the idle threads generally become more robust.

From: alexs <ashepard@u.washington.edu>

  PPC build fix

From: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>

  MIPS build fix
Signed-off-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NYoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The ancient ppcdebug/PPCDBG mechanism is now only used in two places.
First, in the hash setup code, one of the bits allows the size of the
hash table to be reduced by a factor of 8 - which would be better
accomplished with a command line option for that purpose.  The other
was a bunch of bus walking related messages in the iSeries code, which
would seem to be insufficient reason to keep the mechanism.

This patch removes the last traces of this mechanism.

Built and booted on iSeries and pSeries POWER5 LPAR (ARCH=powerpc).
Signed-off-by: NDavid Gibson <dwg@au1.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Adds a new CONFIG_PPC_64K_PAGES which, when enabled, changes the kernel
base page size to 64K.  The resulting kernel still boots on any
hardware.  On current machines with 4K pages support only, the kernel
will maintain 16 "subpages" for each 64K page transparently.

Note that while real 64K capable HW has been tested, the current patch
will not enable it yet as such hardware is not released yet, and I'm
still verifying with the firmware architects the proper to get the
information from the newer hypervisors.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

These days, the NACA only exists on iSeries.  Therefore, this patch
moves naca.h from include/asm-ppc64 to arch/powerpc/platforms/iseries.
There was one file including naca.h outside of platforms/iseries -
arch/ppc64/kernel/udbg_scc.c.  However, that's obviously a hangover
from older days.  The include is not necessary, so this patch simply
removes it.

Built and booted on iSeries, built for G5 (which uses udbg_scc.o).
Signed-off-by: NDavid Gibson <dwg@au1.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Signed-off-by: NKelly Daly <kelly@au.ibm.com>

Signed-off-by: NKelly Daly <kelly@au.ibm.com>

Signed-off-by: NKelly Daly <kelly@au.ibm.com>

Signed-off-by: NKelly Daly <kelly@au.ibm.com>

Signed-off-by: NKelly Daly <kelly@au.ibm.com>

Signed-off-by: NKelly Daly <kelly@au.ibm.com>

Signed-off-by: NKelly Daly <kelly@au.ibm.com>

By parsing the command line earlier, we can add the mem= value to the
flattened device tree and let the generic code sort out the memory limit
for us.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

We had a static memory_limit in prom.c, and then another one defined
in setup_64.c and used in numa.c, which resulted in the kernel crashing
when mem=xxx was given on the command line.  This puts the declaration
in system.h and the definition in mem.c.  This also moves the
definition of tce_alloc_start/end out of setup_64.c.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

... for consistency with ppc32; also add in ppc32's show_percpuinfo
function.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

A few things change for consistency between ppc32 and ppc64:
idle functions return void; *_get_boot_time functions return
unsigned long (i.e. time_t) rather than filling in a struct rtc_time
(since that's useful to the callers and easier for pmac to
generate); *_get_rtc_time and *_set_rtc_time functions take
a struct rtc_time; irq_canonicalize is gone; nvram_sync returns
void.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

On ARCH=ppc64 we were getting htab_hash_mask recalculated
to the correct value for our particular machine by accident.
In the merge tree, that code was commented out, so htab_hash_mask
was being corrupted.

We now set ppc64_pft_size instead which gets htab_has_mask
calculated correctly for us later.  We should put an
ibm,pft-size property in the device tree at some point.

Also set -mno-minimal-toc in some makefiles.
Allow iSeries to configure PROC_DEVICETREE.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

These files are only referenced from within
arch/powerpc/platforms/iseries, so move them there.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

iSeries_setup.c becomes setup.c
iSeries_setup.h becomes setup.h
mf.c retains its name

Also moved iSeries_[gs]et_rtc_time and iSeries_get_boot_time into
mf.c since they are just small wrappers around mf_ functions.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

This is obsolete.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Add the /cpus node and nodes for each cpu, as well as cache size properties,
reg propery, "linux,boot-cpu", and timebase/clock frequency.

With those properties in place we can remove:

- setup_iSeries_cache_sizes()
- code in iSeries_setup_arch() to calculate timebase etc.
- iSeries_calibrate_decr()
- smp_iSeries_numProcs() and simplify smp_iSeries_probe()
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Add /chosen/linux,platform to the device tree so we can remove iSeries
specific code in setup_system() to set systemcfg->platform.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

This patch adds the required nodes to the iSeries device tree to allow
early_init_devtree() to do the lmb setup for us.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Misc steps to incorporate the flat device tree on iSeries.

- define iseries_probe()
- call build_iSeries_Memory_Map() earlier
- return __pa() of the flat device tree from iSeries_early_setup()
- actually call early_setup() for iSeries
- add iseries_md to machdep_calls
- build prom.o for iSeries
- enable /proc/device-tree for iSeries
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

This patch adds infrastructure for creating a fake flattened device tree
on iSeries.

We also need to build prom.o for iSeries which means we'll always need it.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

early_setup() calls htab_initialize() which is similar, but not identical
to iSeries_bolt_kernel().

On iSeries the Hypervisor has already inserted some ptes for us, and we
simply have to detect that and bolt them. iSeries_hpte_bolt_or_insert()
implements that logic.

For the case of a non-existing pte we just call iSeries_hpte_insert(). This
appears to work, although it's not entirely equivalent to the old code in
iSeries_make_pte() which panicked if we got a secondary slot. Not sure if
that's important.

Finally we call iSeries_hpte_bolt_or_insert() from create_pte_mapping(),
which is called from htab_initialize() for each lmb region.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

In order to call finish_device_tree() on iSeries we need to define
virt_irq_create_mapping(). We also need to set ppc64_interrupt_controller to
something other than zero. If we want to do interrupt setup via the device
tree on iSeries this code will need some serious work, but it's harmless to
have it there as long as the nodes in the iSeries device tree don't cause
it to be invoked.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Move the iSeries machine specific calls into a machdep_calls struct like
other platforms, rather than setting members of ppc_md explicitly.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

This patch moves power4_enable_pmcs() to arch/ppc64/kernel/pmc.c.

I've tested it on P5 LPAR and P4. It does what it used to.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Rename the msChunks struct to get rid of the StUdlY caps and make it a bit
clearer what it's for.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>