Commit Graph

69 Commits

Author SHA1 Message Date
Michael Ellerman c5e24354ef [PATCH] powerpc: Turn cpu_irq_down into kexec_cpu_down
We currently have a ppc_md member called cpu_irq_down, which disables IRQs
for the cpu in question. The only caller of cpu_irq_down is the kexec code.

On pSeries we need to do more than just teardown IRQs at kexec time, so rename
the ppc_md member to kexec_cpu_down and expand it. The pSeries code needs to
know, and other platforms might too, whether we're doing a crash shutdown (ie.
panicking) or a regular kexec, so add a flag for that.

The pSeries implementation of kexec_cpu_down does an unregister VPA call, which
tells the Hypervisor to stop writing stuff into our pacas. Without this we can
get weird memory corruption bugs when we kexec, caused by the Hypervisor
writing into the first kernel's pacas which happens to be somewhere interesting
in the second kernel's memory.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-14 16:33:09 +11:00
Anton Blanchard 50bcfec19f [PATCH] ppc64: Remove debug boot message
We have been printing the raw ppc64_firmware_features during boot. Since
we can work it out from the device tree, lets remove it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-11 22:20:04 +11:00
Paul Mackerras 799d6046d3 [PATCH] powerpc: merge code values for identifying platforms
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: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-10 13:37:51 +11:00
Nick Piggin 64c7c8f885 [PATCH] sched: resched and cpu_idle rework
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: Nick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:56:33 -08:00
Nick Piggin 5bfb5d690f [PATCH] sched: disable preempt in idle tasks
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: Nick Piggin <npiggin@suse.de>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:56:33 -08:00
Michael Ellerman 76032de898 [PATCH] powerpc: Make ppc_md.set_dabr non 64-bit specific
Define ppc_md.set_dabr for both 32 + 64 bit. Cleanup the implementation for
pSeries also, it was needlessly complex. Now we just do two firmware tests at
setup time, and use one of two functions, rather than using one function and
testing on every call.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-07 13:31:13 +11:00
Paul Mackerras 2249ca9d60 powerpc: Various UP build fixes
Mostly this involves adding #include <asm/smp.h>, since that defines
things like boot_cpuid[_phys] and [gs]et_hard_smp_processor_id, which
are SMP-related but still needed on UP.  This incorporates fixes
posted by Olof Johansson and Heikki Lindholm.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-07 13:18:13 +11:00
Michael Ellerman dc3a9efb5e Merge with Paulus 2005-11-04 12:12:52 +11:00
Michael Ellerman a121872032 powerpc: Move plpar_wrappers.h into arch/powerpc/platforms/pseries
Move plpar_wrappers.h into arch/powerpc/platforms/pseries, fixup white space,
and update callers.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
2005-11-03 15:33:31 +11:00
Michael Ellerman cab0af98df powerpc: Make set_dabr() a ppc_md function
Move pSeries specific code in set_dabr() into a ppc_md function, this will
allow us to keep plpar_wrappers.h private to platforms/pseries.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
2005-11-03 15:30:49 +11:00
Paul Mackerras f4fcbbe9a7 powerpc: Merge remaining RTAS code
This moves rtas-proc.c and rtas_flash.c into arch/powerpc/kernel, since
cell wants them as well as pseries (and chrp can use rtas-proc.c too,
at least in principle).  rtas_fw.c is gone, with its bits moved into
rtas_flash.c and rtas.c.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-03 14:41:19 +11:00
Paul Mackerras a39dbcf71e powerpc: Fix pseries (64-bit) build
A recent commit that removed rtas-fw.h and moved its contents to
include/asm-powerpc/rtas.h forgot to also remove the inclusion of
it in arch/powerpc/platforms/pseries/setup.c.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-01 22:37:47 +11:00
David Gibson 007e8f51b2 [PATCH] powerpc: Move xics.[ch] into platforms/pseries
This patch moves the XICS interrupt controller code into the
platforms/pseries directory, since it only appears on pSeries
machines.  If it ever appears on some other machine we can move it to
sysdev, although xics.c itself will need a bunch of changes in that
case to remove pSeries specific assumptions.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-28 16:39:19 +10:00
Paul Mackerras 033ef338b6 powerpc: Merge rtas.c into arch/powerpc/kernel
This splits arch/ppc64/kernel/rtas.c into arch/powerpc/kernel/rtas.c,
which contains generic RTAS functions useful on any CHRP platform,
and arch/powerpc/platforms/pseries/rtas-fw.[ch], which contain
some pSeries-specific firmware flashing bits.  The parts of rtas.c
that are to do with pSeries-specific error logging are protected
by a new CONFIG_RTAS_ERROR_LOGGING symbol.  The inclusion of rtas.o
is controlled by the CONFIG_PPC_RTAS symbol, and the relevant
platforms select that.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-26 17:05:24 +10:00
Paul Mackerras f9bd170a87 powerpc: Merge i8259.c into arch/powerpc/sysdev
This changes the parameters for i8259_init so that it takes two
parameters: a physical address for generating an interrupt
acknowledge cycle, and an interrupt number offset.  i8259_init
now sets the irq_desc[] for its interrupts; all the callers
were doing this, and that code is gone now.  This also defines
a CONFIG_PPC_I8259 symbol to select i8259.o for inclusion, and
makes the platforms that need it select that symbol.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-26 16:47:42 +10:00
Paul Mackerras 0458060c1c ppc64: Move init_boot_text call and conswitchp init into setup_arch
This way they get done in one place for all platforms, and it is
more consistent with what ppc32 does.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-20 21:00:20 +10:00
Paul Mackerras 0dd194d02d powerpc: Fix places where ppc_md.show_[per]cpuinfo was treated as int
I missed a few places where ppc code was still assuming that the
ppc_md.show_[per]cpuinfo functions returned int.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-20 20:48:19 +10:00
Paul Mackerras 143a1dec7e powerpc: Merge machdep.h
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: Paul Mackerras <paulus@samba.org>
2005-10-19 23:11:21 +10:00
Paul Mackerras 69a80d3f69 powerpc: move pSeries files to arch/powerpc/platforms/pseries
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 22:03:41 +10:00