After
| commit d8191fa4
| Author: Alex Chiang <achiang@hp.com>
| Date:   Mon Feb 22 12:11:39 2010 -0700
|
|    ACPI: processor: driver doesn't need to evaluate _PDC
|
|    Now that the early _PDC evaluation path knows how to correctly
|    evaluate _PDC on only physically present processors, there's no
|    need for the processor driver to evaluate it later when it loads.
|
|    To cover the hotplug case, push _PDC evaluation down into the
|    hotplug paths.

only cpu with Processor Statement get processed with _PDC

If bios is using Device object instead of Processor statement.
SSDTs for Pstate/Cstate/Tstate can not be loaded dynamically.

Need to try to scan ACPI0007 in addition to Processor.

That commit is between 2.6.34-rc1 and 2.6.34-rc2, so stable tree for 2.6.34+
need this patch.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Reviewed-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

per comments in the bug report, this entry
seems to hurt at much as it helps.

https://bugzilla.kernel.org/show_bug.cgi?id=10807



Signed-off-by: Len Brown <len.brown@intel.com>

The commit 5d554a7b (ACPI: processor: add internal
processor_physically_present()) is broken on uniprocessor (UP)
configurations, as acpi_get_cpuid() will always return -1.

We use the value of num_possible_cpus() to tell us whether we got
an invalid cpuid from acpi_get_cpuid() in the SMP case, or if
instead, we are UP, in which case num_possible_cpus() is #defined
as 1.

We use num_possible_cpus() instead of num_online_cpus() to
protect ourselves against the scenario of CPU hotplug, and we've
taken down all the CPUs except one.

Thanks to Jan Pogadl for initial report and analysis and Chen
Gong for review.

https://bugzilla.kernel.org/show_bug.cgi?id=16357



Reported-by: Jan Pogadl <pogadl.jan@googlemail.com&gt;:>
Reviewed-by: Chen Gong <gong.chen@linux.intel.com>
Signed-off-by: Alex Chiang <achiang@canonical.com>
Signed-off-by: Len Brown <len.brown@intel.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py



The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

There's no real need for a pointer to the MADT to be global. The only
function who uses it is map_madt_entry.

This allows us to remove some more ugly #ifdefs.

Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Un-nest the if statements for readability.

Remove comments that re-state the obvious.

Change the control flow so that we no longer need a temp variable.

Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Untangle the nested if conditions to make this function look
more similar to the other map_*apic_id() functions.

Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Untangle the if() statement a little for readability.

Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Now that the early _PDC evaluation path knows how to correctly
evaluate _PDC on only physically present processors, there's no
need for the processor driver to evaluate it later when it loads.

To cover the hotplug case, push _PDC evaluation down into the
hotplug paths.

Cc: x86@kernel.org
Cc: Tony Luck <tony.luck@intel.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Now that we check for physically present processors before blindly
evaluating _PDC, we no longer need to maintain a DMI opt-in table
nor a kernel param.

Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Detect if a processor is physically present before evaluating _PDC.

We want this because some BIOS will provide a _PDC even for processors
that are not present. These bogus _PDC methods then attempt to load
non-existent tables, which causes problems.

Avoid those bogus landmines.

Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Enumerating processors (via MADT/_MAT) belongs in the processor core,
which is always built-in, rather than living in the processor driver
which may not be built.

Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

We've renamed the old processor_core.c to processor_driver.c, to
convey the idea that it can be built modular and has driver-like
bits.

Now let's re-create a processor_core.c for the bits needed
statically by the rest of the kernel. The contents of processor_pdc.c
are a good starting spot, so let's just rename that file and
complete our three card monte.

Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

If we evaluate _PDC in the early path, we do not want to evaluate
it again when the processor driver is loaded.

Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Allow platforms not listed in DMI table
to opt-in and evaluate _PDC early.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Commit 78f16996 (ACPI: processor: call _PDC early) blindly walks
the namespace and calls _PDC on every processor object it finds.

This change may cause issues on platforms that declare dummy
values for SSDTs on non-present processors (disabled in MADT).
When we call _PDC and dynamically attempt to execute the AML
Load() op on these dummy SSDTs, there's no telling what might
happen.

Rather than finding every platform that has bogus SSDTs, restrict
early _PDC calls to platforms that are known to need early
evaluation of _PDC.

This is a minimal, temporary fix (given the context of the
current release cycle). A real solution of checking the MADT for
non-present processors will be written for the next merge window.

References:

	http://bugzilla.kernel.org/show_bug.cgi?id=14710
	http://bugzilla.kernel.org/show_bug.cgi?id=14954



Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Alex Chiang introduced acpi_early_processor_set_pdc() in commit:
 ACPI: processor: call _PDC early
 78f16996

But this results in a section mismatch:

WARNING: drivers/acpi/acpi.o(.text+0xa9c1): Section mismatch in reference from the
function acpi_early_processor_set_pdc() to the variable .cpuinit.data:processor_idle_dmi_table
The function acpi_early_processor_set_pdc() references
the variable __cpuinitdata processor_idle_dmi_table.
This is often because acpi_early_processor_set_pdc lacks a __cpuinitdata
annotation or the annotation of processor_idle_dmi_table is wrong.

The only caller of acpi_early_processor_set_pdc() is acpi_bus_init() which
is an "__init" function. So the correct fix here is to mark
acpi_early_processor_set_pdc() "__init" too.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

When calling _PDC, we really only need the handle to the processor
to call the method; we don't look at any other parts of the
struct acpi_processor * given to us.

In the early path, when we walk the namespace, we are given the
handle directly, so just pass it through to acpi_processor_set_pdc()
without stuffing it into a wasteful struct acpi_processor allocated
on the stack each time

This saves 2834 bytes of stack.

Update the interface accordingly.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

We have the acpi_object_list * right there in acpi_processor_set_pdc()
so it doesn't seem necessary for an entire helper function just to
free it.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

acpi_processor_eval_pdc() really only needs a handle and an
acpi_object_list * to do its work.

No need to pass in a struct acpi_processor *, so let's be more specific
about what we want.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

acpi_processor_init_pdc() isn't really doing anything interesting
with the struct acpi_processor * parameter. Its real job is to allocate
the buffer for the _PDC bits.

So rename the function to acpi_processor_alloc_pdc(), and just return
the struct acpi_object_list * it's supposed to allocate.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

The x86 and ia64 implementations of the function in $subject are
exactly the same.

Also, since the arch-specific implementations of setting _PDC have
been completely hollowed out, remove the empty shells.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

The only thing arch-specific about calling _PDC is what bits get
set in the input obj_list buffer.

There's no need for several levels of indirection to twiddle those
bits. Additionally, since we're just messing around with a buffer,
we can simplify the interface; no need to pass around the entire
struct acpi_processor * just to get at the buffer.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Both x86 and ia64 initialize _PDC with mostly common bit settings.

Factor out the common settings and leave the arch-specific ones alone.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

The x86 and ia64 implementations of arch_acpi_processor_init_pdc()
are almost exactly the same. The only difference is in what bits
they set in obj_list buffer.

Combine the boilerplate memory management code, and leave the
arch-specific bit twiddling in separate implementations.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

arch dependent helper function that tells us if we should attempt to
evaluate _PDC on this machine or not.

The x86 implementation assumes that the CPUs in the machine must be
homogeneous, and that you cannot mix CPUs of different vendors.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

We discovered that at least one machine (HP Envy), methods in the DSDT
attempt to call external methods defined in a dynamically loaded SSDT.

Unfortunately, the DSDT methods we are trying to call are part of the
EC initialization, which happens very early, and the the dynamic SSDT
is only loaded when a processor _PDC method runs much later.

This results in namespace lookup errors for the (as of yet) undefined
methods.

Since Windows doesn't have any issues with this machine, we take it
as a hint that they must be evaluating _PDC much earlier than we are.

Thus, the proper thing for Linux to do should be to match the Windows
implementation more closely.

Provide a mechanism to call _PDC before we enable the EC. Doing so loads
the dynamic tables, and allows the EC to be enabled correctly.

The ACPI processor driver will still evaluate _PDC in its .add() method
to cover the hotplug case.

Resolves: http://bugzilla.kernel.org/show_bug.cgi?id=14824



Cc: ming.m.lin@intel.com
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>