lkml.org 
[lkml]   [2012]   [Apr]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 0/5] ACPI: Add _OST support for ACPI hotplug
From
Date
On Wed, 2012-04-11 at 10:33 -0600, Shuah Khan wrote:
> On Tue, 2012-04-10 at 16:21 -0600, Toshi Kani wrote:
> > This series of patches supports ACPI _OST (OSPM Status Indication)
> > method for ACPI-based CPU and memory hotplug operations. After
> > ACPI-based hotplug operation completed, OSPM calls _OST to convey
> > the completion status to ACPI firmware. If _OST is not present,
> > this change has no effect on the platform.
> >
> > The _OST definition can be found in section 6.3.5 of ACPI 5.0 spec.
> > The HPPF spec below also describes hotplug flows with _OST.
> >
> > DIG64 Hot-Plug & Partitioning Flow (HPPF) Specification R1.0
> > http://www.dig64.org/home/DIG64_HPPF_R1_0.pdf
> >
> > The change was tested by overriding DSDT with fake _OST methods.
>
> Could you please elaborate what it means by fake _OST method? I am
> assuming based on the above that this patch set was never tested on real
> hardware that has support for _OST method? Is that correct? If so why
> not wait until you have the opportunity to test it on real hardware
> before sending the patch?

Hi Shuah,

The fake _OST methods print arguments to verify successful execution of
the methods. Since the purpose of _OST is firmware-internal
communication, there is no difference in testing on real firmware from
the OS perspective. Overriding DSDT with fake ACPI methods is a
well-established and widely used testing method as well.

Pre-enablement of new features will benefit us because:

1. There is a timeline gap between support in the upstream kernel and
distribution kernels. Also, a new platform often needs to support older
stable kernels as well.

2. Pre-enablement in the OS allows platform vendors to design new
platforms that utilize the new feature.

Thanks,
-Toshi


> -- Shuah
> >
> > ---
> > Toshi Kani (4):
> > ACPI: Set hotplug _OST support bit to _OSC
> > ACPI: Add acpi_evaluate_ost() for calling _OST
> > ACPI: Add _OST support for ACPI CPU hotplug
> > ACPI: Add _OST support for ACPI memory hotplug
> >
> > drivers/acpi/acpi_memhotplug.c | 43 +++++++++++++++++++++++++++++----------
> > drivers/acpi/bus.c | 5 ++++
> > drivers/acpi/processor_driver.c | 28 ++++++++++++++++++-------
> > drivers/acpi/utils.c | 34 ++++++++++++++++++++++++++++++
> > include/acpi/acpi_bus.h | 3 ++
> > include/linux/acpi.h | 26 ++++++++++++++++++++++-
> > 6 files changed, 119 insertions(+), 20 deletions(-)
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at http://www.tux.org/lkml/
> >
>
>




\
 
 \ /
  Last update: 2012-04-11 20:55    [from the cache]
©2003-2011 Jasper Spaans