[PATCH v4 0/9] Prefer using _OSC method over deprecated _PDC

[Michal Wilczynski]

ACPI 3.0 introduced a new Operating System Capabilities _OSC control
method. This method is similar to _PDC, which was marked as deprecated
in ACPI 3.0.

Prefer using _OSC method over deprecated _PDC in the acpi_bus_init(). In
case of the failure of the _OSC, try using _PDC as a fallback.

Testing done:
Tested on physical server with BIOS implementing _OSC methods. In this
case acpi_processor_osc() was executed for each CPU core. acpi_run_osc()
returned success indicating that _OSC method succeeded.

Tested on qemu VM to check whether the code would work on a SeaBios (the
default for qemu, doesn't support _OSC methods, or _PDC). This way I was
able to see how code behaves in case BIOS doesn't implement _OSC. In
that case the function
acpi_run_osc() returned failure, which propagated all the way up to
acpi_early_processor_osc(). The logic responsible for triggering _PDC
execution was triggered correctly.

Tested this using debug messages with printk.

v4:
 - move setting processor capabilities bits into arch code
 - move workaround for mwait to acpi/x86 directory
 - rename ACPI_PDC* constants to more generic ACPI_PROC_CAP*
 - introduce new function acpi_early_processor_control_setup()

v3:
 - split into more commits to make review easier
 - changed "_UID" to METHOD_NAME_UID
 - changed hard-coded constant to ACPI_PDC_COLLAB_PROC_PERF
 - added Suggested-by tags
 - fixed style issues
 - fixed whitespaces
 - refactored code
v2:
 - fixed compilation issues on ia64 and arm

Michal Wilczynski (9):
  acpi: Move mwait quirk out of acpi_processor.c
  acpi: Move processor_physically_present() to acpi_processor.c
  acpi: Refactor arch_acpi_set_pdc_bits()
  acpi: Rename ACPI_PDC constants
  acpi: Clear C_C2C3_FFH and C_C1_FFH in arch_acpi_set_proc_cap_bits()
  acpi: Move setting CAP_SMP_T_SWCOORD to arch_acpi_set_proc_cap_bits()
  acpi: Introduce acpi_processor_osc()
  acpi: Use _OSC method to convey processor OSPM capabilities
  acpi: Remove acpi_hwp_native_thermal_lvt_osc()

 arch/ia64/include/asm/acpi.h  |   6 +-
 arch/x86/include/asm/acpi.h   |  24 ++++---
 arch/x86/xen/enlighten_pv.c   |   8 +--
 drivers/acpi/acpi_processor.c | 121 +++++++++++++++++++++++++---------
 drivers/acpi/bus.c            |   5 +-
 drivers/acpi/internal.h       |  10 ++-
 drivers/acpi/processor_pdc.c  |  97 +--------------------------
 drivers/acpi/x86/utils.c      |  35 ++++++++++
 include/acpi/pdc_intel.h      |  36 ----------
 include/acpi/proc_cap_intel.h |  40 +++++++++++
 10 files changed, 194 insertions(+), 188 deletions(-)
 delete mode 100644 include/acpi/pdc_intel.h
 create mode 100644 include/acpi/proc_cap_intel.h

-- 
2.41.0