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| author | Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> | 2005-04-15 15:07:10 -0400 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2005-07-12 00:14:36 -0400 |
| commit | 02df8b9385c21fdba165bd380f60eca1d3b0578b (patch) | |
| tree | 988ad0e0ca73a40993fb1458d5cd19f90f922b31 /drivers/acpi/processor_core.c | |
| parent | 17e9c78a75ce9eacd61200f9e1f1924012e28846 (diff) | |
| download | linux-02df8b9385c21fdba165bd380f60eca1d3b0578b.tar.gz linux-02df8b9385c21fdba165bd380f60eca1d3b0578b.tar.bz2 linux-02df8b9385c21fdba165bd380f60eca1d3b0578b.zip | |
[ACPI] enable C2 and C3 idle power states on SMP
http://bugzilla.kernel.org/show_bug.cgi?id=4401
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/processor_core.c')
| -rw-r--r-- | drivers/acpi/processor_core.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c index f4778747e889..e421842888b9 100644 --- a/drivers/acpi/processor_core.c +++ b/drivers/acpi/processor_core.c @@ -256,6 +256,43 @@ acpi_processor_errata ( /* -------------------------------------------------------------------------- + Common ACPI processor fucntions + -------------------------------------------------------------------------- */ + +/* + * _PDC is required for a BIOS-OS handshake for most of the newer + * ACPI processor features. + */ + +int acpi_processor_set_pdc(struct acpi_processor *pr, + struct acpi_object_list *pdc_in) +{ + acpi_status status = AE_OK; + u32 arg0_buf[3]; + union acpi_object arg0 = {ACPI_TYPE_BUFFER}; + struct acpi_object_list no_object = {1, &arg0}; + struct acpi_object_list *pdc; + + ACPI_FUNCTION_TRACE("acpi_processor_set_pdc"); + + arg0.buffer.length = 12; + arg0.buffer.pointer = (u8 *) arg0_buf; + arg0_buf[0] = ACPI_PDC_REVISION_ID; + arg0_buf[1] = 0; + arg0_buf[2] = 0; + + pdc = (pdc_in) ? pdc_in : &no_object; + + status = acpi_evaluate_object(pr->handle, "_PDC", pdc, NULL); + + if ((ACPI_FAILURE(status)) && (pdc_in)) + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Error evaluating _PDC, using legacy perf. control...\n")); + + return_VALUE(status); +} + + +/* -------------------------------------------------------------------------- FS Interface (/proc) -------------------------------------------------------------------------- */ |