[CPUFREQ] Enable ACPI PDC handshake for VIA/Centaur CPUs
authorHarald Welte <HaraldWelte@viatech.com>
Tue, 24 Nov 2009 15:53:00 +0000 (16:53 +0100)
committerDave Jones <davej@redhat.com>
Tue, 24 Nov 2009 18:33:32 +0000 (13:33 -0500)
commitd77b81974521c82fa6fda38dfff1b491dcc62a32
tree7095c29ad0f300e4f8838e195088d1639bf67628
parenta8a8a669ea13d792296737505adc43ccacf3a648
[CPUFREQ] Enable ACPI PDC handshake for VIA/Centaur CPUs

In commit 0de51088e6a82bc8413d3ca9e28bbca2788b5b53, we introduced the
use of acpi-cpufreq on VIA/Centaur CPU's by removing a vendor check for
VENDOR_INTEL.  However, as it turns out, at least the Nano CPU's also
need the PDC (processor driver capabilities) handshake in order to
activate the methods required for acpi-cpufreq.

Since arch_acpi_processor_init_pdc() contains another vendor check for
Intel, the PDC is not initialized on VIA CPU's.  The resulting behavior
of a current mainline kernel on such systems is:  acpi-cpufreq
loads and it indicates CPU frequency changes.  However, the CPU stays at
a single frequency

This trivial patch ensures that init_intel_pdc() is called on Intel and
VIA/Centaur CPU's alike.

Signed-off-by: Harald Welte <HaraldWelte@viatech.com>
Signed-off-by: Dave Jones <davej@redhat.com>
arch/x86/kernel/acpi/processor.c