From d77b81974521c82fa6fda38dfff1b491dcc62a32 Mon Sep 17 00:00:00 2001 From: Harald Welte <HaraldWelte@viatech.com> Date: Tue, 24 Nov 2009 16:53:00 +0100 Subject: [PATCH] [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 | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/acpi/processor.c b/arch/x86/kernel/acpi/processor.c index d296f4a195c9..d85d1b2432ba 100644 --- a/arch/x86/kernel/acpi/processor.c +++ b/arch/x86/kernel/acpi/processor.c @@ -79,7 +79,8 @@ void arch_acpi_processor_init_pdc(struct acpi_processor *pr) struct cpuinfo_x86 *c = &cpu_data(pr->id); pr->pdc = NULL; - if (c->x86_vendor == X86_VENDOR_INTEL) + if (c->x86_vendor == X86_VENDOR_INTEL || + c->x86_vendor == X86_VENDOR_CENTAUR) init_intel_pdc(pr, c); return; -- GitLab