From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wei Wang Subject: [PATCH v6 4/6] x86/intel_pstate: add a booting param to select the driver to load Date: Wed, 28 Oct 2015 11:21:16 +0800 Message-ID: <1446002478-16105-5-git-send-email-wei.w.wang@intel.com> References: <1446002478-16105-1-git-send-email-wei.w.wang@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1446002478-16105-1-git-send-email-wei.w.wang@intel.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: jbeulich@suse.com, andrew.cooper3@citrix.com, xen-devel@lists.xen.org, wei.liu2@citrix.com Cc: Wei Wang List-Id: xen-devel@lists.xenproject.org By default, the old P-state driver (acpi-freq) is used. Adding "intel_pstate" to the Xen booting param list to enable the use of intel_pstate. However, if intel_pstate is enabled on a machine which does not support the driver (e.g. Nehalem), the old P-state driver will be loaded due to the failure loading of intel_pstate. Also, adding the intel_pstate booting parameter to xen-command-line.markdown. Signed-off-by: Wei Wang --- changes in v6: 1) move the declaration of intel_pstate_init() to this patch. docs/misc/xen-command-line.markdown | 7 +++++++ xen/arch/x86/acpi/cpufreq/cpufreq.c | 15 ++++++++++----- xen/include/asm-x86/cpufreq.h | 2 ++ 3 files changed, 19 insertions(+), 5 deletions(-) diff --git a/docs/misc/xen-command-line.markdown b/docs/misc/xen-command-line.markdown index 416e559..e57a23a 100644 --- a/docs/misc/xen-command-line.markdown +++ b/docs/misc/xen-command-line.markdown @@ -858,6 +858,13 @@ debug hypervisor only). ### idle\_latency\_factor > `= ` +### intel\_pstate +> `= ` + +> Default: `false` + +Enable the loading of the intel pstate driver. + ### ioapic\_ack > `= old | new` diff --git a/xen/arch/x86/acpi/cpufreq/cpufreq.c b/xen/arch/x86/acpi/cpufreq/cpufreq.c index a2ba0db..d59f251 100644 --- a/xen/arch/x86/acpi/cpufreq/cpufreq.c +++ b/xen/arch/x86/acpi/cpufreq/cpufreq.c @@ -40,6 +40,7 @@ #include #include #include +#include #include #include @@ -647,11 +648,15 @@ static int __init cpufreq_driver_init(void) { int ret = 0; - if ((cpufreq_controller == FREQCTL_xen) && - (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)) - ret = cpufreq_register_driver(&acpi_cpufreq_driver); - else if ((cpufreq_controller == FREQCTL_xen) && - (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)) + if ( (cpufreq_controller == FREQCTL_xen) && + (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) ) + { + ret = intel_pstate_init(); + if ( ret ) + ret = cpufreq_register_driver(&acpi_cpufreq_driver); + } + else if ( (cpufreq_controller == FREQCTL_xen) && + (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) ) ret = powernow_register_driver(); return ret; diff --git a/xen/include/asm-x86/cpufreq.h b/xen/include/asm-x86/cpufreq.h index afc72df..3ff516d 100644 --- a/xen/include/asm-x86/cpufreq.h +++ b/xen/include/asm-x86/cpufreq.h @@ -22,6 +22,8 @@ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ +extern int intel_pstate_init(void); + /* * Maximum transition latency is in nanoseconds - if it's unknown, * CPUFREQ_ETERNAL shall be used. -- 1.9.1