/* * Line 6 Linux USB driver * * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation, version 2. * */ #ifndef MIDIBUF_H #define MIDIBUF_H struct midi_buffer { unsigned char *buf; int size; int split; int pos_read, pos_write; int full; int command_prev; }; extern int line6_midibuf_bytes_used(struct midi_buffer *mb); extern int line6_midibuf_bytes_free(struct midi_buffer *mb); extern void line6_midibuf_destroy(struct midi_buffer *mb); extern int line6_midibuf_ignore(struct midi_buffer *mb, int length); extern int line6_midibuf_init(struct midi_buffer *mb, int size, int split); extern int line6_midibuf_read(struct midi_buffer *mb, unsigned char *data, int length); extern void line6_midibuf_reset(struct midi_buffer *mb); extern int line6_midibuf_write(struct midi_buffer *mb, unsigned char *data, int length); #endif on value='emaclite-cleanup'>emaclite-cleanup net-next plumbingsTobias Klauser
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authorSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>2017-02-03 14:18:39 -0800
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2017-02-04 00:11:08 +0100
commit6e978b22efa1db9f6e71b24440b5f1d93e968ee3 (patch)
treec666f7a26b860674848949e39a610222b0723f89 /net/rds/rds_single_path.h
parent3c223c19aea85d3dda1416c187915f4a30b04b1f (diff)
cpufreq: intel_pstate: Disable energy efficiency optimization
Some Kabylake desktop processors may not reach max turbo when running in HWP mode, even if running under sustained 100% utilization. This occurs when the HWP.EPP (Energy Performance Preference) is set to "balance_power" (0x80) -- the default on most systems. It occurs because the platform BIOS may erroneously enable an energy-efficiency setting -- MSR_IA32_POWER_CTL BIT-EE, which is not recommended to be enabled on this SKU. On the failing systems, this BIOS issue was not discovered when the desktop motherboard was tested with Windows, because the BIOS also neglects to provide the ACPI/CPPC table, that Windows requires to enable HWP, and so Windows runs in legacy P-state mode, where this setting has no effect. Linux' intel_pstate driver does not require ACPI/CPPC to enable HWP, and so it runs in HWP mode, exposing this incorrect BIOS configuration. There are several ways to address this problem. First, Linux can also run in legacy P-state mode on this system. As intel_pstate is how Linux enables HWP, booting with "intel_pstate=disable" will run in acpi-cpufreq/ondemand legacy p-state mode. Or second, the "performance" governor can be used with intel_pstate, which will modify HWP.EPP to 0. Or third, starting in 4.10, the /sys/devices/system/cpu/cpufreq/policy*/energy_performance_preference attribute in can be updated from "balance_power" to "performance". Or fourth, apply this patch, which fixes the erroneous setting of MSR_IA32_POWER_CTL BIT_EE on this model, allowing the default configuration to function as designed. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Reviewed-by: Len Brown <len.brown@intel.com> Cc: 4.6+ <stable@vger.kernel.org> # 4.6+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'net/rds/rds_single_path.h')