Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq: (35 commits)
  [CPUFREQ] Prevent p4-clockmod from auto-binding to the ondemand governor.
  [CPUFREQ] Make cpufreq-nforce2 less obnoxious
  [CPUFREQ] p4-clockmod reports wrong frequency.
  [CPUFREQ] powernow-k8: Use a common exit path.
  [CPUFREQ] Change link order of x86 cpufreq modules
  [CPUFREQ] conservative: remove 10x from def_sampling_rate
  [CPUFREQ] conservative: fixup governor to function more like ondemand logic
  [CPUFREQ] conservative: fix dbs_cpufreq_notifier so freq is not locked
  [CPUFREQ] conservative: amend author's email address
  [CPUFREQ] Use swap() in longhaul.c
  [CPUFREQ] checkpatch cleanups for acpi-cpufreq
  [CPUFREQ] powernow-k8: Only print error message once, not per core.
  [CPUFREQ] ondemand/conservative: sanitize sampling_rate restrictions
  [CPUFREQ] ondemand/conservative: deprecate sampling_rate{min,max}
  [CPUFREQ] powernow-k8: Always compile powernow-k8 driver with ACPI support
  [CPUFREQ] Introduce /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_transition_latency
  [CPUFREQ] checkpatch cleanups for powernow-k8
  [CPUFREQ] checkpatch cleanups for ondemand governor.
  [CPUFREQ] checkpatch cleanups for powernow-k7
  [CPUFREQ] checkpatch cleanups for speedstep related drivers.
  ...

30 files changed, 1372 insertions, 995 deletions

diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt
index 5b0cfa67aff9..ce73f3eb5ddb 100644
--- a/Documentation/cpu-freq/governors.txt
+++ b/Documentation/cpu-freq/governors.txt
@@ -117,10 +117,28 @@ accessible parameters:
 sampling_rate: measured in uS (10^-6 seconds), this is how often you
 want the kernel to look at the CPU usage and to make decisions on
 what to do about the frequency.  Typically this is set to values of
-around '10000' or more.
-
-show_sampling_rate_(min|max): the minimum and maximum sampling rates
-available that you may set 'sampling_rate' to.
+around '10000' or more. It's default value is (cmp. with users-guide.txt):
+transition_latency * 1000
+The lowest value you can set is:
+transition_latency * 100 or it may get restricted to a value where it
+makes not sense for the kernel anymore to poll that often which depends
+on your HZ config variable (HZ=1000: max=20000us, HZ=250: max=5000).
+Be aware that transition latency is in ns and sampling_rate is in us, so you
+get the same sysfs value by default.
+Sampling rate should always get adjusted considering the transition latency
+To set the sampling rate 750 times as high as the transition latency
+in the bash (as said, 1000 is default), do:
+echo `$(($(cat cpuinfo_transition_latency) * 750 / 1000)) \
+    >ondemand/sampling_rate
+
+show_sampling_rate_(min|max): THIS INTERFACE IS DEPRECATED, DON'T USE IT.
+You can use wider ranges now and the general
+cpuinfo_transition_latency variable (cmp. with user-guide.txt) can be
+used to obtain exactly the same info:
+show_sampling_rate_min = transtition_latency * 500    / 1000
+show_sampling_rate_max = transtition_latency * 500000 / 1000
+(divided by 1000 is to illustrate that sampling rate is in us and
+transition latency is exported ns).
 
 up_threshold: defines what the average CPU usage between the samplings
 of 'sampling_rate' needs to be for the kernel to make a decision on
diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt
index 917918f84fc7..75f41193f3e1 100644
--- a/Documentation/cpu-freq/user-guide.txt
+++ b/Documentation/cpu-freq/user-guide.txt
@@ -152,6 +152,18 @@ cpuinfo_min_freq :		this file shows the minimum operating
                                 frequency the processor can run at(in kHz) 
 cpuinfo_max_freq :              this file shows the maximum operating
                                 frequency the processor can run at(in kHz) 
+cpuinfo_transition_latency      The time it takes on this CPU to
+                                switch between two frequencies in nano
+                                seconds. If unknown or known to be
+                                that high that the driver does not
+                                work with the ondemand governor, -1
+                                (CPUFREQ_ETERNAL) will be returned.
+                                Using this information can be useful
+                                to choose an appropriate polling
+                                frequency for a kernel governor or
+                                userspace daemon. Make sure to not
+                                switch the frequency too often
+                                resulting in performance loss.
 scaling_driver :                this file shows what cpufreq driver is
                                 used to set the frequency on this CPU
 
diff --git a/arch/x86/include/asm/timer.h b/arch/x86/include/asm/timer.h
index 2bb6a835c453..4f5c24724856 100644
--- a/arch/x86/include/asm/timer.h
+++ b/arch/x86/include/asm/timer.h
@@ -11,8 +11,8 @@ unsigned long native_calibrate_tsc(void);
 
 #ifdef CONFIG_X86_32
 extern int timer_ack;
+#endif
 extern int recalibrate_cpu_khz(void);
-#endif /* CONFIG_X86_32 */
 
 extern int no_timer_check;
 
diff --git a/arch/x86/kernel/cpu/cpufreq/Kconfig b/arch/x86/kernel/cpu/cpufreq/Kconfig
index 65792c2cc462..52c839875478 100644
--- a/arch/x86/kernel/cpu/cpufreq/Kconfig
+++ b/arch/x86/kernel/cpu/cpufreq/Kconfig
@@ -87,30 +87,15 @@ config X86_POWERNOW_K7_ACPI
 config X86_POWERNOW_K8
         tristate "AMD Opteron/Athlon64 PowerNow!"
         select CPU_FREQ_TABLE
+        depends on ACPI && ACPI_PROCESSOR
         help
-          This adds the CPUFreq driver for mobile AMD Opteron/Athlon64 processors.
+          This adds the CPUFreq driver for K8/K10 Opteron/Athlon64 processors.
 
           To compile this driver as a module, choose M here: the
           module will be called powernow-k8.
 
           For details, take a look at <file:Documentation/cpu-freq/>.
 
-          If in doubt, say N.
-
-config X86_POWERNOW_K8_ACPI
-        bool
-        prompt "ACPI Support" if X86_32
-        depends on ACPI && X86_POWERNOW_K8 && ACPI_PROCESSOR
-        depends on !(X86_POWERNOW_K8 = y && ACPI_PROCESSOR = m)
-        default y
-        help
-          This provides access to the K8s Processor Performance States via ACPI.
-          This driver is probably required for CPUFreq to work with multi-socket and
-          SMP systems.  It is not required on at least some single-socket yet
-          multi-core systems, even if SMP is enabled.
-
-          It is safe to say Y here.
-
 config X86_GX_SUSPMOD
         tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
         depends on X86_32 && PCI
diff --git a/arch/x86/kernel/cpu/cpufreq/Makefile b/arch/x86/kernel/cpu/cpufreq/Makefile
index 560f7760dae5..509296df294d 100644
--- a/arch/x86/kernel/cpu/cpufreq/Makefile
+++ b/arch/x86/kernel/cpu/cpufreq/Makefile
@@ -1,6 +1,11 @@
+# Link order matters. K8 is preferred to ACPI because of firmware bugs in early
+# K8 systems. ACPI is preferred to all other hardware-specific drivers.
+# speedstep-* is preferred over p4-clockmod.
+
+obj-$(CONFIG_X86_POWERNOW_K8)           += powernow-k8.o
+obj-$(CONFIG_X86_ACPI_CPUFREQ)          += acpi-cpufreq.o
 obj-$(CONFIG_X86_POWERNOW_K6)           += powernow-k6.o
 obj-$(CONFIG_X86_POWERNOW_K7)           += powernow-k7.o
-obj-$(CONFIG_X86_POWERNOW_K8)           += powernow-k8.o
 obj-$(CONFIG_X86_LONGHAUL)              += longhaul.o