[CPUFREQ] NVidia nForce2 FSB cpufreq driver.

Adds cpufreq support for FSB changing on nForce2 platforms.  On this
plattforms the PCI/AGP clock is independent from the FSB and it also
doesn't depend on the used CPU.

From: Sebastian Witt <se.witt@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dave Jones <davej@redhat.com>

Documentation/cpu-freq/cpufreq-nforce2.txt

+
+The cpufreq-nforce2 driver changes the FSB on nVidia nForce2 plattforms.
+
+This works better than on other plattforms, because the FSB of the CPU
+can be controlled independently from the PCI/AGP clock.
+
+The module has two options:
+
+	fid: 	 multiplier * 10 (for example 8.5 = 85)
+	min_fsb: minimum FSB
+
+If not set, fid is calculated from the current CPU speed and the FSB.
+min_fsb defaults to FSB at boot time - 50 MHz.
+
+IMPORTANT: The available range is limited downwards!
+           Also the minimum available FSB can differ, for systems 
+           booting with 200 MHz, 150 should always work.
+
+

arch/i386/kernel/cpu/cpufreq/Kconfig

@@ -170,6 +170,17 @@ config X86_P4_CLOCKMOD
 
 	  If in doubt, say N.
 
+config X86_CPUFREQ_NFORCE2
+	tristate "nVidia nForce2 FSB changing"
+	depends on CPU_FREQ && EXPERIMENTAL
+	help
+	  This adds the CPUFreq driver for FSB changing on nVidia nForce2
+	  plattforms.
+
+	  For details, take a look at <file:Documentation/cpu-freq/>.
+
+	  If in doubt, say N.
+
 config X86_LONGRUN
 	tristate "Transmeta LongRun"
 	depends on CPU_FREQ

arch/i386/kernel/cpu/cpufreq/Makefile

@@ -11,3 +11,4 @@ obj-$(CONFIG_X86_SPEEDSTEP_LIB) += speedstep-lib.o
 obj-$(CONFIG_X86_SPEEDSTEP_SMI)		+= speedstep-smi.o
 obj-$(CONFIG_X86_ACPI_CPUFREQ)		+= acpi-cpufreq.o
 obj-$(CONFIG_X86_P4_CLOCKMOD)		+= p4-clockmod.o
+obj-$(CONFIG_X86_CPUFREQ_NFORCE2)	+= cpufreq-nforce2.o