aha/arch/x86
Andreas Herrmann ca446d0635 [CPUFREQ] powernow-k8: determine exact CPU frequency for HW Pstates
Slightly modified by trenn@suse.de -> only do this on fam 10h and fam 11h.

Currently powernow-k8 determines CPU frequency from ACPI PSS objects, but
according to AMD family 11h BKDG this frequency is just a rounded value:

  "CoreFreq (MHz) = The CPU COF specified by MSRC001_00[6B:64][CpuFid]
  rounded to the nearest 100 Mhz."

As a consequnce powernow-k8 reports wrong CPU frequency on some systems,
e.g. on Turion X2 Ultra:

  powernow-k8: Found 1 AMD Turion(tm)X2 Ultra DualCore Mobile ZM-82
               processors (2 cpu cores) (version 2.20.00)
  powernow-k8:    0 : pstate 0 (2200 MHz)
  powernow-k8:    1 : pstate 1 (1100 MHz)
  powernow-k8:    2 : pstate 2 (600 MHz)

But this is wrong as frequency for Pstate2 is 550 MHz. x86info reports it
correctly:

  #x86info -a |grep Pstate
  ...
  Pstate-0: fid=e, did=0, vid=24 (2200MHz)
  Pstate-1: fid=e, did=1, vid=30 (1100MHz)
  Pstate-2: fid=e, did=2, vid=3c (550MHz) (current)

Solution is to determine the frequency directly from Pstate MSRs instead
of using rounded values from ACPI table.

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-05-26 12:04:51 -04:00
..
boot x86, setup: revert ACPI 3 E820 extended attributes support 2009-05-22 11:14:02 -07:00
configs Merge branches 'x86/apic', 'x86/defconfig', 'x86/memtest', 'x86/mm' and 'linus' into x86/core 2009-02-26 06:31:32 +01:00
crypto crypto: aes-ni - Add support to Intel AES-NI instructions for x86_64 platform 2009-02-18 16:48:06 +08:00
ia32 Separate out common fstatat code into vfs_fstatat 2009-04-20 23:02:51 -04:00
include/asm x86: Fix performance regression caused by paravirt_ops on native kernels 2009-05-15 20:07:42 +02:00
kernel [CPUFREQ] powernow-k8: determine exact CPU frequency for HW Pstates 2009-05-26 12:04:51 -04:00
kvm KVM: Fix PDPTR reloading on CR4 writes 2009-05-25 20:00:53 +03:00
lguest clocksource: pass clocksource to read() callback 2009-04-21 13:41:47 -07:00
lib x86: memcpy, clean up 2009-03-12 12:21:17 +01:00
math-emu Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2 2009-03-27 17:28:43 +01:00
mm x86: cpa_flush_array wbinvd should be done on all CPUs 2009-05-22 13:33:59 -07:00
oprofile x86, 32-bit: fix kernel_trap_sp() 2009-05-12 00:39:52 +02:00
pci x86/PCI: don't bother with root quirks if _CRS is used 2009-04-22 15:06:29 -07:00
power x86: disable stack-protector for __restore_processor_state() 2009-04-03 19:48:41 +02:00
vdso x86: gettimeofday() vDSO: fix segfault when tv == NULL 2009-04-30 12:31:45 +02:00
video
xen x86: Fix performance regression caused by paravirt_ops on native kernels 2009-05-15 20:07:42 +02:00
Kconfig x86: Fix performance regression caused by paravirt_ops on native kernels 2009-05-15 20:07:42 +02:00
Kconfig.cpu x86: disable X86_PTRACE_BTS for now 2009-04-15 23:15:14 +02:00
Kconfig.debug generic debug pagealloc: build fix 2009-04-02 19:04:48 -07:00
Makefile x86, kbuild: make "make install" not depend on vmlinux 2009-04-17 22:43:12 +02:00
Makefile_32.cpu