1. 25 11月, 2009 5 次提交
    • T
      [ACPI/CPUFREQ] Introduce bios_limit per cpu cpufreq sysfs interface · e2f74f35
      Thomas Renninger 提交于
      This interface is mainly intended (and implemented) for ACPI _PPC BIOS
      frequency limitations, but other cpufreq drivers can also use it for
      similar use-cases.
      
      Why is this needed:
      
      Currently it's not obvious why cpufreq got limited.
      People see cpufreq/scaling_max_freq reduced, but this could have
      happened by:
        - any userspace prog writing to scaling_max_freq
        - thermal limitations
        - hardware (_PPC in ACPI case) limitiations
      
      Therefore export bios_limit (in kHz) to:
        - Point the user that it's the BIOS (broken or intended) which limits
          frequency
        - Export it as a sysfs interface for userspace progs.
          While this was a rarely used feature on laptops, there will appear
          more and more server implemenations providing "Green IT" features like
          allowing the service processor to limit the frequency. People want
          to know about HW/BIOS frequency limitations.
      
      All ACPI P-state driven cpufreq drivers are covered with this patch:
        - powernow-k8
        - powernow-k7
        - acpi-cpufreq
      
      Tested with a patched DSDT which limits the first two cores (_PPC returns 1)
      via _PPC, exposed by bios_limit:
      # echo 2200000 >cpu2/cpufreq/scaling_max_freq
      # cat cpu*/cpufreq/scaling_max_freq
      2600000
      2600000
      2200000
      2200000
      # #scaling_max_freq shows general user/thermal/BIOS limitations
      
      # cat cpu*/cpufreq/bios_limit
      2600000
      2600000
      2800000
      2800000
      # #bios_limit only shows the HW/BIOS limitation
      
      CC: Pallipadi Venkatesh <venkatesh.pallipadi@intel.com>
      CC: Len Brown <lenb@kernel.org>
      CC: davej@codemonkey.org.uk
      CC: linux@dominikbrodowski.net
      Signed-off-by: NThomas Renninger <trenn@suse.de>
      Signed-off-by: NDave Jones <davej@redhat.com>
      e2f74f35
    • R
      [CPUFREQ] use an enum for speedstep processor identification · 1cce76c2
      Rusty Russell 提交于
      The "unsigned int processor" everywhere confused Rusty, leading to
      breakage when he passed in smp_processor_id().
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      Acked-by: NDominik Brodowski <linux@dominikbrodowski.net>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NDave Jones <davej@redhat.com>
      1cce76c2
    • K
      [CPUFREQ] powernow-k6: set transition latency value so ondemand governor can be used · db2820dd
      Krzysztof Helt 提交于
      Set the transition latency to value smaller than CPUFREQ_ETERNAL so
      governors other than "performance" work (like the "ondemand" one).
      
      The value is found in "AMD PowerNow! Technology Platform Design Guide for
      Embedded Processors" dated December 2000 (AMD doc #24267A). There is the
      answer to one of FAQs on page 40 which states that suggested complete transition
      period is 200 us.
      
      Tested on K6-2+ CPU with K6-3 core (model 13, stepping 4).
      Signed-off-by: NKrzysztof Helt <krzysztof.h1@wp.pl>
      Signed-off-by: NDave Jones <davej@redhat.com>
      db2820dd
    • R
      [CPUFREQ] cpumask: don't put a cpumask on the stack in x86...cpufreq/powernow-k8.c · b8cbe7e8
      Rusty Russell 提交于
      It's still mugging the current process's cpumask, but as comment in
      1ff6e97f says, it's not a trivial fix.
      
      So, at least we can use a cpumask_var_t to do the Wrong Thing the Right Way :)
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      To: cpufreq@vger.kernel.org
      Cc: Mark Langsdorf <mark.langsdorf@amd.com>
      Signed-off-by: NDave Jones <davej@redhat.com>
      b8cbe7e8
    • H
      [CPUFREQ] Enable ACPI PDC handshake for VIA/Centaur CPUs · d77b8197
      Harald Welte 提交于
      In commit 0de51088, we introduced the
      use of acpi-cpufreq on VIA/Centaur CPU's by removing a vendor check for
      VENDOR_INTEL.  However, as it turns out, at least the Nano CPU's also
      need the PDC (processor driver capabilities) handshake in order to
      activate the methods required for acpi-cpufreq.
      
      Since arch_acpi_processor_init_pdc() contains another vendor check for
      Intel, the PDC is not initialized on VIA CPU's.  The resulting behavior
      of a current mainline kernel on such systems is:  acpi-cpufreq
      loads and it indicates CPU frequency changes.  However, the CPU stays at
      a single frequency
      
      This trivial patch ensures that init_intel_pdc() is called on Intel and
      VIA/Centaur CPU's alike.
      Signed-off-by: NHarald Welte <HaraldWelte@viatech.com>
      Signed-off-by: NDave Jones <davej@redhat.com>
      d77b8197
  2. 19 11月, 2009 2 次提交
  3. 18 11月, 2009 8 次提交
  4. 17 11月, 2009 4 次提交
  5. 16 11月, 2009 4 次提交
  6. 14 11月, 2009 6 次提交
  7. 13 11月, 2009 6 次提交
  8. 12 11月, 2009 5 次提交