diff options
| author | Naga Chumbalkar <nagananda.chumbalkar@hp.com> | 2009-06-11 15:26:48 +0000 |
|---|---|---|
| committer | Dave Jones <davej@redhat.com> | 2009-06-15 11:49:42 -0400 |
| commit | 532cfee6ba0a8efcf7c3ce38b9881292d79d516e (patch) | |
| tree | f27ca50e349d890aa5853cc0a5ca49d8e6a5e116 /arch/x86 | |
| parent | b394f1dfc070e6f50f5f33694000815e50ef319d (diff) | |
[CPUFREQ] powernow-k8: read P-state from HW
By definition, "cpuinfo_cur_freq" should report the value from HW. So, don't
depend on the cached value. Instead read P-state directly from HW, while
taking into account the erratum 311 workaround for Fam 11h processors.
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Langsdorf, Mark <mark.langsdorf@amd.com>
Cc: Thomas Renninger <trenn@suse.de>
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Reviewed-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Langsdorf, Mark <mark.langsdorf@amd.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/cpu/cpufreq/powernow-k8.c | 25 |
1 files changed, 11 insertions, 14 deletions
diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c index 2709b3c183b..331021112f2 100644 --- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c +++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c @@ -118,20 +118,17 @@ static int query_current_values_with_pending_wait(struct powernow_k8_data *data) u32 i = 0; if (cpu_family == CPU_HW_PSTATE) { - if (data->currpstate == HW_PSTATE_INVALID) { - /* read (initial) hw pstate if not yet set */ - rdmsr(MSR_PSTATE_STATUS, lo, hi); - i = lo & HW_PSTATE_MASK; - - /* - * a workaround for family 11h erratum 311 might cause - * an "out-of-range Pstate if the core is in Pstate-0 - */ - if (i >= data->numps) - data->currpstate = HW_PSTATE_0; - else - data->currpstate = i; - } + rdmsr(MSR_PSTATE_STATUS, lo, hi); + i = lo & HW_PSTATE_MASK; + data->currpstate = i; + + /* + * a workaround for family 11h erratum 311 might cause + * an "out-of-range Pstate if the core is in Pstate-0 + */ + if ((boot_cpu_data.x86 == 0x11) && (i >= data->numps)) + data->currpstate = HW_PSTATE_0; + return 0; } do { |