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@xxxxxxx>
Cc: Langsdorf, Mark <mark.langsdorf@xxxxxxx>
Cc: Thomas Renninger <trenn@xxxxxxx>
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@xxxxxx>
Reviewed-by: Andreas Herrmann <andreas.herrmann3@xxxxxxx>
Tested-by: Andreas Herrmann <andreas.herrmann3@xxxxxxx>
Acked-by: Langsdorf, Mark <mark.langsdorf@xxxxxxx>
Signed-off-by: Thomas Renninger <trenn@xxxxxxx>
---
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 cf52215..700ede9 100644
--- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
@@ -117,20 +117,17 @@ 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 {
--
1.6.2.2
--
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