[CPUFREQ] speedstep-centrino: skip extract_clock logic for acpi based centrino
speedstep_centrino.c:extract_clock() assumes the bus speed of 100MHz, which is
not true with latest laptops. Due to this assumption and due to the encoded
frequency check during initialization, speedstep-centrino driver fails even
on systems that has proper ACPI information to do the P-state transition.
The change below moves the centrino-speedstep detection to be used only
when table based P-state transition is done. For ACPI based P-state
transition, we skip the centrino_cpu identification, and as a result we
don't use the bus speed assumption in extract_clock. This change makes
speedstep-centrino work on Pentium-M based systems, which have more than 100MHz
bus speed.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
diff --git a/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c b/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
index 327a55d..95e15b7 100644
--- a/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
+++ b/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
@@ -498,13 +498,6 @@
if (cpu->x86_vendor != X86_VENDOR_INTEL || !cpu_has(cpu, X86_FEATURE_EST))
return -ENODEV;
- for (i = 0; i < N_IDS; i++)
- if (centrino_verify_cpu_id(cpu, &cpu_ids[i]))
- break;
-
- if (i != N_IDS)
- centrino_cpu[policy->cpu] = &cpu_ids[i];
-
if (is_const_loops_cpu(policy->cpu)) {
centrino_driver.flags |= CPUFREQ_CONST_LOOPS;
}
@@ -513,6 +506,13 @@
if (policy->cpu != 0)
return -ENODEV;
+ for (i = 0; i < N_IDS; i++)
+ if (centrino_verify_cpu_id(cpu, &cpu_ids[i]))
+ break;
+
+ if (i != N_IDS)
+ centrino_cpu[policy->cpu] = &cpu_ids[i];
+
if (!centrino_cpu[policy->cpu]) {
dprintk(KERN_INFO PFX "found unsupported CPU with "
"Enhanced SpeedStep: send /proc/cpuinfo to "
