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authorLinus Torvalds <torvalds@linux-foundation.org>2009-04-05 11:16:25 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-04-05 11:16:25 -0700
commit32fb6c17566ec66de87324a834c7776f40e35e78 (patch)
tree87b8ed5d66495536fbb452255c3eacd1cfb0c43a /arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
parent45e36c1666aa6c8b0c538abcf984b336184d8c3f (diff)
parent7ec0a7290797f57b780f792d12f4bcc19c83aa4f (diff)
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (140 commits) ACPI: processor: use .notify method instead of installing handler directly ACPI: button: use .notify method instead of installing handler directly ACPI: support acpi_device_ops .notify methods toshiba-acpi: remove MAINTAINERS entry ACPI: battery: asynchronous init acer-wmi: Update copyright notice & documentation acer-wmi: Cleanup the failure cleanup handling acer-wmi: Blacklist Acer Aspire One video: build fix thinkpad-acpi: rework brightness support thinkpad-acpi: enhanced debugging messages for the fan subdriver thinkpad-acpi: enhanced debugging messages for the hotkey subdriver thinkpad-acpi: enhanced debugging messages for rfkill subdrivers thinkpad-acpi: restrict access to some firmware LEDs thinkpad-acpi: remove HKEY disable functionality thinkpad-acpi: add new debug helpers and warn of deprecated atts thinkpad-acpi: add missing log levels thinkpad-acpi: cleanup debug helpers thinkpad-acpi: documentation cleanup thinkpad-acpi: drop ibm-acpi alias ...
Diffstat (limited to 'arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c')
-rw-r--r--arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
index 05209b5cc6ca..19f6b9d27e83 100644
--- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
+++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
@@ -682,6 +682,18 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
perf->states[i].transition_latency * 1000;
}
+ /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
+ if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
+ policy->cpuinfo.transition_latency > 20 * 1000) {
+ static int print_once;
+ policy->cpuinfo.transition_latency = 20 * 1000;
+ if (!print_once) {
+ print_once = 1;
+ printk(KERN_INFO "Capping off P-state tranision latency"
+ " at 20 uS\n");
+ }
+ }
+
data->max_freq = perf->states[0].core_frequency * 1000;
/* table init */
for (i = 0; i < perf->state_count; i++) {