summaryrefslogtreecommitdiffstats
path: root/sys/x86
diff options
context:
space:
mode:
Diffstat (limited to 'sys/x86')
-rw-r--r--sys/x86/cpufreq/est.c7
1 files changed, 5 insertions, 2 deletions
diff --git a/sys/x86/cpufreq/est.c b/sys/x86/cpufreq/est.c
index ecca30c..678efb6 100644
--- a/sys/x86/cpufreq/est.c
+++ b/sys/x86/cpufreq/est.c
@@ -947,8 +947,11 @@ static int
est_features(driver_t *driver, u_int *features)
{
- /* Notify the ACPI CPU that we support direct access to MSRs */
- *features = ACPI_CAP_PERF_MSRS;
+ /*
+ * Notify the ACPI CPU that we support direct access to MSRs.
+ * XXX C1 "I/O then Halt" seems necessary for some broken BIOS.
+ */
+ *features = ACPI_CAP_PERF_MSRS | ACPI_CAP_C1_IO_HALT;
return (0);
}
OpenPOWER on IntegriCloud