diff options
| -rw-r--r-- | sys/x86/cpufreq/est.c | 7 |
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); } |
