3.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dirk Brandewie <dirk.j.brandewie@xxxxxxxxx> commit c16ed06024a6e699c332831dd50d8276744e3de8 upstream. Commit 21855ff5 (intel_pstate: Set turbo VID for BayTrail) introduced setting the turbo VID which is required to prevent a machine check on some Baytrail SKUs under heavy graphics based workloads. The docmumentation update that brought the requirement to light also changed the bit mask used for enumerating P state and VID values from 0x7f to 0x3f. This change returns the mask value to 0x7f. Tested with the Intel NUC DN2820FYK, BIOS version FYBYT10H.86A.0034.2014.0513.1413 with v3.16-rc1 and v3.14.8 kernel versions. Fixes: 21855ff5 (intel_pstate: Set turbo VID for BayTrail) Link: https://bugzilla.kernel.org/show_bug.cgi?id=77951 Reported-and-tested-by: Rune Reterson <rune@xxxxxxxxxxxx> Reported-and-tested-by: Eric Eickmeyer <erich@xxxxxxxxxxxxxxxxxx> Signed-off-by: Dirk Brandewie <dirk.j.brandewie@xxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/cpufreq/intel_pstate.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -361,21 +361,21 @@ static int byt_get_min_pstate(void) { u64 value; rdmsrl(BYT_RATIOS, value); - return (value >> 8) & 0x3F; + return (value >> 8) & 0x7F; } static int byt_get_max_pstate(void) { u64 value; rdmsrl(BYT_RATIOS, value); - return (value >> 16) & 0x3F; + return (value >> 16) & 0x7F; } static int byt_get_turbo_pstate(void) { u64 value; rdmsrl(BYT_TURBO_RATIOS, value); - return value & 0x3F; + return value & 0x7F; } static void byt_set_pstate(struct cpudata *cpudata, int pstate) @@ -409,8 +409,8 @@ static void byt_get_vid(struct cpudata * rdmsrl(BYT_VIDS, value); - cpudata->vid.min = int_tofp((value >> 8) & 0x3f); - cpudata->vid.max = int_tofp((value >> 16) & 0x3f); + cpudata->vid.min = int_tofp((value >> 8) & 0x7f); + cpudata->vid.max = int_tofp((value >> 16) & 0x7f); cpudata->vid.ratio = div_fp( cpudata->vid.max - cpudata->vid.min, int_tofp(cpudata->pstate.max_pstate - -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html