diff options
| author | Dirk Brandewie <dirk.j.brandewie@intel.com> | 2014-06-20 07:27:58 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-07-17 16:21:05 -0700 |
| commit | 313b12ee56c99a9bc3809a9fa6968a2e9b69ca53 (patch) | |
| tree | 47ce0d71e53bec068004a71f9ffdddd8ac1a3273 | |
| parent | 5632b7dac85ab102c4b6efae57e41e8c71f84649 (diff) | |
intel_pstate: Fix setting VID
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@megahurts.dk>
Reported-and-tested-by: Eric Eickmeyer <erich@ericheickmeyer.com>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/cpufreq/intel_pstate.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 6d98c37c87a..149ac2567ae 100644 --- 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 *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 - |