diff options
| author | Guenter Roeck <linux@roeck-us.net> | 2014-04-30 14:08:14 -0700 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2014-05-01 04:07:52 -0700 |
| commit | c0940e95f7a78be0525c8d31df0b1f71e149e57e (patch) | |
| tree | 777190e02b9990579f00b1d1281d85f98900cccc | |
| parent | d1db0eea852497762cab43b905b879dfcd3b8987 (diff) | |
Revert "hwmon: (coretemp) Refine TjMax detection"
This reverts commit 9fb6c9c73b11bef65ba80a362547fd116c1e1c9d.
Tjmax on some Intel CPUs is below 85 degrees C. One known example is
L5630 with Tjmax of 71 degrees C. There are other Xeon processors with
Tjmax of 70 or 80 degrees C. Also, the Intel IA32 System Programming
document states that the temperature target is in bits 23:16 of MSR 0x1a2
(MSR_TEMPERATURE_TARGET), which is 8 bits, not 7.
So even if turbostat uses similar checks to validate Tjmax, there is no
evidence that the checks are actually required. On the contrary, the
checks are known to cause problems and therefore need to be removed.
This fixes https://bugzilla.kernel.org/show_bug.cgi?id=75071.
Fixes: 9fb6c9c hwmon: (coretemp) Refine TjMax detection
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Cc: stable@vger.kernel.org # 3.14+
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
| -rw-r--r-- | drivers/hwmon/coretemp.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c index 6d02e3b06375..d76f0b70c6e0 100644 --- a/drivers/hwmon/coretemp.c +++ b/drivers/hwmon/coretemp.c @@ -365,12 +365,12 @@ static int get_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev) if (cpu_has_tjmax(c)) dev_warn(dev, "Unable to read TjMax from CPU %u\n", id); } else { - val = (eax >> 16) & 0x7f; + val = (eax >> 16) & 0xff; /* * If the TjMax is not plausible, an assumption * will be used */ - if (val >= 85) { + if (val) { dev_dbg(dev, "TjMax is %d degrees C\n", val); return val * 1000; } |