From 9fb6c9c73b11bef65ba80a362547fd116c1e1c9d Mon Sep 17 00:00:00 2001
From: Guenter Roeck <linux@roeck-us.net>
Date: Sat, 9 Nov 2013 09:38:14 -0800
Subject: [PATCH] hwmon: (coretemp) Refine TjMax detection
Intel's turbostat code uses only 7 bits from MSR_IA32_TEMPERATURE_TARGET to
read TjMax, and also only accepts it if the reported temperature is at least
85 degrees C. Play safe and do the same.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
drivers/hwmon/coretemp.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index 7eed10e20b38..b2e59b395ce4 100644
--- a/drivers/hwmon/coretemp.c
+++ b/drivers/hwmon/coretemp.c
@@ -368,12 +368,12 @@ 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) & 0xff;
+ val = (eax >> 16) & 0x7f;
/*
* If the TjMax is not plausible, an assumption
* will be used
*/
- if (val) {
+ if (val >= 85) {
dev_dbg(dev, "TjMax is %d degrees C\n", val);
return val * 1000;
}
--
2.20.1