hwmon: (coretemp) Drop dependency on PCI for TjMax detection on Atom CPUs
So far, we use the NM10 Express Chipset PCI chip ID to detect TjMax for
Atom CPUs with model 0x1c. As it turns out, we can use the CPU stepping
(x86_mask) for the same purpose; stepping is 10 for all model 0x1c CPUs
with TjMax of 100 degrees C. This was verified by checking the output of
/proc/cpuinfo for the respective CPUs (D4xx, D5xx, N4xx, N5xx).
Other CPUs currently covered by the same code (Exx, Z6xx, Z2460) are not
supported by the NM10 Express Chipset. Most of those CPUs have TjMax of 90
degrees C, except for E6xxT models which have a TjMax of 110 degrees C.
E6xxT CPUs can however not be detected by software.
Calculate TjMax for Atom CPUs as follows. Note that the listed values are not
correct in some cases (230, 330). tjmax_table is used for those to override
the default values.
ID Stepping TjMax Models
0x1c 10 100 D4xx, N4xx, D5xx, N5xx
0x1c not 10 90 Z5xx, N2xx, 230, 330, others
0x26 - 90 Atom Tunnel Creek (Exx),
Lincroft (Z6xx)
0x27 - 90 Atom Medfield (Z2460)
0x36 - 100 Atom Cedar Trail (N2xxx, D2xxx)
Also drop the module dependency on PCI.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Jean Delvare <khali@linux-fr.org>
2 files changed