[PATCH] hwmon: (coretemp) Fix TjMax for Atom N450/D410/D510 CPUs

Yong Wang
2009-12-24T07:34:41Z

The max junction temperature of Atom N450/D410/D510 CPUs is 100 degrees Celsius.
Since these CPUs are always coupled with Intel NM10 chipset in one package, the
best way to verify whether an Atom CPU is N450/D410/D510 is to check the host
bridge device.

Signed-off-by: Yong Wang <yong.y.wang@intel.com>
Acked-by: Huaxu Wan <huaxu.wan@intel.com>
---
drivers/hwmon/coretemp.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index caef39c..65a33ec 100644
--- a/drivers/hwmon/coretemp.c
+++ b/drivers/hwmon/coretemp.c
@@ -33,6 +33,7 @@
#include <linux/list.h>
#include <linux/platform_device.h>
#include <linux/cpu.h>
+#include <linux/pci.h>
#include <asm/msr.h>
#include <asm/processor.h>

@@ -161,6 +162,7 @@ static int __devinit adjust_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *
int usemsr_ee = 1;
int err;
u32 eax, edx;
+ struct pci_dev *host_bridge;

/* Early chips have no MSR for TjMax */

@@ -168,11 +170,21 @@ static int __devinit adjust_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *
usemsr_ee = 0;
}

- /* Atoms seems to have TjMax at 90C */
+ /* Atoms CPUs */

if (c->x86_model == 0x1c) {
usemsr_ee = 0;
- tjmax = 90000;
+
+ host_bridge = pci_get_bus_and_slot(0, PCI_DEVFN(0, 0));
+
+ if (host_bridge && host_bridge->vendor == PCI_VENDOR_ID_INTEL
+ && (host_bridge->device == 0xa000 /* NM10 based nettop */
+ || host_bridge->device == 0xa010)) /* NM10 based netbook */
+ tjmax = 100000;
+ else
+ tjmax = 90000;
+
+ pci_dev_put(host_bridge);
}

if ((c->x86_model > 0xe) && (usemsr_ee)) {