Re: [lm-sensors] [PATCH 1/2] hwmon: (coretemp) Detect the thermalsensors by CPUID

From: Huaxu Wan
Date: Sun May 09 2010 - 22:26:11 EST


On 15:21 Fri 07 May, Carsten Emde wrote:
> Hi Huaxu,
>
> > The thermal sensors of Intel(R) CPUs can be detected by CPUID instruction,
> > indicated by CPUID.06H.EAX[0].
> Thanks, works great, successfully tested it on an i7 machine.
>
> I would propose to use dev_warn() instead of printk_once(), since all
> other per-cpu info is also logged this way.
>
> Signed-off-by: Carsten Emde <C.Emde@xxxxxxxxx>
>

That reminds me that dev_warn is right one on multiple CPU system, especially with different CPUs. Thank you.

> ---
> drivers/hwmon/coretemp.c | 23 +++++++----------------
> 1 file changed, 7 insertions(+), 16 deletions(-)
>
> Index: head/drivers/hwmon/coretemp.c
> ===================================================================
> --- head.orig/drivers/hwmon/coretemp.c
> +++ head/drivers/hwmon/coretemp.c
> @@ -440,6 +440,7 @@ static int __init coretemp_init(void)
> {
> int i, err = -ENODEV;
> struct pdev_entry *p, *n;
> + u32 eax;
>
> /* quick check if we run Intel */
> if (cpu_data(0).x86_vendor != X86_VENDOR_INTEL)
> @@ -450,23 +451,13 @@ static int __init coretemp_init(void)
> goto exit;
>
> for_each_online_cpu(i) {
> - struct cpuinfo_x86 *c = &cpu_data(i);
> + /* check if the CPU has thermal sensor */
> + eax = cpuid_eax(0x06);
> + if (!(eax & 0x01)) {
> + struct cpuinfo_x86 *c = &cpu_data(i);
>
> - /* check if family 6, models 0xe (Pentium M DC),
> - 0xf (Core 2 DC 65nm), 0x16 (Core 2 SC 65nm),
> - 0x17 (Penryn 45nm), 0x1a (Nehalem), 0x1c (Atom),
> - 0x1e (Lynnfield) */
> - if ((c->cpuid_level < 0) || (c->x86 != 0x6) ||
> - !((c->x86_model == 0xe) || (c->x86_model == 0xf) ||
> - (c->x86_model == 0x16) || (c->x86_model == 0x17) ||
> - (c->x86_model == 0x1a) || (c->x86_model == 0x1c) ||
> - (c->x86_model == 0x1e))) {
> -
> - /* supported CPU not found, but report the unknown
> - family 6 CPU */
> - if ((c->x86 == 0x6) && (c->x86_model > 0xf))
> - printk(KERN_WARNING DRVNAME ": Unknown CPU "
> - "model 0x%x\n", c->x86_model);
> + dev_warn("CPU (model=0x%x) has no thermal sensor!\n",
> + c->x86_model);
> continue;
> }
>


--
Thanks
Huaxu
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/