On Thu, 2025-09-25 at 10:40 -0600, Jerry Hoemann wrote:
> Processor TControl Information
>
> Signed-off-by: Jerry Hoemann <[email protected]>
> ---
> dmioem.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 48 insertions(+)
>
> diff --git a/dmioem.c b/dmioem.c
> index 4fa616b..051fd09 100644
> --- a/dmioem.c
> +++ b/dmioem.c
> @@ -1428,6 +1428,54 @@ static int dmi_decode_hp(const struct dmi_header *h)
> }
> break;
>
> + case 211:
> + /*
> + * Vendor Specific: HPE ProLiant Processor TControl
> Information
> + *
> + * Provides information about the Tcontrol value for
> each installed
> + * processor. This information is utilized to optimize
> the thermal fan
> + * control systems on the system. For some systems,
> this can be handled
> + * totally by the System ROM (systems with 7463 fan
> controllers). For
> + * systems that utilize TAFI, the Health Driver handles
> fan control.
> + * The Health Driver must know the value for Tcontrol
> for all processors
> + * to be able to customize the fan control for the
> installed processors.
> + *
> + * Tcontrol is a value programmed into each processor
> by Intel that
> + * indicates the processors thermal properties. The
> value is based on
> + * how "leaky" the particular processor's transistors
> are. A more "leaky"
> + * processor will get hotter for a given power input
> and thus will have a
> + * higher Tcontrol value. Intel officially suggests
> keeping a processor
> + * below the Tcontrol value for reliability reasons. HP
> is using Tcontrol
> + * as the point at which we begin spinning up the fans.
> + *
> + * Software must check the corresponding Record Type 4
> to determine if the
> + * processor is installed. If the processor is not
> installed, the
> + * corresponding Record Type 211 should not be
> utilized. Record Type 197
> + * must be used to correlate Type 211 Record to the
> processor's APIC ID.
> + * This must be done to know which TAFI controller must
> be programmed with
> + * a particular Tcontrol value. Type 197 Record has an
> identifier which
> + * relates it to a Type 4 Record, so it is possible to
> correlate a
> + * Type 211 Record with a Type 197 Record.
> + *
> + * Offset | Name | Width | Description
> + * -------------------------------------
> + * 0x00 | Type | BYTE | 0xD3, TConrol Info
> + * 0x01 | Length | BYTE | Length of structure
> + * 0x02 | Handle | WORD | Unique handle
> + * 0x04 | Handle | WORD | Handle of Cooresponding
> Type 4 Proc Record
Spelling: corresponding.
I'd also suggest writing "processor" instead of "proc" for clarity.
> + * 0x06 |Tcontrol| BYTE | Processor Tcontrol Value.
> 00 -> Value N/A.
> + */
> +
> + pr_handle_name("%s ProLiant TControl Information",
> company);
> + if (h->length < 0x07) break;
> + if (!(opt.flags & FLAG_QUIET))
> + pr_attr("Associated Handle", "0x%04X",
> WORD(data + 0x8));
0x8 may be (will be) beyond the end of the record. I think you meant
0x04.
> + if (data[0x06])
> + pr_attr("TControl Value", "%d", data[0x06]);
> + else
> + pr_attr("TControl Value", "%s", "N/A");
> + break;
> +
> case 212:
> /*
> * Vendor Specific: HPE 64-bit CRU Information
Looks simple enough, but surprisingly some samples in my collection
have unexpectedly low Tcontrol values (8, 10, 18).
--
Jean Delvare
SUSE L3 Support
