Re: [PATCH] cpufreq/amd-pstate: Supply nominal/lowest freq for TRX40-based motherboards

[Mario Limonciello <mario.limonciello@amd.com>]

OK, let's wait and see what happens after you upgrade.  New versions of 
FW and the behavior please.

On 10/7/26 12:43, Kyle Gospodnetich wrote:
> Missed one,
> 
> Release Date: 05/17/2022
> 
> 
> On Wednesday, October 7th, 2026 at 10:36 AM, Kyle Gospodnetich <me@kylegospodneti.ch> wrote:
> 
>> AMD Ryzen Threadripper 3960X
>> MSI TRX40-PRO-10G
>> https://www.msi.com/Motherboard/TRX40-PRO-10G/support
>> I am using 7C60v1A3(Beta version), I will update to the latest today -- just learning that exists.
>> dmidecode reports that as:
>> Vendor: American Megatrends International, LLC.
>> Version: 1.80
>>
>> I've had to disable pstate with:
>> amd_pstate.enable=0 initcall_blacklist=amd-pstate
>>
>> Without that my system grinds to a hault, takes upwards of 15 minutes just to hit the desktop.
>>
>> Thanks, let me know if anything else is needed.
>> -Kyle Gospodnetich
>>
>>
>> On Wednesday, October 7th, 2026 at 8:06 AM, Mario Limonciello <mario.limonciello@amd.com> wrote:
>>
>>> Kyle,
>>>
>>> Can you please confirm more about your system?  System Model, vendor,
>>> BIOS version, BIOS vendor, CPU model.
>>>
>>> Thanks,
>>>
>>> On 10/7/26 10:04, Kyle Gospodnetich wrote:
>>>> Yes this does appear to be the same problem, thank you!
>>>>
>>>> -------- Original Message --------
>>>> On Wednesday, 10/07/26 at 07:56 Mario Limonciello <mario.limonciello@amd.com> wrote:
>>>> + Kyle
>>>>
>>>> Kyle,
>>>>
>>>> By chance is this the same system that you were talking to me about offline?
>>>>
>>>>
>>>>
>>>> On 10/7/26 09:41, Giovanni Gherdovich wrote:
>>>>> Some motherboard based on the TRX40 chipset has been reported to ship
>>>>> firmware lacking lowest and nominal frequency values in the
>>>>> _CPC ACPI package. That is, it supports CPPC V2 but not CPPC V3.
>>>>> Firmware updates aren't available.
>>>>
>>>> Can you please add more information about the vendor/model of the MB, etc?
>>>>>
>>>>> amd-pstate requires explicit knowledge of nominal frequency, so it
>>>>> can't load on this hardware. The driver already has a mechanism (the
>>>>> so-called "quirks") to accommodate for missing nominal freq in ACPI
>>>>> tables, so here we use it to match against CPU family, model, core
>>>>> count, and BIOS version.
>>>>
>>>> Yeah; it's intended for this specific case of really old hardware that
>>>> the BIOS isn't going to fix it.
>>>>
>>>> I don't understand why core count matters though.
>>>>
>>>>>
>>>>> Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
>>>>> ---
>>>>>     drivers/cpufreq/amd-pstate.c | 31 +++++++++++++++++++++++++++++++
>>>>>     1 file changed, 31 insertions(+)
>>>>>
>>>>> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
>>>>> index 8bfd46d60843..532ff16dd076 100644
>>>>> --- a/drivers/cpufreq/amd-pstate.c
>>>>> +++ b/drivers/cpufreq/amd-pstate.c
>>>>> @@ -145,6 +145,11 @@ static struct quirk_entry quirk_amd_7k62 = {
>>>>>     	.lowest_freq = 550,
>>>>>     };
>>>>>
>>>>> +static struct quirk_entry quirk_amd_ryzen_threadripper_3000_24c = {
>>>>> +	.nominal_freq = 3800,
>>>>> +	.lowest_freq = 550,
>>>>> +};
>>>>> +
>>>>>     static inline u8 freq_to_perf(union perf_cached perf, u32 nominal_freq, unsigned int freq_val)
>>>>>     {
>>>>>     	u32 perf_val = DIV_ROUND_UP_ULL((u64)freq_val * perf.nominal_perf, nominal_freq);
>>>>> @@ -174,6 +179,22 @@ static int __init dmi_matched_7k62_bios_bug(const struct dmi_system_id *dmi)
>>>>>     	return 0;
>>>>>     }
>>>>>
>>>>> +static int __init dmi_matched_trx40_bios_bug(const struct dmi_system_id *dmi)
>>>>> +{
>>>>> +	/**
>>>>> +	 * Match the Ryzen Threadripper 3000 series, 24-core SKU, sTRX4 socket / TRX40 chipset.
>>>>> +	 */
>>>>> +	if (boot_cpu_data.x86 == 0x17 &&
>>>>> +	    boot_cpu_data.x86_model >= 0x30 && boot_cpu_data.x86_model <= 0x3F &&
>>>>> +	    topology_num_cores_per_package() == 24) {
>>>>
>>>> Does the number of cores actually matter?  Do you mean to say if you
>>>> swap the CPU to another part CPPC works?
>>>>
>>>>> +		quirks = dmi->driver_data;
>>>>> +		pr_info("Overriding nominal and lowest frequencies for %s\n", dmi->ident);
>>>>
>>>> The BIOS bug specifically is lack of values, not invalid values, right?
>>>> Just want to make sure I'm following this right.
>>>>
>>>>> +		return 1;
>>>>> +	}
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>>     static const struct dmi_system_id amd_pstate_quirks_table[] __initconst = {
>>>>>     	{
>>>>>     		.callback = dmi_matched_7k62_bios_bug,
>>>>> @@ -184,6 +205,16 @@ static const struct dmi_system_id amd_pstate_quirks_table[] __initconst = {
>>>>>     		},
>>>>>     		.driver_data = &quirk_amd_7k62,
>>>>>     	},
>>>>> +	{
>>>>> +		.callback = dmi_matched_trx40_bios_bug,
>>>>> +		.ident = "AMD Ryzen Threadripper 3000",
>>>>> +		.matches = {
>>>>> +			DMI_MATCH(DMI_BIOS_VENDOR,  "American Megatrends International"),
>>>>> +			DMI_MATCH(DMI_BIOS_VERSION, "2.80"),
>>>>> +			DMI_MATCH(DMI_BIOS_DATE,    "05/17/2022"),
>>>>> +		},
>>>>> +		.driver_data = &quirk_amd_ryzen_threadripper_3000_24c,
>>>>> +	},
>>>>>     	{}
>>>>>     };
>>>>>     MODULE_DEVICE_TABLE(dmi, amd_pstate_quirks_table);
>>>>
>>>
>>>