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

[Kyle Gospodnetich]

Missed one,

Release Date: 05/17/2022


On Wednesday, October 7th, 2026 at 10:36 AM, Kyle Gospodnetich <me@xxxxxxxxxxxxxxxxx> 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@xxxxxxx> 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@xxxxxxx> 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@xxxxxxx>
> > >> ---
> > >>    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);
> > >
> >
> >