From: Mario Limonciello <mario.limonciello@amd.com>
To: Perry Yuan <perry.yuan@amd.com>,
rafael.j.wysocki@intel.com, viresh.kumar@linaro.org,
Ray.Huang@amd.com, gautham.shenoy@amd.com,
Borislav.Petkov@amd.com
Cc: Alexander.Deucher@amd.com, Xinmei.Huang@amd.com,
Xiaojian.Du@amd.com, Li.Meng@amd.com, linux-pm@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 6/6] cpufreq:amd-pstate: add quirk for the pstate CPPC capabilities missing
Date: Wed, 31 Jan 2024 15:59:32 -0600 [thread overview]
Message-ID: <49825045-bce1-4772-b7c4-2e116e19cbaf@amd.com> (raw)
In-Reply-To: <ab45b5a29507460a63d772a0e4b24b83c9b61aa6.1706690577.git.perry.yuan@amd.com>
On 1/31/2024 02:50, Perry Yuan wrote:
> Add quirk table to get CPPC capabilities issue fixed by providing
> correct perf or frequency values while driver loading.
>
> If CPPC capabilities are not defined in the ACPI tables or wrongly
> defined by platform firmware, it needs to use quick to get those
s/quick/quirk/
> issues fixed with correct workaround values to make pstate driver
to allow the pstate driver
> can be loaded even though there are CPPC capabilities errors.
>
> Signed-off-by: Perry Yuan <perry.yuan@amd.com>
> ---
> drivers/cpufreq/amd-pstate.c | 51 +++++++++++++++++++++++++++++++-----
> include/linux/amd-pstate.h | 6 +++++
> 2 files changed, 51 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index eea2e192d748..cbc415af0f08 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -64,6 +64,7 @@ static struct cpufreq_driver amd_pstate_driver;
> static struct cpufreq_driver amd_pstate_epp_driver;
> static int cppc_state = AMD_PSTATE_UNDEFINED;
> static bool cppc_enabled;
> +static struct quirk_entry *quirks;
>
> /**
> * struct global_params - Global parameters, mostly tunable via sysfs.
> @@ -121,6 +122,32 @@ static unsigned int epp_values[] = {
>
> typedef int (*cppc_mode_transition_fn)(int);
>
> +static struct quirk_entry quirk_amd_7k62 = {
> + .nominal_freq = 2600,
> + .lowest_freq = 550,
> +};
> +
> +static int __init dmi_matched(const struct dmi_system_id *dmi)
> +{
> + quirks = dmi->driver_data; > +
Under the presumption that the quirk list will grow as more buggy older
machines are identified, maybe it's worth having a dyndbg or info
statement here to indicate that it's using quirked values for dmi->ident.
> + return 1;
> +}
> +
> +static const struct dmi_system_id amd_pstate_quirks_table[] __initconst = {
> + {
> + .callback = dmi_matched,
> + .ident = "AMD EPYC 7K62",
> + .matches = {
> + DMI_MATCH(DMI_PRODUCT_VERSION, "C1"),
> + DMI_MATCH(DMI_PRODUCT_SERIAL, "FX19911000028"),
This is way too specific isn't it? It would only load on that single
system I would expect. But I think you want to have an entry that
matches the DMI_PRODUCT_NAME or DMI_FAMILY_NAME instead most likely.
> + },
> + .driver_data = &quirk_amd_7k62,
> + },
> + {}
> +};
> +MODULE_DEVICE_TABLE(dmi, amd_pstate_quirks_table);
> +
> static inline int get_mode_idx_from_str(const char *str, size_t size)
> {
> int i;
> @@ -581,13 +608,19 @@ static void amd_pstate_adjust_perf(unsigned int cpu,
> static int amd_get_min_freq(struct amd_cpudata *cpudata)
> {
> struct cppc_perf_caps cppc_perf;
> + u32 lowest_freq;
>
> int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
> if (ret)
> return ret;
>
> + if (quirks && quirks->lowest_freq)
> + lowest_freq = quirks->lowest_freq;
> + else
> + lowest_freq = cppc_perf.lowest_freq;
> +
> /* Switch to khz */
> - return cppc_perf.lowest_freq * 1000;
> + return lowest_freq * 1000;
> }
>
> static int amd_get_max_freq(struct amd_cpudata *cpudata)
> @@ -619,13 +652,14 @@ static int amd_get_max_freq(struct amd_cpudata *cpudata)
>
> static int amd_get_nominal_freq(struct amd_cpudata *cpudata)
> {
> - struct cppc_perf_caps cppc_perf;
> + u32 nominal_freq;
>
> - int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
> - if (ret)
> - return ret;
I think this hunk should be earlier in your series. Conceptually it
seems to match what patch 3 does to me.
> + if (quirks && quirks->nominal_freq)
> + nominal_freq = quirks->nominal_freq;
> + else
> + nominal_freq = READ_ONCE(cpudata->nominal_freq);
>
> - return cppc_perf.nominal_freq;
> + return nominal_freq;
> }
>
> static int amd_get_lowest_nonlinear_freq(struct amd_cpudata *cpudata)
> @@ -1623,6 +1657,11 @@ static int __init amd_pstate_init(void)
> if (cpufreq_get_current_driver())
> return -EEXIST;
>
> + quirks = NULL;
> +
> + /* check if this machine need CPPC quirks */
> + dmi_check_system(amd_pstate_quirks_table);
> +
> switch (cppc_state) {
> case AMD_PSTATE_UNDEFINED:
> /* Disable on the following configs by default:
> diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
> index 446394f84606..ea80f961607d 100644
> --- a/include/linux/amd-pstate.h
> +++ b/include/linux/amd-pstate.h
> @@ -110,4 +110,10 @@ static const char * const amd_pstate_mode_string[] = {
> [AMD_PSTATE_GUIDED] = "guided",
> NULL,
> };
> +
> +struct quirk_entry {
> + u32 nominal_freq;
> + u32 lowest_freq;
> +};
> +
> #endif /* _LINUX_AMD_PSTATE_H */
next prev parent reply other threads:[~2024-01-31 21:59 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-31 8:50 [PATCH 0/6] AMD Pstate Fixes And Enhancements Perry Yuan
2024-01-31 8:50 ` [PATCH 1/6] ACPI: CPPC: enable AMD CPPC V2 support for family 17h processors Perry Yuan
2024-01-31 21:45 ` Mario Limonciello
2024-01-31 8:50 ` [PATCH 2/6] cpufreq:amd-pstate: fix the nominal freq value set Perry Yuan
2024-01-31 21:46 ` Mario Limonciello
2024-01-31 8:50 ` [PATCH 3/6] cpufreq:amd-pstate: initialize nominal_freq of each cpudata Perry Yuan
2024-01-31 21:47 ` Mario Limonciello
2024-01-31 8:50 ` [PATCH 4/6] cpufreq:amd-pstate: get pstate transition delay and latency value from ACPI tables Perry Yuan
2024-01-31 21:49 ` Mario Limonciello
2024-01-31 8:50 ` [PATCH 5/6] cppc_acpi: print error message if CPPC is unsupported Perry Yuan
2024-01-31 21:51 ` Mario Limonciello
2024-01-31 8:50 ` [PATCH 6/6] cpufreq:amd-pstate: add quirk for the pstate CPPC capabilities missing Perry Yuan
2024-01-31 21:59 ` Mario Limonciello [this message]
2024-02-02 9:05 ` Yuan, Perry
2024-01-31 11:36 ` [PATCH 0/6] AMD Pstate Fixes And Enhancements Tor Vic
2024-02-02 9:12 ` Yuan, Perry
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=49825045-bce1-4772-b7c4-2e116e19cbaf@amd.com \
--to=mario.limonciello@amd.com \
--cc=Alexander.Deucher@amd.com \
--cc=Borislav.Petkov@amd.com \
--cc=Li.Meng@amd.com \
--cc=Ray.Huang@amd.com \
--cc=Xiaojian.Du@amd.com \
--cc=Xinmei.Huang@amd.com \
--cc=gautham.shenoy@amd.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=perry.yuan@amd.com \
--cc=rafael.j.wysocki@intel.com \
--cc=viresh.kumar@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).