linux-pm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Perry Yuan <perry.yuan@amd.com>
To: <rafael.j.wysocki@intel.com>, <Mario.Limonciello@amd.com>,
	<viresh.kumar@linaro.org>, <gautham.shenoy@amd.com>,
	<Borislav.Petkov@amd.com>, <Ray.Huang@amd.com>,
	<Alexander.Deucher@amd.com>
Cc: <Xinmei.Huang@amd.com>, <oleksandr@natalenko.name>,
	<Xiaojian.Du@amd.com>, <Li.Meng@amd.com>,
	<linux-pm@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH v11 8/8] cpufreq: amd-pstate: Add quirk for the pstate CPPC capabilities missing
Date: Tue, 23 Apr 2024 15:58:24 +0800	[thread overview]
Message-ID: <381226526d045eb70a0d7fddbaff06a5e0592bb0.1713858800.git.perry.yuan@amd.com> (raw)
In-Reply-To: <cover.1713858800.git.perry.yuan@amd.com>

Add quirks 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
issues fixed with correct workaround values to make pstate driver
can be loaded even though there are CPPC capabilities errors.

The workaround will match the broken BIOS which lack of CPPC capabilities
nominal_freq and lowest_freq definition in the ACPI table.

$ cat /sys/devices/system/cpu/cpu0/acpi_cppc/lowest_freq
0
$ cat /sys/devices/system/cpu/cpu0/acpi_cppc/nominal_freq
0

Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Tested-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@amd.com>
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
---
 drivers/cpufreq/amd-pstate.c | 53 ++++++++++++++++++++++++++++++++++--
 include/linux/amd-pstate.h   |  6 ++++
 2 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 510b5aec42ea..83a29b257794 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -67,6 +67,7 @@ static struct cpufreq_driver amd_pstate_epp_driver;
 static int cppc_state = AMD_PSTATE_UNDEFINED;
 static bool cppc_enabled;
 static bool amd_pstate_prefcore = true;
+static struct quirk_entry *quirks;
 
 /*
  * AMD Energy Preference Performance (EPP)
@@ -111,6 +112,41 @@ 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_7k62_bios_bug(const struct dmi_system_id *dmi)
+{
+	/**
+	 * match the broken bios for family 17h processor support CPPC V2
+	 * broken BIOS lack of nominal_freq and lowest_freq capabilities
+	 * definition in ACPI tables
+	 */
+	if (boot_cpu_has(X86_FEATURE_ZEN2)) {
+		quirks = dmi->driver_data;
+		pr_info("Overriding nominal and lowest frequencies for %s\n", dmi->ident);
+		return 1;
+	}
+
+	return 0;
+}
+
+static const struct dmi_system_id amd_pstate_quirks_table[] __initconst = {
+	{
+		.callback = dmi_matched_7k62_bios_bug,
+		.ident = "AMD EPYC 7K62",
+		.matches = {
+			DMI_MATCH(DMI_BIOS_VERSION, "5.14"),
+			DMI_MATCH(DMI_BIOS_RELEASE, "12/12/2019"),
+		},
+		.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;
@@ -812,8 +848,16 @@ static int amd_pstate_init_freq(struct amd_cpudata *cpudata)
 	if (ret)
 		return ret;
 
-	min_freq = cppc_perf.lowest_freq * 1000;
-	nominal_freq = cppc_perf.nominal_freq;
+	if (quirks && quirks->lowest_freq)
+		min_freq = quirks->lowest_freq * 1000;
+	else
+		min_freq = cppc_perf.lowest_freq * 1000;
+
+	if (quirks && quirks->nominal_freq)
+		nominal_freq = quirks->nominal_freq ;
+	else
+		nominal_freq = cppc_perf.nominal_freq;
+
 	nominal_perf = READ_ONCE(cpudata->nominal_perf);
 
 	highest_perf = READ_ONCE(cpudata->highest_perf);
@@ -1662,6 +1706,11 @@ 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 ab7e82533718..6b832153a126 100644
--- a/include/linux/amd-pstate.h
+++ b/include/linux/amd-pstate.h
@@ -128,4 +128,10 @@ 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 */
-- 
2.34.1


  parent reply	other threads:[~2024-04-23  7:59 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-23  7:58 [PATCH v11 0/8] AMD Pstate Fixes And Enhancements Perry Yuan
2024-04-23  7:58 ` [PATCH v11 1/8] cpufreq: amd-pstate: Document *_limit_* fields in struct amd_cpudata Perry Yuan
2024-04-23 10:22   ` Huang Rui
2024-04-24  3:04     ` Yuan, Perry
2024-04-23  7:58 ` [PATCH v11 2/8] cpufreq: amd-pstate: Document the units for freq variables in amd_cpudata Perry Yuan
2024-04-23  7:58 ` [PATCH v11 3/8] cpufreq: amd-pstate: Unify computation of {max,min,nominal,lowest_nonlinear}_freq Perry Yuan
2024-04-23  7:58 ` [PATCH v11 4/8] cpufreq: amd-pstate: Remove amd_get_{min,max,nominal,lowest_nonlinear}_freq() Perry Yuan
2024-04-23  7:58 ` [PATCH v11 5/8] cpufreq: amd-pstate: Bail out if min/max/nominal_freq is 0 Perry Yuan
2024-04-23  7:58 ` [PATCH v11 6/8] cpufreq: amd-pstate: get transition delay and latency value from ACPI tables Perry Yuan
2024-04-23  7:58 ` [PATCH v11 7/8] cppc_acpi: print error message if CPPC is unsupported Perry Yuan
2024-04-23  7:58 ` Perry Yuan [this message]
2024-04-23 10:39 ` [PATCH v11 0/8] AMD Pstate Fixes And Enhancements Huang Rui

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=381226526d045eb70a0d7fddbaff06a5e0592bb0.1713858800.git.perry.yuan@amd.com \
    --to=perry.yuan@amd.com \
    --cc=Alexander.Deucher@amd.com \
    --cc=Borislav.Petkov@amd.com \
    --cc=Li.Meng@amd.com \
    --cc=Mario.Limonciello@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=oleksandr@natalenko.name \
    --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).