diff mbox series

[v4,10/11] cpufreq: amd-pstate: auto-load pstate driver by default

Message ID 0a4699e224e1931c09d6ede2620d585382b7d168.1718606975.git.perry.yuan@amd.com (mailing list archive)
State Superseded, archived
Headers show
Series AMD Pstate Driver Fixes and Improvements | expand

Commit Message

Yuan, Perry June 17, 2024, 6:59 a.m. UTC
If the `amd-pstate` driver is not loaded automatically by default,
it is because the kernel command line parameter has not been added.
To resolve this issue, it is necessary to call the `amd_pstate_set_driver()`
function to enable the desired mode (passive/active/guided) before registering
the driver instance.

This ensures that the driver is loaded correctly without relying on the kernel
command line parameter.

When there is no parameter added to command line, Kernel config will
provide the default mode to load.

Meanwhle, user can add driver mode in command line which will override
the kernel config default option.

Reported-by: Andrei Amuraritei <andamu@posteo.net>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218705
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
---
 drivers/cpufreq/amd-pstate.c | 24 +++++++++++++++++-------
 1 file changed, 17 insertions(+), 7 deletions(-)

Comments

Mario Limonciello June 18, 2024, 7:25 p.m. UTC | #1
On 6/17/2024 01:59, Perry Yuan wrote:
> If the `amd-pstate` driver is not loaded automatically by default,
> it is because the kernel command line parameter has not been added.
> To resolve this issue, it is necessary to call the `amd_pstate_set_driver()`
> function to enable the desired mode (passive/active/guided) before registering
> the driver instance.
> 
> This ensures that the driver is loaded correctly without relying on the kernel
> command line parameter.
> 
> When there is no parameter added to command line, Kernel config will
> provide the default mode to load.
> 
> Meanwhle, user can add driver mode in command line which will override

Meanwhile

> the kernel config default option.

I think you'll probably want to swap the order of patch 10 and patch 11.

> 
> Reported-by: Andrei Amuraritei <andamu@posteo.net>
> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218705
> Signed-off-by: Perry Yuan <perry.yuan@amd.com>

Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>

> ---
>   drivers/cpufreq/amd-pstate.c | 24 +++++++++++++++++-------
>   1 file changed, 17 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index cf68343219d1..b48fd60cbc6d 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -1857,8 +1857,13 @@ static int __init amd_pstate_init(void)
>   	/* check if this machine need CPPC quirks */
>   	dmi_check_system(amd_pstate_quirks_table);
>   
> -	switch (cppc_state) {
> -	case AMD_PSTATE_UNDEFINED:
> +	/*
> +	* determine the driver mode from the command line or kernel config.
> +	* If no command line input is provided, cppc_state will be AMD_PSTATE_UNDEFINED.
> +	* command line options will override the kernel config settings.
> +	*/
> +
> +	if (cppc_state == AMD_PSTATE_UNDEFINED) {
>   		/* Disable on the following configs by default:
>   		 * 1. Undefined platforms
>   		 * 2. Server platforms
> @@ -1870,15 +1875,20 @@ static int __init amd_pstate_init(void)
>   			pr_info("driver load is disabled, boot with specific mode to enable this\n");
>   			return -ENODEV;
>   		}
> -		ret = amd_pstate_set_driver(CONFIG_X86_AMD_PSTATE_DEFAULT_MODE);
> -		if (ret)
> -			return ret;
> -		break;
> +		/* get driver mode from kernel config option [1:4] */
> +		cppc_state = CONFIG_X86_AMD_PSTATE_DEFAULT_MODE;
> +	}
> +
> +	switch (cppc_state) {
>   	case AMD_PSTATE_DISABLE:
> +		pr_info("driver load is disabled, boot with specific mode to enable this\n");
>   		return -ENODEV;
>   	case AMD_PSTATE_PASSIVE:
>   	case AMD_PSTATE_ACTIVE:
>   	case AMD_PSTATE_GUIDED:
> +		ret = amd_pstate_set_driver(cppc_state);
> +		if (ret)
> +			return ret;
>   		break;
>   	default:
>   		return -EINVAL;
> @@ -1899,7 +1909,7 @@ static int __init amd_pstate_init(void)
>   	/* enable amd pstate feature */
>   	ret = amd_pstate_enable(true);
>   	if (ret) {
> -		pr_err("failed to enable with return %d\n", ret);
> +		pr_err("failed to enable driver mode(%d)\n", cppc_state);
>   		return ret;
>   	}
>
Yuan, Perry June 19, 2024, 3:08 a.m. UTC | #2
[AMD Official Use Only - AMD Internal Distribution Only]

Hi Mario

> -----Original Message-----
> From: Limonciello, Mario <Mario.Limonciello@amd.com>
> Sent: Wednesday, June 19, 2024 3:25 AM
> To: Yuan, Perry <Perry.Yuan@amd.com>; rafael.j.wysocki@intel.com;
> viresh.kumar@linaro.org; Huang, Ray <Ray.Huang@amd.com>; Shenoy,
> Gautham Ranjal <gautham.shenoy@amd.com>; Petkov, Borislav
> <Borislav.Petkov@amd.com>
> Cc: Deucher, Alexander <Alexander.Deucher@amd.com>; Huang, Shimmer
> <Shimmer.Huang@amd.com>; Du, Xiaojian <Xiaojian.Du@amd.com>; Meng,
> Li (Jassmine) <Li.Meng@amd.com>; linux-pm@vger.kernel.org; linux-
> kernel@vger.kernel.org
> Subject: Re: [PATCH v4 10/11] cpufreq: amd-pstate: auto-load pstate driver by
> default
>
> On 6/17/2024 01:59, Perry Yuan wrote:
> > If the `amd-pstate` driver is not loaded automatically by default, it
> > is because the kernel command line parameter has not been added.
> > To resolve this issue, it is necessary to call the
> > `amd_pstate_set_driver()` function to enable the desired mode
> > (passive/active/guided) before registering the driver instance.
> >
> > This ensures that the driver is loaded correctly without relying on
> > the kernel command line parameter.
> >
> > When there is no parameter added to command line, Kernel config will
> > provide the default mode to load.
> >
> > Meanwhle, user can add driver mode in command line which will override
>
> Meanwhile
>
> > the kernel config default option.
>
> I think you'll probably want to swap the order of patch 10 and patch 11.

Sure, that will be more reasonable to set epp loaded by default for MSR and shared memory systems.
Let me swap them in v5.
Thanks for the review.


>
> >
> > Reported-by: Andrei Amuraritei <andamu@posteo.net>
> > Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218705
> > Signed-off-by: Perry Yuan <perry.yuan@amd.com>
>
> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
>
> > ---
> >   drivers/cpufreq/amd-pstate.c | 24 +++++++++++++++++-------
> >   1 file changed, 17 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/cpufreq/amd-pstate.c
> > b/drivers/cpufreq/amd-pstate.c index cf68343219d1..b48fd60cbc6d
> 100644
> > --- a/drivers/cpufreq/amd-pstate.c
> > +++ b/drivers/cpufreq/amd-pstate.c
> > @@ -1857,8 +1857,13 @@ static int __init amd_pstate_init(void)
> >     /* check if this machine need CPPC quirks */
> >     dmi_check_system(amd_pstate_quirks_table);
> >
> > -   switch (cppc_state) {
> > -   case AMD_PSTATE_UNDEFINED:
> > +   /*
> > +   * determine the driver mode from the command line or kernel
> config.
> > +   * If no command line input is provided, cppc_state will be
> AMD_PSTATE_UNDEFINED.
> > +   * command line options will override the kernel config settings.
> > +   */
> > +
> > +   if (cppc_state == AMD_PSTATE_UNDEFINED) {
> >             /* Disable on the following configs by default:
> >              * 1. Undefined platforms
> >              * 2. Server platforms
> > @@ -1870,15 +1875,20 @@ static int __init amd_pstate_init(void)
> >                     pr_info("driver load is disabled, boot with specific
> mode to enable this\n");
> >                     return -ENODEV;
> >             }
> > -           ret =
> amd_pstate_set_driver(CONFIG_X86_AMD_PSTATE_DEFAULT_MODE);
> > -           if (ret)
> > -                   return ret;
> > -           break;
> > +           /* get driver mode from kernel config option [1:4] */
> > +           cppc_state = CONFIG_X86_AMD_PSTATE_DEFAULT_MODE;
> > +   }
> > +
> > +   switch (cppc_state) {
> >     case AMD_PSTATE_DISABLE:
> > +           pr_info("driver load is disabled, boot with specific mode to
> enable
> > +this\n");
> >             return -ENODEV;
> >     case AMD_PSTATE_PASSIVE:
> >     case AMD_PSTATE_ACTIVE:
> >     case AMD_PSTATE_GUIDED:
> > +           ret = amd_pstate_set_driver(cppc_state);
> > +           if (ret)
> > +                   return ret;
> >             break;
> >     default:
> >             return -EINVAL;
> > @@ -1899,7 +1909,7 @@ static int __init amd_pstate_init(void)
> >     /* enable amd pstate feature */
> >     ret = amd_pstate_enable(true);
> >     if (ret) {
> > -           pr_err("failed to enable with return %d\n", ret);
> > +           pr_err("failed to enable driver mode(%d)\n", cppc_state);
> >             return ret;
> >     }
> >
diff mbox series

Patch

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index cf68343219d1..b48fd60cbc6d 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -1857,8 +1857,13 @@  static int __init amd_pstate_init(void)
 	/* check if this machine need CPPC quirks */
 	dmi_check_system(amd_pstate_quirks_table);
 
-	switch (cppc_state) {
-	case AMD_PSTATE_UNDEFINED:
+	/*
+	* determine the driver mode from the command line or kernel config.
+	* If no command line input is provided, cppc_state will be AMD_PSTATE_UNDEFINED.
+	* command line options will override the kernel config settings.
+	*/
+
+	if (cppc_state == AMD_PSTATE_UNDEFINED) {
 		/* Disable on the following configs by default:
 		 * 1. Undefined platforms
 		 * 2. Server platforms
@@ -1870,15 +1875,20 @@  static int __init amd_pstate_init(void)
 			pr_info("driver load is disabled, boot with specific mode to enable this\n");
 			return -ENODEV;
 		}
-		ret = amd_pstate_set_driver(CONFIG_X86_AMD_PSTATE_DEFAULT_MODE);
-		if (ret)
-			return ret;
-		break;
+		/* get driver mode from kernel config option [1:4] */
+		cppc_state = CONFIG_X86_AMD_PSTATE_DEFAULT_MODE;
+	}
+
+	switch (cppc_state) {
 	case AMD_PSTATE_DISABLE:
+		pr_info("driver load is disabled, boot with specific mode to enable this\n");
 		return -ENODEV;
 	case AMD_PSTATE_PASSIVE:
 	case AMD_PSTATE_ACTIVE:
 	case AMD_PSTATE_GUIDED:
+		ret = amd_pstate_set_driver(cppc_state);
+		if (ret)
+			return ret;
 		break;
 	default:
 		return -EINVAL;
@@ -1899,7 +1909,7 @@  static int __init amd_pstate_init(void)
 	/* enable amd pstate feature */
 	ret = amd_pstate_enable(true);
 	if (ret) {
-		pr_err("failed to enable with return %d\n", ret);
+		pr_err("failed to enable driver mode(%d)\n", cppc_state);
 		return ret;
 	}