cpufreq/amd-pstate: Prefix setup messages with FW_BUG

[PATCH] cpufreq/amd-pstate: Prefix setup messages with FW_BUG

Posted by Mario Limonciello 9 months ago

From: Mario Limonciello <mario.limonciello@amd.com>

To make it clearer that amd-pstate failing to setup is a problem
with the firmware, prefix several messages with FW_BUG.

Suggested-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 drivers/cpufreq/amd-pstate.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 024d33d5e3670..0a9d6fe426d1c 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -931,13 +931,13 @@ static int amd_pstate_init_freq(struct amd_cpudata *cpudata)
 	 * Check _CPC in ACPI table objects if any values are incorrect
 	 */
 	if (min_freq <= 0 || max_freq <= 0 || nominal_freq <= 0 || min_freq > max_freq) {
-		pr_err("min_freq(%d) or max_freq(%d) or nominal_freq(%d) value is incorrect\n",
+		pr_err(FW_BUG "min_freq(%d) or max_freq(%d) or nominal_freq(%d) value is incorrect\n",
 			min_freq, max_freq, nominal_freq);
 		return -EINVAL;
 	}
 
 	if (lowest_nonlinear_freq <= min_freq || lowest_nonlinear_freq > nominal_freq) {
-		pr_err("lowest_nonlinear_freq(%d) value is out of range [min_freq(%d), nominal_freq(%d)]\n",
+		pr_err(FW_BUG "lowest_nonlinear_freq(%d) value is out of range [min_freq(%d), nominal_freq(%d)]\n",
 			lowest_nonlinear_freq, min_freq, nominal_freq);
 		return -EINVAL;
 	}
@@ -1505,7 +1505,7 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
 	return 0;
 
 free_cpudata1:
-	pr_warn("Failed to initialize CPU %d: %d\n", policy->cpu, ret);
+	pr_warn(FW_BUG "Failed to initialize CPU %d: %d\n", policy->cpu, ret);
 	kfree(cpudata);
 	return ret;
 }
-- 
2.43.0

Re: [PATCH] cpufreq/amd-pstate: Prefix setup messages with FW_BUG

Posted by Dhananjay Ugwekar 8 months, 3 weeks ago

On 3/21/2025 3:11 AM, Mario Limonciello wrote:
> From: Mario Limonciello <mario.limonciello@amd.com>
> 
> To make it clearer that amd-pstate failing to setup is a problem
> with the firmware, prefix several messages with FW_BUG.
> 
> Suggested-by: Paul Menzel <pmenzel@molgen.mpg.de>
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> ---
>  drivers/cpufreq/amd-pstate.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 024d33d5e3670..0a9d6fe426d1c 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -931,13 +931,13 @@ static int amd_pstate_init_freq(struct amd_cpudata *cpudata)
>  	 * Check _CPC in ACPI table objects if any values are incorrect
>  	 */
>  	if (min_freq <= 0 || max_freq <= 0 || nominal_freq <= 0 || min_freq > max_freq) {
> -		pr_err("min_freq(%d) or max_freq(%d) or nominal_freq(%d) value is incorrect\n",
> +		pr_err(FW_BUG "min_freq(%d) or max_freq(%d) or nominal_freq(%d) value is incorrect\n",
>  			min_freq, max_freq, nominal_freq);
>  		return -EINVAL;
>  	}
>  
>  	if (lowest_nonlinear_freq <= min_freq || lowest_nonlinear_freq > nominal_freq) {
> -		pr_err("lowest_nonlinear_freq(%d) value is out of range [min_freq(%d), nominal_freq(%d)]\n",
> +		pr_err(FW_BUG "lowest_nonlinear_freq(%d) value is out of range [min_freq(%d), nominal_freq(%d)]\n",
>  			lowest_nonlinear_freq, min_freq, nominal_freq);
>  		return -EINVAL;
>  	}
> @@ -1505,7 +1505,7 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
>  	return 0;
>  
>  free_cpudata1:
> -	pr_warn("Failed to initialize CPU %d: %d\n", policy->cpu, ret);
> +	pr_warn(FW_BUG "Failed to initialize CPU %d: %d\n", policy->cpu, ret);

Just thinking are we sure that we land here only through a firmware bug?

If not, we should probably use FW_WARN ?, 
or 
Should we add to the error message the specific firmware issue that might cause 
each of the functions to fail (e.g. amd_pstate_init_perf(), amd_pstate_init_freq(), 
etc). 

Comments for the macros, for reference,

 * FW_BUG
 * Add this to a message where you are sure the firmware is buggy or behaves
 * really stupid or out of spec. Be aware that the responsible BIOS developer
 * should be able to fix this issue or at least get a concrete idea of the
 * problem by reading your message without the need of looking at the kernel
 * code.
 *
 * Use it for definite and high priority BIOS bugs.
 *
 * FW_WARN
 * Use it for not that clear (e.g. could the kernel messed up things already?)
 * and medium priority BIOS bugs.

>  	kfree(cpudata);
>  	return ret;
>  }

Re: [PATCH] cpufreq/amd-pstate: Prefix setup messages with FW_BUG

Posted by Mario Limonciello 8 months, 2 weeks ago

On 3/28/2025 2:20 AM, Dhananjay Ugwekar wrote:
> On 3/21/2025 3:11 AM, Mario Limonciello wrote:
>> From: Mario Limonciello <mario.limonciello@amd.com>
>>
>> To make it clearer that amd-pstate failing to setup is a problem
>> with the firmware, prefix several messages with FW_BUG.
>>
>> Suggested-by: Paul Menzel <pmenzel@molgen.mpg.de>
>> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
>> ---
>>   drivers/cpufreq/amd-pstate.c | 6 +++---
>>   1 file changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
>> index 024d33d5e3670..0a9d6fe426d1c 100644
>> --- a/drivers/cpufreq/amd-pstate.c
>> +++ b/drivers/cpufreq/amd-pstate.c
>> @@ -931,13 +931,13 @@ static int amd_pstate_init_freq(struct amd_cpudata *cpudata)
>>   	 * Check _CPC in ACPI table objects if any values are incorrect
>>   	 */
>>   	if (min_freq <= 0 || max_freq <= 0 || nominal_freq <= 0 || min_freq > max_freq) {
>> -		pr_err("min_freq(%d) or max_freq(%d) or nominal_freq(%d) value is incorrect\n",
>> +		pr_err(FW_BUG "min_freq(%d) or max_freq(%d) or nominal_freq(%d) value is incorrect\n",
>>   			min_freq, max_freq, nominal_freq);
>>   		return -EINVAL;
>>   	}
>>   
>>   	if (lowest_nonlinear_freq <= min_freq || lowest_nonlinear_freq > nominal_freq) {
>> -		pr_err("lowest_nonlinear_freq(%d) value is out of range [min_freq(%d), nominal_freq(%d)]\n",
>> +		pr_err(FW_BUG "lowest_nonlinear_freq(%d) value is out of range [min_freq(%d), nominal_freq(%d)]\n",
>>   			lowest_nonlinear_freq, min_freq, nominal_freq);
>>   		return -EINVAL;
>>   	}
>> @@ -1505,7 +1505,7 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
>>   	return 0;
>>   
>>   free_cpudata1:
>> -	pr_warn("Failed to initialize CPU %d: %d\n", policy->cpu, ret);
>> +	pr_warn(FW_BUG "Failed to initialize CPU %d: %d\n", policy->cpu, ret);
> 
> Just thinking are we sure that we land here only through a firmware bug?
> 
> If not, we should probably use FW_WARN ?,
> or
> Should we add to the error message the specific firmware issue that might cause
> each of the functions to fail (e.g. amd_pstate_init_perf(), amd_pstate_init_freq(),
> etc).

I looked at the call paths and I'm not convinced that they will all be 
firmware bugs.  In any case I want to know whenever there is a failure 
here so we can evaluate if it's a firmware bug or a software bug.

If it's a software bug we'll obviously work on it, and if it's a 
firmware bug do our best to notify the firmware developer.

So I will abandon this patch, thanks for the great feedback.

> 
> Comments for the macros, for reference,
> 
>   * FW_BUG
>   * Add this to a message where you are sure the firmware is buggy or behaves
>   * really stupid or out of spec. Be aware that the responsible BIOS developer
>   * should be able to fix this issue or at least get a concrete idea of the
>   * problem by reading your message without the need of looking at the kernel
>   * code.
>   *
>   * Use it for definite and high priority BIOS bugs.
>   *
>   * FW_WARN
>   * Use it for not that clear (e.g. could the kernel messed up things already?)
>   * and medium priority BIOS bugs.
> 
>>   	kfree(cpudata);
>>   	return ret;
>>   }
>