2024-04-30 08:38:31

by Dhananjay Ugwekar

Subject: [PATCH] tools/power/cpupower: Fix Pstate frequency reporting on AMD Family 1Ah CPUs

Update cpupower's P-State frequency calculation and reporting with AMD
Family 1Ah+ processors, when using the acpi-cpufreq driver. This is due
to a change in the PStateDef MSR layout in AMD Family 1Ah+.

[ dhananjay: commit log, tested on 4th and 5th Gen AMD EPYC system ]

Signed-off-by: Ananth Narayan <[email protected]>
Signed-off-by: Dhananjay Ugwekar <[email protected]>
---
tools/power/cpupower/utils/helpers/amd.c | 26 +++++++++++++++++++++---
1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/tools/power/cpupower/utils/helpers/amd.c b/tools/power/cpupower/utils/helpers/amd.c
index c519cc89c97f..0a56e22240fc 100644
--- a/tools/power/cpupower/utils/helpers/amd.c
+++ b/tools/power/cpupower/utils/helpers/amd.c
@@ -41,6 +41,16 @@ union core_pstate {
unsigned res1:31;
unsigned en:1;
} pstatedef;
+ /* since fam 1Ah: */
+ struct {
+ unsigned fid:12;
+ unsigned res1:2;
+ unsigned vid:8;
+ unsigned iddval:8;
+ unsigned idddiv:2;
+ unsigned res2:31;
+ unsigned en:1;
+ } pstatedef2;
unsigned long long val;
};

@@ -48,6 +58,10 @@ static int get_did(union core_pstate pstate)
{
int t;

+ /* Fam 1Ah onward do not use did */
+ if (cpupower_cpu_info.family >= 0x1A)
+ return 0;
+
if (cpupower_cpu_info.caps & CPUPOWER_CAP_AMD_PSTATEDEF)
t = pstate.pstatedef.did;
else if (cpupower_cpu_info.family == 0x12)
@@ -61,12 +75,18 @@ static int get_did(union core_pstate pstate)
static int get_cof(union core_pstate pstate)
{
int t;
- int fid, did, cof;
+ int fid, did, cof = 0;

did = get_did(pstate);
if (cpupower_cpu_info.caps & CPUPOWER_CAP_AMD_PSTATEDEF) {
- fid = pstate.pstatedef.fid;
- cof = 200 * fid / did;
+ if (cpupower_cpu_info.family >= 0x1A) {
+ fid = pstate.pstatedef2.fid;
+ if (fid > 0x0f)
+ cof = (fid * 5);
+ } else {
+ fid = pstate.pstatedef.fid;
+ cof = 200 * fid / did;
+ }
} else {
t = 0x10;
fid = pstate.pstate.fid;
--
2.34.1

2024-04-30 17:06:35

by Mario Limonciello

Subject: Re: [PATCH] tools/power/cpupower: Fix Pstate frequency reporting on AMD Family 1Ah CPUs

On 4/30/2024 03:37, Dhananjay Ugwekar wrote:
> Update cpupower's P-State frequency calculation and reporting with AMD
> Family 1Ah+ processors, when using the acpi-cpufreq driver. This is due
> to a change in the PStateDef MSR layout in AMD Family 1Ah+.
>
> [ dhananjay: commit log, tested on 4th and 5th Gen AMD EPYC system ]
>
> Signed-off-by: Ananth Narayan <[email protected]>
> Signed-off-by: Dhananjay Ugwekar <[email protected]>
Reviewed-by: Mario Limonciello <[email protected]>
> ---
> tools/power/cpupower/utils/helpers/amd.c | 26 +++++++++++++++++++++---
> 1 file changed, 23 insertions(+), 3 deletions(-)
>
> diff --git a/tools/power/cpupower/utils/helpers/amd.c b/tools/power/cpupower/utils/helpers/amd.c
> index c519cc89c97f..0a56e22240fc 100644
> --- a/tools/power/cpupower/utils/helpers/amd.c
> +++ b/tools/power/cpupower/utils/helpers/amd.c
> @@ -41,6 +41,16 @@ union core_pstate {
> unsigned res1:31;
> unsigned en:1;
> } pstatedef;
> + /* since fam 1Ah: */
> + struct {
> + unsigned fid:12;
> + unsigned res1:2;
> + unsigned vid:8;
> + unsigned iddval:8;
> + unsigned idddiv:2;
> + unsigned res2:31;
> + unsigned en:1;
> + } pstatedef2;
> unsigned long long val;
> };
>
> @@ -48,6 +58,10 @@ static int get_did(union core_pstate pstate)
> {
> int t;
>
> + /* Fam 1Ah onward do not use did */
> + if (cpupower_cpu_info.family >= 0x1A)
> + return 0;
> +
> if (cpupower_cpu_info.caps & CPUPOWER_CAP_AMD_PSTATEDEF)
> t = pstate.pstatedef.did;
> else if (cpupower_cpu_info.family == 0x12)
> @@ -61,12 +75,18 @@ static int get_did(union core_pstate pstate)
> static int get_cof(union core_pstate pstate)
> {
> int t;
> - int fid, did, cof;
> + int fid, did, cof = 0;
>
> did = get_did(pstate);
> if (cpupower_cpu_info.caps & CPUPOWER_CAP_AMD_PSTATEDEF) {
> - fid = pstate.pstatedef.fid;
> - cof = 200 * fid / did;
> + if (cpupower_cpu_info.family >= 0x1A) {
> + fid = pstate.pstatedef2.fid;
> + if (fid > 0x0f)
> + cof = (fid * 5);
> + } else {
> + fid = pstate.pstatedef.fid;
> + cof = 200 * fid / did;
> + }
> } else {
> t = 0x10;
> fid = pstate.pstate.fid;

2024-05-02 15:42:10

by Shuah Khan

Subject: Re: [PATCH] tools/power/cpupower: Fix Pstate frequency reporting on AMD Family 1Ah CPUs

On 4/30/24 11:06, Mario Limonciello wrote:
> On 4/30/2024 03:37, Dhananjay Ugwekar wrote:
>> Update cpupower's P-State frequency calculation and reporting with AMD
>> Family 1Ah+ processors, when using the acpi-cpufreq driver. This is due
>> to a change in the PStateDef MSR layout in AMD Family 1Ah+.
>>
>> [ dhananjay: commit log, tested on 4th and 5th Gen AMD EPYC system ]
>>
>> Signed-off-by: Ananth Narayan <[email protected]>
>> Signed-off-by: Dhananjay Ugwekar <[email protected]>
> Reviewed-by: Mario Limonciello <[email protected]>

Thank you. Applied to

git.kernel.org/pub/scm/linux/kernel/git/shuah/linux.git/log/ cpupower
branch for Linux 6.10-rc1.

I will include it in my pull request to Rafael.

thanks
-- Shuah