On Fri, Sep 10, 2021 at 06:16:50AM +0800, Shuah Khan wrote:

On 9/8/21 8:59 AM, Huang Rui wrote:

quoted

If kernel enables AMD P-state, cpupower won't need to respond ACPI
hardware P-states function anymore.

This commit log doesn't seem to match the code change. I see it
calling cpupower_amd_pstate_enabled() and setting flags.

Hmm, yes, I should reword this as well. If the kernel uses the amd-pstate
module, we only need CPUPOWER_CAP_AMD_PSTATE flag, and disable the legacy
acpi-cpufreq relative flags.

quoted

Signed-off-by: Huang Rui <ray.huang@amd.com>
---
  tools/power/cpupower/utils/helpers/cpuid.c | 13 +++++++++++++
  1 file changed, 13 insertions(+)

diff --git a/tools/power/cpupower/utils/helpers/cpuid.c b/tools/power/cpupower/utils/helpers/cpuid.c
index 72eb43593180..78218c54acca 100644
--- a/tools/power/cpupower/utils/helpers/cpuid.c
+++ b/tools/power/cpupower/utils/helpers/cpuid.c

@@ -149,6 +149,19 @@ int get_cpu_info(struct cpupower_cpu_info *cpu_info)
  		if (ext_cpuid_level >= 0x80000008 &&
  		    cpuid_ebx(0x80000008) & (1 << 4))
  			cpu_info->caps |= CPUPOWER_CAP_AMD_RDPRU;
+
+		if (cpupower_amd_pstate_enabled(0)) {

What is the reason for calling this function with cpu id = 0?

No specific reason, actually, any cpu id should be ok here.

Thanks,
Ray

quoted

+			cpu_info->caps |= CPUPOWER_CAP_AMD_PSTATE;
+
+			/*
+			 * If AMD P-state is enabled, the firmware will treat
+			 * AMD P-state function as high priority.
+			 */
+			cpu_info->caps &= ~CPUPOWER_CAP_AMD_CPB;
+			cpu_info->caps &= ~CPUPOWER_CAP_AMD_CPB_MSR;
+			cpu_info->caps &= ~CPUPOWER_CAP_AMD_HW_PSTATE;
+			cpu_info->caps &= ~CPUPOWER_CAP_AMD_PSTATEDEF;
+		}
  	}
  
  	if (cpu_info->vendor == X86_VENDOR_INTEL) {

thanks,
-- Shuah