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cpufreq: amd-pstate: Write CPPC enable bit per-socket

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Currently amd_pstate sets CPPC enable bit in MSR_AMD_CPPC_ENABLE only
for the CPU where the module_init happened. But MSR_AMD_CPPC_ENABLE is
per-socket. This causes CPPC enable bit to set for only one socket for
servers with more than one physical packages. To fix this write
MSR_AMD_CPPC_ENABLE per-socket.

Also, handle duplicate calls for cppc_enable, because it's called from
per-policy/per-core callbacks and can result in duplicate MSR writes.

Before the fix:
amd@amd:~$ sudo rdmsr -a 0xc00102b1 | uniq --count
	192 0
    192 1

After the fix:
amd@amd:~$ sudo rdmsr -a 0xc00102b1 | uniq --count
    384 1

Suggested-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Wyes Karny 2023-05-30 13:13:48 +00:00 committed by Rafael J. Wysocki
parent b4a11fa333
commit 217e67784e
1 changed files with 27 additions and 1 deletions
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28
drivers/cpufreq/amd-pstate.c
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@ -63,6 +63,7 @@ static struct cpufreq_driver *current_pstate_driver;
static struct cpufreq_driver amd_pstate_driver;
static struct cpufreq_driver amd_pstate_epp_driver;
static int cppc_state = AMD_PSTATE_DISABLE;
static bool cppc_enabled;
/*
* AMD Energy Preference Performance (EPP)
@ -228,7 +229,28 @@ static int amd_pstate_set_energy_pref_index(struct amd_cpudata *cpudata,
static inline int pstate_enable(bool enable)
{
return wrmsrl_safe(MSR_AMD_CPPC_ENABLE, enable);
int ret, cpu;
unsigned long logical_proc_id_mask = 0;
if (enable == cppc_enabled)
return 0;
for_each_present_cpu(cpu) {
unsigned long logical_id = topology_logical_die_id(cpu);
if (test_bit(logical_id, &logical_proc_id_mask))
continue;
set_bit(logical_id, &logical_proc_id_mask);
ret = wrmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_ENABLE,
enable);
if (ret)
return ret;
}
cppc_enabled = enable;
return 0;
}
static int cppc_enable(bool enable)
@ -236,6 +258,9 @@ static int cppc_enable(bool enable)
int cpu, ret = 0;
struct cppc_perf_ctrls perf_ctrls;
if (enable == cppc_enabled)
return 0;
for_each_present_cpu(cpu) {
ret = cppc_set_enable(cpu, enable);
if (ret)
@ -251,6 +276,7 @@ static int cppc_enable(bool enable)
}
}
cppc_enabled = enable;
return ret;
}