[PATCH V3 5/7] cpufreq: amd-pstate: Update AMD Pstate Preferred Core ranking dynamically

[Meng Li]

Preferred core rankings can be changed dynamically by the
platform based on the workload and platform conditions and
accounting for thermals and aging.
When this occurs, cpu priority need to be set.

Signed-off-by: Meng Li <li.meng@xxxxxxx>
---
 drivers/cpufreq/amd-pstate.c | 32 ++++++++++++++++++++++++++++++++
 include/linux/amd-pstate.h   |  1 +
 2 files changed, 33 insertions(+)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index d02305675f66..8a8e4ecb1b5c 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -315,6 +315,7 @@ static int pstate_init_perf(struct amd_cpudata *cpudata)
 	WRITE_ONCE(cpudata->nominal_perf, AMD_CPPC_NOMINAL_PERF(cap1));
 	WRITE_ONCE(cpudata->lowest_nonlinear_perf, AMD_CPPC_LOWNONLIN_PERF(cap1));
 	WRITE_ONCE(cpudata->lowest_perf, AMD_CPPC_LOWEST_PERF(cap1));
+	WRITE_ONCE(cpudata->prefcore_highest_perf, AMD_CPPC_HIGHEST_PERF(cap1));
 
 	return 0;
 }
@@ -336,6 +337,7 @@ static int cppc_init_perf(struct amd_cpudata *cpudata)
 	WRITE_ONCE(cpudata->lowest_nonlinear_perf,
 		   cppc_perf.lowest_nonlinear_perf);
 	WRITE_ONCE(cpudata->lowest_perf, cppc_perf.lowest_perf);
+	WRITE_ONCE(cpudata->prefcore_highest_perf, cppc_perf.highest_perf);
 
 	if (cppc_state == AMD_PSTATE_ACTIVE)
 		return 0;
@@ -744,6 +746,34 @@ static void amd_pstate_init_prefcore(void)
 	schedule_work(&sched_prefcore_work);
 }
 
+static void amd_pstate_update_highest_perf(unsigned int cpu)
+{
+	struct cpufreq_policy *policy;
+	struct amd_cpudata *cpudata;
+	u32 prev_high = 0, cur_high = 0;
+	u64 highest_perf;
+	int ret;
+
+	if (!prefcore)
+		return;
+
+	ret = amd_pstate_get_highest_perf(cpu, &highest_perf);
+	if (ret)
+		return;
+
+	policy = cpufreq_cpu_get(cpu);
+	cpudata = policy->driver_data;
+	cur_high = highest_perf;
+	prev_high = READ_ONCE(cpudata->prefcore_highest_perf);
+
+	if (prev_high != cur_high) {
+		WRITE_ONCE(cpudata->prefcore_highest_perf, cur_high);
+		sched_set_itmt_core_prio(cur_high, cpu);
+	}
+
+	cpufreq_cpu_put(policy);
+}
+
 static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
 {
 	int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret;
@@ -1468,6 +1498,7 @@ static struct cpufreq_driver amd_pstate_driver = {
 	.suspend	= amd_pstate_cpu_suspend,
 	.resume		= amd_pstate_cpu_resume,
 	.set_boost	= amd_pstate_set_boost,
+	.update_highest_perf	= amd_pstate_update_highest_perf,
 	.name		= "amd-pstate",
 	.attr		= amd_pstate_attr,
 };
@@ -1482,6 +1513,7 @@ static struct cpufreq_driver amd_pstate_epp_driver = {
 	.online		= amd_pstate_epp_cpu_online,
 	.suspend	= amd_pstate_epp_suspend,
 	.resume		= amd_pstate_epp_resume,
+	.update_highest_perf	= amd_pstate_update_highest_perf,
 	.name		= "amd-pstate-epp",
 	.attr		= amd_pstate_epp_attr,
 };
diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
index 446394f84606..fa86bc953d3e 100644
--- a/include/linux/amd-pstate.h
+++ b/include/linux/amd-pstate.h
@@ -70,6 +70,7 @@ struct amd_cpudata {
 	u32	nominal_perf;
 	u32	lowest_nonlinear_perf;
 	u32	lowest_perf;
+	u32     prefcore_highest_perf;
 
 	u32	max_freq;
 	u32	min_freq;
-- 
2.34.1