73  * AMD Energy Preference Performance (EPP)
74  * The EPP is used in the CCLK DPM controller to drive
76  * short periods of activity. EPP values will be utilized for
78  * display strings corresponding to EPP index in the
131 	u64 epp;  in amd_pstate_get_epp()  local
136 			epp = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ,  in amd_pstate_get_epp()
138 			if (epp)  in amd_pstate_get_epp()
139 				return epp;  in amd_pstate_get_epp()
141 		epp = (cppc_req_cached >> 24) & 0xFF;  in amd_pstate_get_epp()
143 		ret = cppc_get_epp_perf(cpudata->cpu, &epp);  in amd_pstate_get_epp()
150 	return (s16)(epp & 0xff);  in amd_pstate_get_epp()
155 	s16 epp;  in amd_pstate_get_energy_pref_index()  local
158 	epp = amd_pstate_get_epp(cpudata, 0);  in amd_pstate_get_energy_pref_index()
159 	if (epp < 0)  in amd_pstate_get_energy_pref_index()
160 		return epp;  in amd_pstate_get_energy_pref_index()
162 	switch (epp) {  in amd_pstate_get_energy_pref_index()
202 static int amd_pstate_set_epp(struct amd_cpudata *cpudata, u32 epp)  in amd_pstate_set_epp()  argument
211 		value |= (u64)epp << 24;  in amd_pstate_set_epp()
216 			cpudata->epp_cached = epp;  in amd_pstate_set_epp()
221 		perf_ctrls.energy_perf = epp;  in amd_pstate_set_epp()
227 		cpudata->epp_cached = epp;  in amd_pstate_set_epp()
236 	int epp = -EINVAL;  in amd_pstate_set_energy_pref_index()  local
240 		pr_debug("EPP pref_index is invalid\n");  in amd_pstate_set_energy_pref_index()
244 	if (epp == -EINVAL)  in amd_pstate_set_energy_pref_index()
245 		epp = epp_values[pref_index];  in amd_pstate_set_energy_pref_index()
247 	if (epp > 0 && cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {  in amd_pstate_set_energy_pref_index()
248 		pr_debug("EPP cannot be set under performance policy\n");  in amd_pstate_set_energy_pref_index()
252 	ret = amd_pstate_set_epp(cpudata, epp);  in amd_pstate_set_energy_pref_index()
296 		/* Enable autonomous mode for EPP */  in cppc_enable()
298 			/* Set desired perf as zero to allow EPP firmware control */  in cppc_enable()
1374 	s16 epp;  in amd_pstate_epp_update_limit()  local
1400 	/* CPPC EPP feature require to set zero to the desire perf bit */  in amd_pstate_epp_update_limit()
1406 	/* Get BIOS pre-defined epp value */  in amd_pstate_epp_update_limit()
1407 	epp = amd_pstate_get_epp(cpudata, value);  in amd_pstate_epp_update_limit()
1408 	if (epp < 0) {  in amd_pstate_epp_update_limit()
1411 		 * systems where EPP register read/write not supported.  in amd_pstate_epp_update_limit()
1417 		epp = 0;  in amd_pstate_epp_update_limit()
1419 	/* Set initial EPP value */  in amd_pstate_epp_update_limit()
1422 		value |= (u64)epp << 24;  in amd_pstate_epp_update_limit()
1426 	amd_pstate_set_epp(cpudata, epp);  in amd_pstate_epp_update_limit()
1538 	/* avoid suspending when EPP is not enabled */  in amd_pstate_epp_suspend()
1595 	.name		= "amd-pstate-epp",