1 /*
2  * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <debug.h>
9 #include <platform.h>
10 #include <platform_def.h>
11 #include "psci_private.h"
12 
13 #ifndef PLAT_MAX_PWR_LVL_STATES
14 #define PLAT_MAX_PWR_LVL_STATES 2
15 #endif
16 
17 /* Following structure is used for PSCI STAT */
18 typedef struct psci_stat {
19 	u_register_t residency;
20 	u_register_t count;
21 } psci_stat_t;
22 
23 /*
24  * Following is used to keep track of the last cpu
25  * that goes to power down in non cpu power domains.
26  */
27 static int last_cpu_in_non_cpu_pd[PSCI_NUM_NON_CPU_PWR_DOMAINS] = {-1};
28 
29 /*
30  * Following are used to store PSCI STAT values for
31  * CPU and non CPU power domains.
32  */
33 static psci_stat_t psci_cpu_stat[PLATFORM_CORE_COUNT]
34 				[PLAT_MAX_PWR_LVL_STATES];
35 static psci_stat_t psci_non_cpu_stat[PSCI_NUM_NON_CPU_PWR_DOMAINS]
36 				[PLAT_MAX_PWR_LVL_STATES];
37 
38 /*
39  * This functions returns the index into the `psci_stat_t` array given the
40  * local power state and power domain level. If the platform implements the
41  * `get_pwr_lvl_state_idx` pm hook, then that will be used to return the index.
42  */
get_stat_idx(plat_local_state_t local_state,int pwr_lvl)43 static int get_stat_idx(plat_local_state_t local_state, int pwr_lvl)
44 {
45 	int idx;
46 
47 	if (psci_plat_pm_ops->get_pwr_lvl_state_idx == NULL) {
48 		assert(PLAT_MAX_PWR_LVL_STATES == 2);
49 		if (is_local_state_retn(local_state))
50 			return 0;
51 
52 		assert(is_local_state_off(local_state));
53 		return 1;
54 	}
55 
56 	idx = psci_plat_pm_ops->get_pwr_lvl_state_idx(local_state, pwr_lvl);
57 	assert((idx >= 0) && (idx < PLAT_MAX_PWR_LVL_STATES));
58 	return idx;
59 }
60 
61 /*******************************************************************************
62  * This function is passed the target local power states for each power
63  * domain (state_info) between the current CPU domain and its ancestors until
64  * the target power level (end_pwrlvl).
65  *
66  * Then, for each level (apart from the CPU level) until the 'end_pwrlvl', it
67  * updates the `last_cpu_in_non_cpu_pd[]` with last power down cpu id.
68  *
69  * This function will only be invoked with data cache enabled and while
70  * powering down a core.
71  ******************************************************************************/
psci_stats_update_pwr_down(unsigned int end_pwrlvl,const psci_power_state_t * state_info)72 void psci_stats_update_pwr_down(unsigned int end_pwrlvl,
73 			const psci_power_state_t *state_info)
74 {
75 	unsigned int lvl, parent_idx, cpu_idx = plat_my_core_pos();
76 
77 	assert(end_pwrlvl <= PLAT_MAX_PWR_LVL);
78 	assert(state_info);
79 
80 	parent_idx = psci_cpu_pd_nodes[cpu_idx].parent_node;
81 
82 	for (lvl = PSCI_CPU_PWR_LVL + 1; lvl <= end_pwrlvl; lvl++) {
83 
84 		/* Break early if the target power state is RUN */
85 		if (is_local_state_run(state_info->pwr_domain_state[lvl]))
86 			break;
87 
88 		/*
89 		 * The power domain is entering a low power state, so this is
90 		 * the last CPU for this power domain
91 		 */
92 		last_cpu_in_non_cpu_pd[parent_idx] = cpu_idx;
93 
94 		parent_idx = psci_non_cpu_pd_nodes[parent_idx].parent_node;
95 	}
96 
97 }
98 
99 /*******************************************************************************
100  * This function updates the PSCI STATS(residency time and count) for CPU
101  * and NON-CPU power domains.
102  * It is called with caches enabled and locks acquired(for NON-CPU domain)
103  ******************************************************************************/
psci_stats_update_pwr_up(unsigned int end_pwrlvl,const psci_power_state_t * state_info)104 void psci_stats_update_pwr_up(unsigned int end_pwrlvl,
105 			const psci_power_state_t *state_info)
106 {
107 	unsigned int lvl, parent_idx, cpu_idx = plat_my_core_pos();
108 	int stat_idx;
109 	plat_local_state_t local_state;
110 	u_register_t residency;
111 
112 	assert(end_pwrlvl <= PLAT_MAX_PWR_LVL);
113 	assert(state_info);
114 
115 	/* Get the index into the stats array */
116 	local_state = state_info->pwr_domain_state[PSCI_CPU_PWR_LVL];
117 	stat_idx = get_stat_idx(local_state, PSCI_CPU_PWR_LVL);
118 
119 	/* Call into platform interface to calculate residency. */
120 	residency = plat_psci_stat_get_residency(PSCI_CPU_PWR_LVL,
121 	    state_info, cpu_idx);
122 
123 	/* Update CPU stats. */
124 	psci_cpu_stat[cpu_idx][stat_idx].residency += residency;
125 	psci_cpu_stat[cpu_idx][stat_idx].count++;
126 
127 	/*
128 	 * Check what power domains above CPU were off
129 	 * prior to this CPU powering on.
130 	 */
131 	parent_idx = psci_cpu_pd_nodes[cpu_idx].parent_node;
132 	for (lvl = PSCI_CPU_PWR_LVL + 1; lvl <= end_pwrlvl; lvl++) {
133 		local_state = state_info->pwr_domain_state[lvl];
134 		if (is_local_state_run(local_state)) {
135 			/* Break early */
136 			break;
137 		}
138 
139 		assert(last_cpu_in_non_cpu_pd[parent_idx] != -1);
140 
141 		/* Call into platform interface to calculate residency. */
142 		residency = plat_psci_stat_get_residency(lvl, state_info,
143 		    last_cpu_in_non_cpu_pd[parent_idx]);
144 
145 		/* Initialize back to reset value */
146 		last_cpu_in_non_cpu_pd[parent_idx] = -1;
147 
148 		/* Get the index into the stats array */
149 		stat_idx = get_stat_idx(local_state, lvl);
150 
151 		/* Update non cpu stats */
152 		psci_non_cpu_stat[parent_idx][stat_idx].residency += residency;
153 		psci_non_cpu_stat[parent_idx][stat_idx].count++;
154 
155 		parent_idx = psci_non_cpu_pd_nodes[parent_idx].parent_node;
156 	}
157 
158 }
159 
160 /*******************************************************************************
161  * This function returns the appropriate count and residency time of the
162  * local state for the highest power level expressed in the `power_state`
163  * for the node represented by `target_cpu`.
164  ******************************************************************************/
psci_get_stat(u_register_t target_cpu,unsigned int power_state,psci_stat_t * psci_stat)165 static int psci_get_stat(u_register_t target_cpu, unsigned int power_state,
166 			 psci_stat_t *psci_stat)
167 {
168 	int rc;
169 	unsigned int pwrlvl, lvl, parent_idx, stat_idx, target_idx;
170 	psci_power_state_t state_info = { {PSCI_LOCAL_STATE_RUN} };
171 	plat_local_state_t local_state;
172 
173 	/* Validate the target_cpu parameter and determine the cpu index */
174 	target_idx = plat_core_pos_by_mpidr(target_cpu);
175 	if (target_idx == -1)
176 		return PSCI_E_INVALID_PARAMS;
177 
178 	/* Validate the power_state parameter */
179 	if (!psci_plat_pm_ops->translate_power_state_by_mpidr)
180 		rc = psci_validate_power_state(power_state, &state_info);
181 	else
182 		rc = psci_plat_pm_ops->translate_power_state_by_mpidr(
183 				target_cpu, power_state, &state_info);
184 
185 	if (rc != PSCI_E_SUCCESS)
186 		return PSCI_E_INVALID_PARAMS;
187 
188 	/* Find the highest power level */
189 	pwrlvl = psci_find_target_suspend_lvl(&state_info);
190 	if (pwrlvl == PSCI_INVALID_PWR_LVL) {
191 		ERROR("Invalid target power level for PSCI statistics operation\n");
192 		panic();
193 	}
194 
195 	/* Get the index into the stats array */
196 	local_state = state_info.pwr_domain_state[pwrlvl];
197 	stat_idx = get_stat_idx(local_state, pwrlvl);
198 
199 	if (pwrlvl > PSCI_CPU_PWR_LVL) {
200 		/* Get the power domain index */
201 		parent_idx = psci_cpu_pd_nodes[target_idx].parent_node;
202 		for (lvl = PSCI_CPU_PWR_LVL + 1; lvl < pwrlvl; lvl++)
203 			parent_idx = psci_non_cpu_pd_nodes[parent_idx].parent_node;
204 
205 		/* Get the non cpu power domain stats */
206 		*psci_stat = psci_non_cpu_stat[parent_idx][stat_idx];
207 	} else {
208 		/* Get the cpu power domain stats */
209 		*psci_stat = psci_cpu_stat[target_idx][stat_idx];
210 	}
211 
212 	return PSCI_E_SUCCESS;
213 }
214 
215 /* This is the top level function for PSCI_STAT_RESIDENCY SMC. */
psci_stat_residency(u_register_t target_cpu,unsigned int power_state)216 u_register_t psci_stat_residency(u_register_t target_cpu,
217 		unsigned int power_state)
218 {
219 	psci_stat_t psci_stat;
220 	int rc = psci_get_stat(target_cpu, power_state, &psci_stat);
221 
222 	if (rc == PSCI_E_SUCCESS)
223 		return psci_stat.residency;
224 	else
225 		return 0;
226 }
227 
228 /* This is the top level function for PSCI_STAT_COUNT SMC. */
psci_stat_count(u_register_t target_cpu,unsigned int power_state)229 u_register_t psci_stat_count(u_register_t target_cpu,
230 	unsigned int power_state)
231 {
232 	psci_stat_t psci_stat;
233 	int rc = psci_get_stat(target_cpu, power_state, &psci_stat);
234 
235 	if (rc == PSCI_E_SUCCESS)
236 		return psci_stat.count;
237 	else
238 		return 0;
239 }
240