1 /*
2  * Copyright (c) 2016-2019, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 
9 #include <platform_def.h>
10 
11 #include <common/debug.h>
12 #include <plat/common/platform.h>
13 
14 #include "psci_private.h"
15 
16 #ifndef PLAT_MAX_PWR_LVL_STATES
17 #define PLAT_MAX_PWR_LVL_STATES		2U
18 #endif
19 
20 /* Following structure is used for PSCI STAT */
21 typedef struct psci_stat {
22 	u_register_t residency;
23 	u_register_t count;
24 } psci_stat_t;
25 
26 /*
27  * Following is used to keep track of the last cpu
28  * that goes to power down in non cpu power domains.
29  */
30 static int last_cpu_in_non_cpu_pd[PSCI_NUM_NON_CPU_PWR_DOMAINS] = {
31 		[0 ... PSCI_NUM_NON_CPU_PWR_DOMAINS - 1U] = -1};
32 
33 /*
34  * Following are used to store PSCI STAT values for
35  * CPU and non CPU power domains.
36  */
37 static psci_stat_t psci_cpu_stat[PLATFORM_CORE_COUNT]
38 				[PLAT_MAX_PWR_LVL_STATES];
39 static psci_stat_t psci_non_cpu_stat[PSCI_NUM_NON_CPU_PWR_DOMAINS]
40 				[PLAT_MAX_PWR_LVL_STATES];
41 
42 /*
43  * This functions returns the index into the `psci_stat_t` array given the
44  * local power state and power domain level. If the platform implements the
45  * `get_pwr_lvl_state_idx` pm hook, then that will be used to return the index.
46  */
get_stat_idx(plat_local_state_t local_state,unsigned int pwr_lvl)47 static int get_stat_idx(plat_local_state_t local_state, unsigned int pwr_lvl)
48 {
49 	int idx;
50 
51 	if (psci_plat_pm_ops->get_pwr_lvl_state_idx == NULL) {
52 		assert(PLAT_MAX_PWR_LVL_STATES == 2U);
53 		if (is_local_state_retn(local_state) != 0)
54 			return 0;
55 
56 		assert(is_local_state_off(local_state) != 0);
57 		return 1;
58 	}
59 
60 	idx = psci_plat_pm_ops->get_pwr_lvl_state_idx(local_state, pwr_lvl);
61 	assert((idx >= 0) && (idx < (int) PLAT_MAX_PWR_LVL_STATES));
62 	return idx;
63 }
64 
65 /*******************************************************************************
66  * This function is passed the target local power states for each power
67  * domain (state_info) between the current CPU domain and its ancestors until
68  * the target power level (end_pwrlvl).
69  *
70  * Then, for each level (apart from the CPU level) until the 'end_pwrlvl', it
71  * updates the `last_cpu_in_non_cpu_pd[]` with last power down cpu id.
72  *
73  * This function will only be invoked with data cache enabled and while
74  * powering down a core.
75  ******************************************************************************/
psci_stats_update_pwr_down(unsigned int end_pwrlvl,const psci_power_state_t * state_info)76 void psci_stats_update_pwr_down(unsigned int end_pwrlvl,
77 			const psci_power_state_t *state_info)
78 {
79 	unsigned int lvl, parent_idx;
80 	unsigned int cpu_idx = plat_my_core_pos();
81 
82 	assert(end_pwrlvl <= PLAT_MAX_PWR_LVL);
83 	assert(state_info != NULL);
84 
85 	parent_idx = psci_cpu_pd_nodes[cpu_idx].parent_node;
86 
87 	for (lvl = PSCI_CPU_PWR_LVL + 1U; lvl <= end_pwrlvl; lvl++) {
88 
89 		/* Break early if the target power state is RUN */
90 		if (is_local_state_run(state_info->pwr_domain_state[lvl]) != 0)
91 			break;
92 
93 		/*
94 		 * The power domain is entering a low power state, so this is
95 		 * the last CPU for this power domain
96 		 */
97 		last_cpu_in_non_cpu_pd[parent_idx] = (int)cpu_idx;
98 
99 		parent_idx = psci_non_cpu_pd_nodes[parent_idx].parent_node;
100 	}
101 
102 }
103 
104 /*******************************************************************************
105  * This function updates the PSCI STATS(residency time and count) for CPU
106  * and NON-CPU power domains.
107  * It is called with caches enabled and locks acquired(for NON-CPU domain)
108  ******************************************************************************/
psci_stats_update_pwr_up(unsigned int end_pwrlvl,const psci_power_state_t * state_info)109 void psci_stats_update_pwr_up(unsigned int end_pwrlvl,
110 			const psci_power_state_t *state_info)
111 {
112 	unsigned int lvl, parent_idx;
113 	unsigned int cpu_idx = plat_my_core_pos();
114 	int stat_idx;
115 	plat_local_state_t local_state;
116 	u_register_t residency;
117 
118 	assert(end_pwrlvl <= PLAT_MAX_PWR_LVL);
119 	assert(state_info != NULL);
120 
121 	/* Get the index into the stats array */
122 	local_state = state_info->pwr_domain_state[PSCI_CPU_PWR_LVL];
123 	stat_idx = get_stat_idx(local_state, PSCI_CPU_PWR_LVL);
124 
125 	/* Call into platform interface to calculate residency. */
126 	residency = plat_psci_stat_get_residency(PSCI_CPU_PWR_LVL,
127 	    state_info, cpu_idx);
128 
129 	/* Update CPU stats. */
130 	psci_cpu_stat[cpu_idx][stat_idx].residency += residency;
131 	psci_cpu_stat[cpu_idx][stat_idx].count++;
132 
133 	/*
134 	 * Check what power domains above CPU were off
135 	 * prior to this CPU powering on.
136 	 */
137 	parent_idx = psci_cpu_pd_nodes[cpu_idx].parent_node;
138 	/* Return early if this is the first power up. */
139 	if (last_cpu_in_non_cpu_pd[parent_idx] == -1)
140 		return;
141 
142 	for (lvl = PSCI_CPU_PWR_LVL + 1U; lvl <= end_pwrlvl; lvl++) {
143 		local_state = state_info->pwr_domain_state[lvl];
144 		if (is_local_state_run(local_state) != 0) {
145 			/* Break early */
146 			break;
147 		}
148 
149 		assert(last_cpu_in_non_cpu_pd[parent_idx] != -1);
150 
151 		/* Call into platform interface to calculate residency. */
152 		residency = plat_psci_stat_get_residency(lvl, state_info,
153 			(unsigned int)last_cpu_in_non_cpu_pd[parent_idx]);
154 
155 		/* Initialize back to reset value */
156 		last_cpu_in_non_cpu_pd[parent_idx] = -1;
157 
158 		/* Get the index into the stats array */
159 		stat_idx = get_stat_idx(local_state, lvl);
160 
161 		/* Update non cpu stats */
162 		psci_non_cpu_stat[parent_idx][stat_idx].residency += residency;
163 		psci_non_cpu_stat[parent_idx][stat_idx].count++;
164 
165 		parent_idx = psci_non_cpu_pd_nodes[parent_idx].parent_node;
166 	}
167 
168 }
169 
170 /*******************************************************************************
171  * This function returns the appropriate count and residency time of the
172  * local state for the highest power level expressed in the `power_state`
173  * for the node represented by `target_cpu`.
174  ******************************************************************************/
psci_get_stat(u_register_t target_cpu,unsigned int power_state,psci_stat_t * psci_stat)175 static int psci_get_stat(u_register_t target_cpu, unsigned int power_state,
176 			 psci_stat_t *psci_stat)
177 {
178 	int rc;
179 	unsigned int pwrlvl, lvl, parent_idx, target_idx;
180 	int stat_idx;
181 	psci_power_state_t state_info = { {PSCI_LOCAL_STATE_RUN} };
182 	plat_local_state_t local_state;
183 
184 	/* Validate the target_cpu parameter and determine the cpu index */
185 	target_idx = (unsigned int) plat_core_pos_by_mpidr(target_cpu);
186 	if (target_idx == (unsigned int) -1)
187 		return PSCI_E_INVALID_PARAMS;
188 
189 	/* Validate the power_state parameter */
190 	if (psci_plat_pm_ops->translate_power_state_by_mpidr == NULL)
191 		rc = psci_validate_power_state(power_state, &state_info);
192 	else
193 		rc = psci_plat_pm_ops->translate_power_state_by_mpidr(
194 				target_cpu, power_state, &state_info);
195 
196 	if (rc != PSCI_E_SUCCESS)
197 		return PSCI_E_INVALID_PARAMS;
198 
199 	/* Find the highest power level */
200 	pwrlvl = psci_find_target_suspend_lvl(&state_info);
201 	if (pwrlvl == PSCI_INVALID_PWR_LVL) {
202 		ERROR("Invalid target power level for PSCI statistics operation\n");
203 		panic();
204 	}
205 
206 	/* Get the index into the stats array */
207 	local_state = state_info.pwr_domain_state[pwrlvl];
208 	stat_idx = get_stat_idx(local_state, pwrlvl);
209 
210 	if (pwrlvl > PSCI_CPU_PWR_LVL) {
211 		/* Get the power domain index */
212 		parent_idx = SPECULATION_SAFE_VALUE(psci_cpu_pd_nodes[target_idx].parent_node);
213 		for (lvl = PSCI_CPU_PWR_LVL + 1U; lvl < pwrlvl; lvl++)
214 			parent_idx = SPECULATION_SAFE_VALUE(psci_non_cpu_pd_nodes[parent_idx].parent_node);
215 
216 		/* Get the non cpu power domain stats */
217 		*psci_stat = psci_non_cpu_stat[parent_idx][stat_idx];
218 	} else {
219 		/* Get the cpu power domain stats */
220 		*psci_stat = psci_cpu_stat[target_idx][stat_idx];
221 	}
222 
223 	return PSCI_E_SUCCESS;
224 }
225 
226 /* This is the top level function for PSCI_STAT_RESIDENCY SMC. */
psci_stat_residency(u_register_t target_cpu,unsigned int power_state)227 u_register_t psci_stat_residency(u_register_t target_cpu,
228 		unsigned int power_state)
229 {
230 	psci_stat_t psci_stat;
231 	int rc = psci_get_stat(target_cpu, power_state, &psci_stat);
232 
233 	if (rc == PSCI_E_SUCCESS)
234 		return psci_stat.residency;
235 	else
236 		return 0;
237 }
238 
239 /* This is the top level function for PSCI_STAT_COUNT SMC. */
psci_stat_count(u_register_t target_cpu,unsigned int power_state)240 u_register_t psci_stat_count(u_register_t target_cpu,
241 	unsigned int power_state)
242 {
243 	psci_stat_t psci_stat;
244 	int rc = psci_get_stat(target_cpu, power_state, &psci_stat);
245 
246 	if (rc == PSCI_E_SUCCESS)
247 		return psci_stat.count;
248 	else
249 		return 0;
250 }
251