1 /*
2  * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <arch_helpers.h>
8 #include <assert.h>
9 #include <cassert.h>
10 #include <css_pm.h>
11 #include <debug.h>
12 #include <errno.h>
13 #include <plat_arm.h>
14 #include <platform.h>
15 #include <platform_def.h>
16 #include "../drivers/scp/css_scp.h"
17 
18 /* Allow CSS platforms to override `plat_arm_psci_pm_ops` */
19 #pragma weak plat_arm_psci_pm_ops
20 
21 #if ARM_RECOM_STATE_ID_ENC
22 /*
23  *  The table storing the valid idle power states. Ensure that the
24  *  array entries are populated in ascending order of state-id to
25  *  enable us to use binary search during power state validation.
26  *  The table must be terminated by a NULL entry.
27  */
28 const unsigned int arm_pm_idle_states[] = {
29 	/* State-id - 0x001 */
30 	arm_make_pwrstate_lvl2(ARM_LOCAL_STATE_RUN, ARM_LOCAL_STATE_RUN,
31 		ARM_LOCAL_STATE_RET, ARM_PWR_LVL0, PSTATE_TYPE_STANDBY),
32 	/* State-id - 0x002 */
33 	arm_make_pwrstate_lvl2(ARM_LOCAL_STATE_RUN, ARM_LOCAL_STATE_RUN,
34 		ARM_LOCAL_STATE_OFF, ARM_PWR_LVL0, PSTATE_TYPE_POWERDOWN),
35 	/* State-id - 0x022 */
36 	arm_make_pwrstate_lvl2(ARM_LOCAL_STATE_RUN, ARM_LOCAL_STATE_OFF,
37 		ARM_LOCAL_STATE_OFF, ARM_PWR_LVL1, PSTATE_TYPE_POWERDOWN),
38 #if PLAT_MAX_PWR_LVL > ARM_PWR_LVL1
39 	/* State-id - 0x222 */
40 	arm_make_pwrstate_lvl2(ARM_LOCAL_STATE_OFF, ARM_LOCAL_STATE_OFF,
41 		ARM_LOCAL_STATE_OFF, ARM_PWR_LVL2, PSTATE_TYPE_POWERDOWN),
42 #endif
43 	0,
44 };
45 #endif /* __ARM_RECOM_STATE_ID_ENC__ */
46 
47 /*
48  * All the power management helpers in this file assume at least cluster power
49  * level is supported.
50  */
51 CASSERT(PLAT_MAX_PWR_LVL >= ARM_PWR_LVL1,
52 		assert_max_pwr_lvl_supported_mismatch);
53 
54 /*
55  * Ensure that the PLAT_MAX_PWR_LVL is not greater than CSS_SYSTEM_PWR_DMN_LVL
56  * assumed by the CSS layer.
57  */
58 CASSERT(PLAT_MAX_PWR_LVL <= CSS_SYSTEM_PWR_DMN_LVL,
59 		assert_max_pwr_lvl_higher_than_css_sys_lvl);
60 
61 /*******************************************************************************
62  * Handler called when a power domain is about to be turned on. The
63  * level and mpidr determine the affinity instance.
64  ******************************************************************************/
css_pwr_domain_on(u_register_t mpidr)65 int css_pwr_domain_on(u_register_t mpidr)
66 {
67 	css_scp_on(mpidr);
68 
69 	return PSCI_E_SUCCESS;
70 }
71 
css_pwr_domain_on_finisher_common(const psci_power_state_t * target_state)72 static void css_pwr_domain_on_finisher_common(
73 		const psci_power_state_t *target_state)
74 {
75 	assert(CSS_CORE_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF);
76 
77 	/* Enable the gic cpu interface */
78 	plat_arm_gic_cpuif_enable();
79 
80 	/*
81 	 * Perform the common cluster specific operations i.e enable coherency
82 	 * if this cluster was off.
83 	 */
84 	if (CSS_CLUSTER_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF)
85 		plat_arm_interconnect_enter_coherency();
86 }
87 
88 /*******************************************************************************
89  * Handler called when a power level has just been powered on after
90  * being turned off earlier. The target_state encodes the low power state that
91  * each level has woken up from. This handler would never be invoked with
92  * the system power domain uninitialized as either the primary would have taken
93  * care of it as part of cold boot or the first core awakened from system
94  * suspend would have already initialized it.
95  ******************************************************************************/
css_pwr_domain_on_finish(const psci_power_state_t * target_state)96 void css_pwr_domain_on_finish(const psci_power_state_t *target_state)
97 {
98 	/* Assert that the system power domain need not be initialized */
99 	assert(CSS_SYSTEM_PWR_STATE(target_state) == ARM_LOCAL_STATE_RUN);
100 
101 	/* Program the gic per-cpu distributor or re-distributor interface */
102 	plat_arm_gic_pcpu_init();
103 
104 	css_pwr_domain_on_finisher_common(target_state);
105 }
106 
107 /*******************************************************************************
108  * Common function called while turning a cpu off or suspending it. It is called
109  * from css_off() or css_suspend() when these functions in turn are called for
110  * power domain at the highest power level which will be powered down. It
111  * performs the actions common to the OFF and SUSPEND calls.
112  ******************************************************************************/
css_power_down_common(const psci_power_state_t * target_state)113 static void css_power_down_common(const psci_power_state_t *target_state)
114 {
115 	/* Prevent interrupts from spuriously waking up this cpu */
116 	plat_arm_gic_cpuif_disable();
117 
118 	/* Cluster is to be turned off, so disable coherency */
119 	if (CSS_CLUSTER_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF)
120 		plat_arm_interconnect_exit_coherency();
121 }
122 
123 /*******************************************************************************
124  * Handler called when a power domain is about to be turned off. The
125  * target_state encodes the power state that each level should transition to.
126  ******************************************************************************/
css_pwr_domain_off(const psci_power_state_t * target_state)127 void css_pwr_domain_off(const psci_power_state_t *target_state)
128 {
129 	assert(CSS_CORE_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF);
130 	css_power_down_common(target_state);
131 	css_scp_off(target_state);
132 }
133 
134 /*******************************************************************************
135  * Handler called when a power domain is about to be suspended. The
136  * target_state encodes the power state that each level should transition to.
137  ******************************************************************************/
css_pwr_domain_suspend(const psci_power_state_t * target_state)138 void css_pwr_domain_suspend(const psci_power_state_t *target_state)
139 {
140 	/*
141 	 * CSS currently supports retention only at cpu level. Just return
142 	 * as nothing is to be done for retention.
143 	 */
144 	if (CSS_CORE_PWR_STATE(target_state) == ARM_LOCAL_STATE_RET)
145 		return;
146 
147 
148 	assert(CSS_CORE_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF);
149 	css_power_down_common(target_state);
150 
151 	/* Perform system domain state saving if issuing system suspend */
152 	if (CSS_SYSTEM_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF) {
153 		arm_system_pwr_domain_save();
154 
155 		/* Power off the Redistributor after having saved its context */
156 		plat_arm_gic_redistif_off();
157 	}
158 
159 	css_scp_suspend(target_state);
160 }
161 
162 /*******************************************************************************
163  * Handler called when a power domain has just been powered on after
164  * having been suspended earlier. The target_state encodes the low power state
165  * that each level has woken up from.
166  * TODO: At the moment we reuse the on finisher and reinitialize the secure
167  * context. Need to implement a separate suspend finisher.
168  ******************************************************************************/
css_pwr_domain_suspend_finish(const psci_power_state_t * target_state)169 void css_pwr_domain_suspend_finish(
170 				const psci_power_state_t *target_state)
171 {
172 	/* Return as nothing is to be done on waking up from retention. */
173 	if (CSS_CORE_PWR_STATE(target_state) == ARM_LOCAL_STATE_RET)
174 		return;
175 
176 	/* Perform system domain restore if woken up from system suspend */
177 	if (CSS_SYSTEM_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF)
178 		/*
179 		 * At this point, the Distributor must be powered on to be ready
180 		 * to have its state restored. The Redistributor will be powered
181 		 * on as part of gicv3_rdistif_init_restore.
182 		 */
183 		arm_system_pwr_domain_resume();
184 
185 	css_pwr_domain_on_finisher_common(target_state);
186 }
187 
188 /*******************************************************************************
189  * Handlers to shutdown/reboot the system
190  ******************************************************************************/
css_system_off(void)191 void __dead2 css_system_off(void)
192 {
193 	css_scp_sys_shutdown();
194 }
195 
css_system_reset(void)196 void __dead2 css_system_reset(void)
197 {
198 	css_scp_sys_reboot();
199 }
200 
201 /*******************************************************************************
202  * Handler called when the CPU power domain is about to enter standby.
203  ******************************************************************************/
css_cpu_standby(plat_local_state_t cpu_state)204 void css_cpu_standby(plat_local_state_t cpu_state)
205 {
206 	unsigned int scr;
207 
208 	assert(cpu_state == ARM_LOCAL_STATE_RET);
209 
210 	scr = read_scr_el3();
211 	/*
212 	 * Enable the Non secure interrupt to wake the CPU.
213 	 * In GICv3 affinity routing mode, the non secure group1 interrupts use
214 	 * the PhysicalFIQ at EL3 whereas in GICv2, it uses the PhysicalIRQ.
215 	 * Enabling both the bits works for both GICv2 mode and GICv3 affinity
216 	 * routing mode.
217 	 */
218 	write_scr_el3(scr | SCR_IRQ_BIT | SCR_FIQ_BIT);
219 	isb();
220 	dsb();
221 	wfi();
222 
223 	/*
224 	 * Restore SCR to the original value, synchronisation of scr_el3 is
225 	 * done by eret while el3_exit to save some execution cycles.
226 	 */
227 	write_scr_el3(scr);
228 }
229 
230 /*******************************************************************************
231  * Handler called to return the 'req_state' for system suspend.
232  ******************************************************************************/
css_get_sys_suspend_power_state(psci_power_state_t * req_state)233 void css_get_sys_suspend_power_state(psci_power_state_t *req_state)
234 {
235 	unsigned int i;
236 
237 	/*
238 	 * System Suspend is supported only if the system power domain node
239 	 * is implemented.
240 	 */
241 	assert(PLAT_MAX_PWR_LVL == CSS_SYSTEM_PWR_DMN_LVL);
242 
243 	for (i = ARM_PWR_LVL0; i <= PLAT_MAX_PWR_LVL; i++)
244 		req_state->pwr_domain_state[i] = ARM_LOCAL_STATE_OFF;
245 }
246 
247 /*******************************************************************************
248  * Handler to query CPU/cluster power states from SCP
249  ******************************************************************************/
css_node_hw_state(u_register_t mpidr,unsigned int power_level)250 int css_node_hw_state(u_register_t mpidr, unsigned int power_level)
251 {
252 	return css_scp_get_power_state(mpidr, power_level);
253 }
254 
255 /*
256  * The system power domain suspend is only supported only via
257  * PSCI SYSTEM_SUSPEND API. PSCI CPU_SUSPEND request to system power domain
258  * will be downgraded to the lower level.
259  */
css_validate_power_state(unsigned int power_state,psci_power_state_t * req_state)260 static int css_validate_power_state(unsigned int power_state,
261 			    psci_power_state_t *req_state)
262 {
263 	int rc;
264 	rc = arm_validate_power_state(power_state, req_state);
265 
266 	/*
267 	 * Ensure that the system power domain level is never suspended
268 	 * via PSCI CPU SUSPEND API. Currently system suspend is only
269 	 * supported via PSCI SYSTEM SUSPEND API.
270 	 */
271 	req_state->pwr_domain_state[CSS_SYSTEM_PWR_DMN_LVL] = ARM_LOCAL_STATE_RUN;
272 	return rc;
273 }
274 
275 /*
276  * Custom `translate_power_state_by_mpidr` handler for CSS. Unlike in the
277  * `css_validate_power_state`, we do not downgrade the system power
278  * domain level request in `power_state` as it will be used to query the
279  * PSCI_STAT_COUNT/RESIDENCY at the system power domain level.
280  */
css_translate_power_state_by_mpidr(u_register_t mpidr,unsigned int power_state,psci_power_state_t * output_state)281 static int css_translate_power_state_by_mpidr(u_register_t mpidr,
282 		unsigned int power_state,
283 		psci_power_state_t *output_state)
284 {
285 	return arm_validate_power_state(power_state, output_state);
286 }
287 
288 /*******************************************************************************
289  * Export the platform handlers via plat_arm_psci_pm_ops. The ARM Standard
290  * platform will take care of registering the handlers with PSCI.
291  ******************************************************************************/
292 plat_psci_ops_t plat_arm_psci_pm_ops = {
293 	.pwr_domain_on		= css_pwr_domain_on,
294 	.pwr_domain_on_finish	= css_pwr_domain_on_finish,
295 	.pwr_domain_off		= css_pwr_domain_off,
296 	.cpu_standby		= css_cpu_standby,
297 	.pwr_domain_suspend	= css_pwr_domain_suspend,
298 	.pwr_domain_suspend_finish	= css_pwr_domain_suspend_finish,
299 	.system_off		= css_system_off,
300 	.system_reset		= css_system_reset,
301 	.validate_power_state	= css_validate_power_state,
302 	.validate_ns_entrypoint = arm_validate_ns_entrypoint,
303 	.translate_power_state_by_mpidr = css_translate_power_state_by_mpidr,
304 	.get_node_hw_state	= css_node_hw_state,
305 	.get_sys_suspend_power_state = css_get_sys_suspend_power_state,
306 /*
307  * mem_protect is not supported in RESET_TO_BL31 and RESET_TO_SP_MIN,
308  * as that would require mapping in all of NS DRAM into BL31 or BL32.
309  */
310 #if defined(PLAT_ARM_MEM_PROT_ADDR) && !RESET_TO_BL31 && !RESET_TO_SP_MIN
311 	.mem_protect_chk	= arm_psci_mem_protect_chk,
312 	.read_mem_protect	= arm_psci_read_mem_protect,
313 	.write_mem_protect	= arm_nor_psci_write_mem_protect,
314 #endif
315 #if CSS_USE_SCMI_SDS_DRIVER
316 	.system_reset2		= css_system_reset2,
317 #endif
318 };
319