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1 /*
2  * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <arch_helpers.h>
8 #include <arm_config.h>
9 #include <assert.h>
10 #include <debug.h>
11 #include <errno.h>
12 #include <gicv3.h>
13 #include <mmio.h>
14 #include <plat_arm.h>
15 #include <platform.h>
16 #include <psci.h>
17 #include <v2m_def.h>
18 #include "drivers/pwrc/fvp_pwrc.h"
19 #include "fvp_def.h"
20 #include "fvp_private.h"
21 
22 
23 #if ARM_RECOM_STATE_ID_ENC
24 /*
25  *  The table storing the valid idle power states. Ensure that the
26  *  array entries are populated in ascending order of state-id to
27  *  enable us to use binary search during power state validation.
28  *  The table must be terminated by a NULL entry.
29  */
30 const unsigned int arm_pm_idle_states[] = {
31 	/* State-id - 0x01 */
32 	arm_make_pwrstate_lvl1(ARM_LOCAL_STATE_RUN, ARM_LOCAL_STATE_RET,
33 			ARM_PWR_LVL0, PSTATE_TYPE_STANDBY),
34 	/* State-id - 0x02 */
35 	arm_make_pwrstate_lvl1(ARM_LOCAL_STATE_RUN, ARM_LOCAL_STATE_OFF,
36 			ARM_PWR_LVL0, PSTATE_TYPE_POWERDOWN),
37 	/* State-id - 0x22 */
38 	arm_make_pwrstate_lvl1(ARM_LOCAL_STATE_OFF, ARM_LOCAL_STATE_OFF,
39 			ARM_PWR_LVL1, PSTATE_TYPE_POWERDOWN),
40 	/* State-id - 0x222 */
41 	arm_make_pwrstate_lvl2(ARM_LOCAL_STATE_OFF, ARM_LOCAL_STATE_OFF,
42 		ARM_LOCAL_STATE_OFF, ARM_PWR_LVL2, PSTATE_TYPE_POWERDOWN),
43 	0,
44 };
45 #endif
46 
47 /*******************************************************************************
48  * Function which implements the common FVP specific operations to power down a
49  * cluster in response to a CPU_OFF or CPU_SUSPEND request.
50  ******************************************************************************/
fvp_cluster_pwrdwn_common(void)51 static void fvp_cluster_pwrdwn_common(void)
52 {
53 	uint64_t mpidr = read_mpidr_el1();
54 
55 #if ENABLE_SPE_FOR_LOWER_ELS
56 	/*
57 	 * On power down we need to disable statistical profiling extensions
58 	 * before exiting coherency.
59 	 */
60 	arm_disable_spe();
61 #endif
62 
63 	/* Disable coherency if this cluster is to be turned off */
64 	fvp_interconnect_disable();
65 
66 	/* Program the power controller to turn the cluster off */
67 	fvp_pwrc_write_pcoffr(mpidr);
68 }
69 
70 /*
71  * Empty implementation of these hooks avoid setting the GICR_WAKER.Sleep bit
72  * on ARM GICv3 implementations on FVP. This is required, because FVP does not
73  * support SYSTEM_SUSPEND and it is `faked` in firmware. Hence, for wake up
74  * from `fake` system suspend the GIC must not be powered off.
75  */
arm_gicv3_distif_pre_save(unsigned int proc_num)76 void arm_gicv3_distif_pre_save(unsigned int proc_num)
77 {}
78 
arm_gicv3_distif_post_restore(unsigned int proc_num)79 void arm_gicv3_distif_post_restore(unsigned int proc_num)
80 {}
81 
fvp_power_domain_on_finish_common(const psci_power_state_t * target_state)82 static void fvp_power_domain_on_finish_common(const psci_power_state_t *target_state)
83 {
84 	unsigned long mpidr;
85 
86 	assert(target_state->pwr_domain_state[ARM_PWR_LVL0] ==
87 					ARM_LOCAL_STATE_OFF);
88 
89 	/* Get the mpidr for this cpu */
90 	mpidr = read_mpidr_el1();
91 
92 	/* Perform the common cluster specific operations */
93 	if (target_state->pwr_domain_state[ARM_PWR_LVL1] ==
94 					ARM_LOCAL_STATE_OFF) {
95 		/*
96 		 * This CPU might have woken up whilst the cluster was
97 		 * attempting to power down. In this case the FVP power
98 		 * controller will have a pending cluster power off request
99 		 * which needs to be cleared by writing to the PPONR register.
100 		 * This prevents the power controller from interpreting a
101 		 * subsequent entry of this cpu into a simple wfi as a power
102 		 * down request.
103 		 */
104 		fvp_pwrc_write_pponr(mpidr);
105 
106 		/* Enable coherency if this cluster was off */
107 		fvp_interconnect_enable();
108 	}
109 	/* Perform the common system specific operations */
110 	if (target_state->pwr_domain_state[ARM_PWR_LVL2] ==
111 						ARM_LOCAL_STATE_OFF)
112 		arm_system_pwr_domain_resume();
113 
114 	/*
115 	 * Clear PWKUPR.WEN bit to ensure interrupts do not interfere
116 	 * with a cpu power down unless the bit is set again
117 	 */
118 	fvp_pwrc_clr_wen(mpidr);
119 }
120 
121 
122 /*******************************************************************************
123  * FVP handler called when a CPU is about to enter standby.
124  ******************************************************************************/
fvp_cpu_standby(plat_local_state_t cpu_state)125 void fvp_cpu_standby(plat_local_state_t cpu_state)
126 {
127 
128 	assert(cpu_state == ARM_LOCAL_STATE_RET);
129 
130 	/*
131 	 * Enter standby state
132 	 * dsb is good practice before using wfi to enter low power states
133 	 */
134 	dsb();
135 	wfi();
136 }
137 
138 /*******************************************************************************
139  * FVP handler called when a power domain is about to be turned on. The
140  * mpidr determines the CPU to be turned on.
141  ******************************************************************************/
fvp_pwr_domain_on(u_register_t mpidr)142 int fvp_pwr_domain_on(u_register_t mpidr)
143 {
144 	int rc = PSCI_E_SUCCESS;
145 	unsigned int psysr;
146 
147 	/*
148 	 * Ensure that we do not cancel an inflight power off request for the
149 	 * target cpu. That would leave it in a zombie wfi. Wait for it to power
150 	 * off and then program the power controller to turn that CPU on.
151 	 */
152 	do {
153 		psysr = fvp_pwrc_read_psysr(mpidr);
154 	} while (psysr & PSYSR_AFF_L0);
155 
156 	fvp_pwrc_write_pponr(mpidr);
157 	return rc;
158 }
159 
160 /*******************************************************************************
161  * FVP handler called when a power domain is about to be turned off. The
162  * target_state encodes the power state that each level should transition to.
163  ******************************************************************************/
fvp_pwr_domain_off(const psci_power_state_t * target_state)164 void fvp_pwr_domain_off(const psci_power_state_t *target_state)
165 {
166 	assert(target_state->pwr_domain_state[ARM_PWR_LVL0] ==
167 					ARM_LOCAL_STATE_OFF);
168 
169 	/*
170 	 * If execution reaches this stage then this power domain will be
171 	 * suspended. Perform at least the cpu specific actions followed
172 	 * by the cluster specific operations if applicable.
173 	 */
174 
175 	/* Prevent interrupts from spuriously waking up this cpu */
176 	plat_arm_gic_cpuif_disable();
177 
178 	/* Turn redistributor off */
179 	plat_arm_gic_redistif_off();
180 
181 	/* Program the power controller to power off this cpu. */
182 	fvp_pwrc_write_ppoffr(read_mpidr_el1());
183 
184 	if (target_state->pwr_domain_state[ARM_PWR_LVL1] ==
185 					ARM_LOCAL_STATE_OFF)
186 		fvp_cluster_pwrdwn_common();
187 
188 }
189 
190 /*******************************************************************************
191  * FVP handler called when a power domain is about to be suspended. The
192  * target_state encodes the power state that each level should transition to.
193  ******************************************************************************/
fvp_pwr_domain_suspend(const psci_power_state_t * target_state)194 void fvp_pwr_domain_suspend(const psci_power_state_t *target_state)
195 {
196 	unsigned long mpidr;
197 
198 	/*
199 	 * FVP has retention only at cpu level. Just return
200 	 * as nothing is to be done for retention.
201 	 */
202 	if (target_state->pwr_domain_state[ARM_PWR_LVL0] ==
203 					ARM_LOCAL_STATE_RET)
204 		return;
205 
206 	assert(target_state->pwr_domain_state[ARM_PWR_LVL0] ==
207 					ARM_LOCAL_STATE_OFF);
208 
209 	/* Get the mpidr for this cpu */
210 	mpidr = read_mpidr_el1();
211 
212 	/* Program the power controller to enable wakeup interrupts. */
213 	fvp_pwrc_set_wen(mpidr);
214 
215 	/* Prevent interrupts from spuriously waking up this cpu */
216 	plat_arm_gic_cpuif_disable();
217 
218 	/*
219 	 * The Redistributor is not powered off as it can potentially prevent
220 	 * wake up events reaching the CPUIF and/or might lead to losing
221 	 * register context.
222 	 */
223 
224 	/* Perform the common cluster specific operations */
225 	if (target_state->pwr_domain_state[ARM_PWR_LVL1] ==
226 					ARM_LOCAL_STATE_OFF)
227 		fvp_cluster_pwrdwn_common();
228 
229 	/* Perform the common system specific operations */
230 	if (target_state->pwr_domain_state[ARM_PWR_LVL2] ==
231 						ARM_LOCAL_STATE_OFF)
232 		arm_system_pwr_domain_save();
233 
234 	/* Program the power controller to power off this cpu. */
235 	fvp_pwrc_write_ppoffr(read_mpidr_el1());
236 }
237 
238 /*******************************************************************************
239  * FVP handler called when a power domain has just been powered on after
240  * being turned off earlier. The target_state encodes the low power state that
241  * each level has woken up from.
242  ******************************************************************************/
fvp_pwr_domain_on_finish(const psci_power_state_t * target_state)243 void fvp_pwr_domain_on_finish(const psci_power_state_t *target_state)
244 {
245 	fvp_power_domain_on_finish_common(target_state);
246 
247 	/* Enable the gic cpu interface */
248 	plat_arm_gic_pcpu_init();
249 
250 	/* Program the gic per-cpu distributor or re-distributor interface */
251 	plat_arm_gic_cpuif_enable();
252 }
253 
254 /*******************************************************************************
255  * FVP handler called when a power domain has just been powered on after
256  * having been suspended earlier. The target_state encodes the low power state
257  * that each level has woken up from.
258  * TODO: At the moment we reuse the on finisher and reinitialize the secure
259  * context. Need to implement a separate suspend finisher.
260  ******************************************************************************/
fvp_pwr_domain_suspend_finish(const psci_power_state_t * target_state)261 void fvp_pwr_domain_suspend_finish(const psci_power_state_t *target_state)
262 {
263 	/*
264 	 * Nothing to be done on waking up from retention from CPU level.
265 	 */
266 	if (target_state->pwr_domain_state[ARM_PWR_LVL0] ==
267 					ARM_LOCAL_STATE_RET)
268 		return;
269 
270 	fvp_power_domain_on_finish_common(target_state);
271 
272 	/* Enable the gic cpu interface */
273 	plat_arm_gic_cpuif_enable();
274 }
275 
276 /*******************************************************************************
277  * FVP handlers to shutdown/reboot the system
278  ******************************************************************************/
fvp_system_off(void)279 static void __dead2 fvp_system_off(void)
280 {
281 	/* Write the System Configuration Control Register */
282 	mmio_write_32(V2M_SYSREGS_BASE + V2M_SYS_CFGCTRL,
283 		V2M_CFGCTRL_START |
284 		V2M_CFGCTRL_RW |
285 		V2M_CFGCTRL_FUNC(V2M_FUNC_SHUTDOWN));
286 	wfi();
287 	ERROR("FVP System Off: operation not handled.\n");
288 	panic();
289 }
290 
fvp_system_reset(void)291 static void __dead2 fvp_system_reset(void)
292 {
293 	/* Write the System Configuration Control Register */
294 	mmio_write_32(V2M_SYSREGS_BASE + V2M_SYS_CFGCTRL,
295 		V2M_CFGCTRL_START |
296 		V2M_CFGCTRL_RW |
297 		V2M_CFGCTRL_FUNC(V2M_FUNC_REBOOT));
298 	wfi();
299 	ERROR("FVP System Reset: operation not handled.\n");
300 	panic();
301 }
302 
fvp_node_hw_state(u_register_t target_cpu,unsigned int power_level)303 static int fvp_node_hw_state(u_register_t target_cpu,
304 			     unsigned int power_level)
305 {
306 	unsigned int psysr;
307 	int ret;
308 
309 	/*
310 	 * The format of 'power_level' is implementation-defined, but 0 must
311 	 * mean a CPU. We also allow 1 to denote the cluster
312 	 */
313 	if (power_level != ARM_PWR_LVL0 && power_level != ARM_PWR_LVL1)
314 		return PSCI_E_INVALID_PARAMS;
315 
316 	/*
317 	 * Read the status of the given MPDIR from FVP power controller. The
318 	 * power controller only gives us on/off status, so map that to expected
319 	 * return values of the PSCI call
320 	 */
321 	psysr = fvp_pwrc_read_psysr(target_cpu);
322 	if (psysr == PSYSR_INVALID)
323 		return PSCI_E_INVALID_PARAMS;
324 
325 	switch (power_level) {
326 	case ARM_PWR_LVL0:
327 		ret = (psysr & PSYSR_AFF_L0) ? HW_ON : HW_OFF;
328 		break;
329 	case ARM_PWR_LVL1:
330 		ret = (psysr & PSYSR_AFF_L1) ? HW_ON : HW_OFF;
331 		break;
332 	}
333 
334 	return ret;
335 }
336 
337 /*
338  * The FVP doesn't truly support power management at SYSTEM power domain. The
339  * SYSTEM_SUSPEND will be down-graded to the cluster level within the platform
340  * layer. The `fake` SYSTEM_SUSPEND allows us to validate some of the driver
341  * save and restore sequences on FVP.
342  */
fvp_get_sys_suspend_power_state(psci_power_state_t * req_state)343 void fvp_get_sys_suspend_power_state(psci_power_state_t *req_state)
344 {
345 	unsigned int i;
346 
347 	for (i = ARM_PWR_LVL0; i <= PLAT_MAX_PWR_LVL; i++)
348 		req_state->pwr_domain_state[i] = ARM_LOCAL_STATE_OFF;
349 }
350 
351 /*******************************************************************************
352  * Handler to filter PSCI requests.
353  ******************************************************************************/
354 /*
355  * The system power domain suspend is only supported only via
356  * PSCI SYSTEM_SUSPEND API. PSCI CPU_SUSPEND request to system power domain
357  * will be downgraded to the lower level.
358  */
fvp_validate_power_state(unsigned int power_state,psci_power_state_t * req_state)359 static int fvp_validate_power_state(unsigned int power_state,
360 			    psci_power_state_t *req_state)
361 {
362 	int rc;
363 	rc = arm_validate_power_state(power_state, req_state);
364 
365 	/*
366 	 * Ensure that the system power domain level is never suspended
367 	 * via PSCI CPU SUSPEND API. Currently system suspend is only
368 	 * supported via PSCI SYSTEM SUSPEND API.
369 	 */
370 	req_state->pwr_domain_state[ARM_PWR_LVL2] = ARM_LOCAL_STATE_RUN;
371 	return rc;
372 }
373 
374 /*
375  * Custom `translate_power_state_by_mpidr` handler for FVP. Unlike in the
376  * `fvp_validate_power_state`, we do not downgrade the system power
377  * domain level request in `power_state` as it will be used to query the
378  * PSCI_STAT_COUNT/RESIDENCY at the system power domain level.
379  */
fvp_translate_power_state_by_mpidr(u_register_t mpidr,unsigned int power_state,psci_power_state_t * output_state)380 static int fvp_translate_power_state_by_mpidr(u_register_t mpidr,
381 		unsigned int power_state,
382 		psci_power_state_t *output_state)
383 {
384 	return arm_validate_power_state(power_state, output_state);
385 }
386 
387 /*******************************************************************************
388  * Export the platform handlers via plat_arm_psci_pm_ops. The ARM Standard
389  * platform layer will take care of registering the handlers with PSCI.
390  ******************************************************************************/
391 plat_psci_ops_t plat_arm_psci_pm_ops = {
392 	.cpu_standby = fvp_cpu_standby,
393 	.pwr_domain_on = fvp_pwr_domain_on,
394 	.pwr_domain_off = fvp_pwr_domain_off,
395 	.pwr_domain_suspend = fvp_pwr_domain_suspend,
396 	.pwr_domain_on_finish = fvp_pwr_domain_on_finish,
397 	.pwr_domain_suspend_finish = fvp_pwr_domain_suspend_finish,
398 	.system_off = fvp_system_off,
399 	.system_reset = fvp_system_reset,
400 	.validate_power_state = fvp_validate_power_state,
401 	.validate_ns_entrypoint = arm_validate_ns_entrypoint,
402 	.translate_power_state_by_mpidr = fvp_translate_power_state_by_mpidr,
403 	.get_node_hw_state = fvp_node_hw_state,
404 	.get_sys_suspend_power_state = fvp_get_sys_suspend_power_state,
405 /*
406  * mem_protect is not supported in RESET_TO_BL31 and RESET_TO_SP_MIN,
407  * as that would require mapping in all of NS DRAM into BL31 or BL32.
408  */
409 #if !RESET_TO_BL31 && !RESET_TO_SP_MIN
410 	.mem_protect_chk	= arm_psci_mem_protect_chk,
411 	.read_mem_protect	= arm_psci_read_mem_protect,
412 	.write_mem_protect	= arm_nor_psci_write_mem_protect,
413 #endif
414 };
415