1 /*
2  * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <errno.h>
9 
10 #include <platform_def.h>
11 
12 #include <arch_helpers.h>
13 #include <bl32/sp_min/platform_sp_min.h>
14 #include <common/debug.h>
15 #include <drivers/arm/gic_common.h>
16 #include <drivers/arm/gicv2.h>
17 #include <drivers/st/stm32mp1_clk.h>
18 #include <dt-bindings/clock/stm32mp1-clks.h>
19 #include <lib/mmio.h>
20 #include <lib/psci/psci.h>
21 #include <plat/common/platform.h>
22 
23 static uintptr_t stm32_sec_entrypoint;
24 static uint32_t cntfrq_core0;
25 
26 /*******************************************************************************
27  * STM32MP1 handler called when a CPU is about to enter standby.
28  * call by core 1 to enter in wfi
29  ******************************************************************************/
stm32_cpu_standby(plat_local_state_t cpu_state)30 static void stm32_cpu_standby(plat_local_state_t cpu_state)
31 {
32 	uint32_t interrupt = GIC_SPURIOUS_INTERRUPT;
33 
34 	assert(cpu_state == ARM_LOCAL_STATE_RET);
35 
36 	/*
37 	 * Enter standby state
38 	 * dsb is good practice before using wfi to enter low power states
39 	 */
40 	isb();
41 	dsb();
42 	while (interrupt == GIC_SPURIOUS_INTERRUPT) {
43 		wfi();
44 
45 		/* Acknoledge IT */
46 		interrupt = gicv2_acknowledge_interrupt();
47 		/* If Interrupt == 1022 it will be acknowledged by non secure */
48 		if ((interrupt != PENDING_G1_INTID) &&
49 		    (interrupt != GIC_SPURIOUS_INTERRUPT)) {
50 			gicv2_end_of_interrupt(interrupt);
51 		}
52 	}
53 }
54 
55 /*******************************************************************************
56  * STM32MP1 handler called when a power domain is about to be turned on. The
57  * mpidr determines the CPU to be turned on.
58  * call by core 0 to activate core 1
59  ******************************************************************************/
stm32_pwr_domain_on(u_register_t mpidr)60 static int stm32_pwr_domain_on(u_register_t mpidr)
61 {
62 	unsigned long current_cpu_mpidr = read_mpidr_el1();
63 	uint32_t bkpr_core1_addr =
64 		tamp_bkpr(BOOT_API_CORE1_BRANCH_ADDRESS_TAMP_BCK_REG_IDX);
65 	uint32_t bkpr_core1_magic =
66 		tamp_bkpr(BOOT_API_CORE1_MAGIC_NUMBER_TAMP_BCK_REG_IDX);
67 
68 	if (mpidr == current_cpu_mpidr) {
69 		return PSCI_E_INVALID_PARAMS;
70 	}
71 
72 	/* Only one valid entry point */
73 	if (stm32_sec_entrypoint != (uintptr_t)&sp_min_warm_entrypoint) {
74 		return PSCI_E_INVALID_ADDRESS;
75 	}
76 
77 	stm32mp_clk_enable(RTCAPB);
78 
79 	cntfrq_core0 = read_cntfrq_el0();
80 
81 	/* Write entrypoint in backup RAM register */
82 	mmio_write_32(bkpr_core1_addr, stm32_sec_entrypoint);
83 
84 	/* Write magic number in backup register */
85 	mmio_write_32(bkpr_core1_magic, BOOT_API_A7_CORE1_MAGIC_NUMBER);
86 
87 	stm32mp_clk_disable(RTCAPB);
88 
89 	/* Generate an IT to core 1 */
90 	gicv2_raise_sgi(ARM_IRQ_SEC_SGI_0, STM32MP_SECONDARY_CPU);
91 
92 	return PSCI_E_SUCCESS;
93 }
94 
95 /*******************************************************************************
96  * STM32MP1 handler called when a power domain is about to be turned off. The
97  * target_state encodes the power state that each level should transition to.
98  ******************************************************************************/
stm32_pwr_domain_off(const psci_power_state_t * target_state)99 static void stm32_pwr_domain_off(const psci_power_state_t *target_state)
100 {
101 	/* Nothing to do */
102 }
103 
104 /*******************************************************************************
105  * STM32MP1 handler called when a power domain is about to be suspended. The
106  * target_state encodes the power state that each level should transition to.
107  ******************************************************************************/
stm32_pwr_domain_suspend(const psci_power_state_t * target_state)108 static void stm32_pwr_domain_suspend(const psci_power_state_t *target_state)
109 {
110 	/* Nothing to do, power domain is not disabled */
111 }
112 
113 /*******************************************************************************
114  * STM32MP1 handler called when a power domain has just been powered on after
115  * being turned off earlier. The target_state encodes the low power state that
116  * each level has woken up from.
117  * call by core 1 just after wake up
118  ******************************************************************************/
stm32_pwr_domain_on_finish(const psci_power_state_t * target_state)119 static void stm32_pwr_domain_on_finish(const psci_power_state_t *target_state)
120 {
121 	stm32mp1_gic_pcpu_init();
122 
123 	write_cntfrq_el0(cntfrq_core0);
124 }
125 
126 /*******************************************************************************
127  * STM32MP1 handler called when a power domain has just been powered on after
128  * having been suspended earlier. The target_state encodes the low power state
129  * that each level has woken up from.
130  ******************************************************************************/
stm32_pwr_domain_suspend_finish(const psci_power_state_t * target_state)131 static void stm32_pwr_domain_suspend_finish(const psci_power_state_t
132 					    *target_state)
133 {
134 	/* Nothing to do, power domain is not disabled */
135 }
136 
stm32_pwr_domain_pwr_down_wfi(const psci_power_state_t * target_state)137 static void __dead2 stm32_pwr_domain_pwr_down_wfi(const psci_power_state_t
138 						  *target_state)
139 {
140 	ERROR("stm32mpu1 Power Down WFI: operation not handled.\n");
141 	panic();
142 }
143 
stm32_system_off(void)144 static void __dead2 stm32_system_off(void)
145 {
146 	ERROR("stm32mpu1 System Off: operation not handled.\n");
147 	panic();
148 }
149 
stm32_system_reset(void)150 static void __dead2 stm32_system_reset(void)
151 {
152 	mmio_setbits_32(stm32mp_rcc_base() + RCC_MP_GRSTCSETR,
153 			RCC_MP_GRSTCSETR_MPSYSRST);
154 
155 	/* Loop in case system reset is not immediately caught */
156 	for ( ; ; ) {
157 		;
158 	}
159 }
160 
stm32_validate_power_state(unsigned int power_state,psci_power_state_t * req_state)161 static int stm32_validate_power_state(unsigned int power_state,
162 				      psci_power_state_t *req_state)
163 {
164 	int pstate = psci_get_pstate_type(power_state);
165 
166 	if (pstate != 0) {
167 		return PSCI_E_INVALID_PARAMS;
168 	}
169 
170 	if (psci_get_pstate_pwrlvl(power_state)) {
171 		return PSCI_E_INVALID_PARAMS;
172 	}
173 
174 	if (psci_get_pstate_id(power_state)) {
175 		return PSCI_E_INVALID_PARAMS;
176 	}
177 
178 	req_state->pwr_domain_state[0] = ARM_LOCAL_STATE_RET;
179 	req_state->pwr_domain_state[1] = ARM_LOCAL_STATE_RUN;
180 
181 	return PSCI_E_SUCCESS;
182 }
183 
stm32_validate_ns_entrypoint(uintptr_t entrypoint)184 static int stm32_validate_ns_entrypoint(uintptr_t entrypoint)
185 {
186 	/* The non-secure entry point must be in DDR */
187 	if (entrypoint < STM32MP_DDR_BASE) {
188 		return PSCI_E_INVALID_ADDRESS;
189 	}
190 
191 	return PSCI_E_SUCCESS;
192 }
193 
stm32_node_hw_state(u_register_t target_cpu,unsigned int power_level)194 static int stm32_node_hw_state(u_register_t target_cpu,
195 			       unsigned int power_level)
196 {
197 	/*
198 	 * The format of 'power_level' is implementation-defined, but 0 must
199 	 * mean a CPU. Only allow level 0.
200 	 */
201 	if (power_level != MPIDR_AFFLVL0) {
202 		return PSCI_E_INVALID_PARAMS;
203 	}
204 
205 	/*
206 	 * From psci view the CPU 0 is always ON,
207 	 * CPU 1 can be SUSPEND or RUNNING.
208 	 * Therefore do not manage POWER OFF state and always return HW_ON.
209 	 */
210 
211 	return (int)HW_ON;
212 }
213 
214 /*******************************************************************************
215  * Export the platform handlers. The ARM Standard platform layer will take care
216  * of registering the handlers with PSCI.
217  ******************************************************************************/
218 static const plat_psci_ops_t stm32_psci_ops = {
219 	.cpu_standby = stm32_cpu_standby,
220 	.pwr_domain_on = stm32_pwr_domain_on,
221 	.pwr_domain_off = stm32_pwr_domain_off,
222 	.pwr_domain_suspend = stm32_pwr_domain_suspend,
223 	.pwr_domain_on_finish = stm32_pwr_domain_on_finish,
224 	.pwr_domain_suspend_finish = stm32_pwr_domain_suspend_finish,
225 	.pwr_domain_pwr_down_wfi = stm32_pwr_domain_pwr_down_wfi,
226 	.system_off = stm32_system_off,
227 	.system_reset = stm32_system_reset,
228 	.validate_power_state = stm32_validate_power_state,
229 	.validate_ns_entrypoint = stm32_validate_ns_entrypoint,
230 	.get_node_hw_state = stm32_node_hw_state
231 };
232 
233 /*******************************************************************************
234  * Export the platform specific power ops.
235  ******************************************************************************/
plat_setup_psci_ops(uintptr_t sec_entrypoint,const plat_psci_ops_t ** psci_ops)236 int plat_setup_psci_ops(uintptr_t sec_entrypoint,
237 			const plat_psci_ops_t **psci_ops)
238 {
239 	stm32_sec_entrypoint = sec_entrypoint;
240 	*psci_ops = &stm32_psci_ops;
241 
242 	return 0;
243 }
244