xref: /openbmc/u-boot/arch/arm/mach-stm32mp/psci.c (revision 8ee59472)
1 // SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
2 /*
3  * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
4  */
5 
6 #include <config.h>
7 #include <common.h>
8 #include <asm/armv7.h>
9 #include <asm/gic.h>
10 #include <asm/io.h>
11 #include <asm/psci.h>
12 #include <asm/secure.h>
13 
14 #define BOOT_API_A7_CORE0_MAGIC_NUMBER	0xCA7FACE0
15 #define BOOT_API_A7_CORE1_MAGIC_NUMBER	0xCA7FACE1
16 
17 #define MPIDR_AFF0			GENMASK(7, 0)
18 
19 #define RCC_MP_GRSTCSETR		(STM32_RCC_BASE + 0x0404)
20 #define RCC_MP_GRSTCSETR_MPUP1RST	BIT(5)
21 #define RCC_MP_GRSTCSETR_MPUP0RST	BIT(4)
22 #define RCC_MP_GRSTCSETR_MPSYSRST	BIT(0)
23 
24 #define STM32MP1_PSCI_NR_CPUS		2
25 #if STM32MP1_PSCI_NR_CPUS > CONFIG_ARMV7_PSCI_NR_CPUS
26 #error "invalid value for CONFIG_ARMV7_PSCI_NR_CPUS"
27 #endif
28 
29 u8 psci_state[STM32MP1_PSCI_NR_CPUS] __secure_data = {
30 	 PSCI_AFFINITY_LEVEL_ON,
31 	 PSCI_AFFINITY_LEVEL_OFF};
32 
33 void __secure psci_set_state(int cpu, u8 state)
34 {
35 	psci_state[cpu] = state;
36 	dsb();
37 	isb();
38 }
39 
40 static u32 __secure stm32mp_get_gicd_base_address(void)
41 {
42 	u32 periphbase;
43 
44 	/* get the GIC base address from the CBAR register */
45 	asm("mrc p15, 4, %0, c15, c0, 0\n" : "=r" (periphbase));
46 
47 	return (periphbase & CBAR_MASK) + GIC_DIST_OFFSET;
48 }
49 
50 static void __secure stm32mp_smp_kick_all_cpus(void)
51 {
52 	u32 gic_dist_addr;
53 
54 	gic_dist_addr = stm32mp_get_gicd_base_address();
55 
56 	/* kick all CPUs (except this one) by writing to GICD_SGIR */
57 	writel(1U << 24, gic_dist_addr + GICD_SGIR);
58 }
59 
60 void __secure psci_arch_cpu_entry(void)
61 {
62 	u32 cpu = psci_get_cpu_id();
63 
64 	psci_set_state(cpu, PSCI_AFFINITY_LEVEL_ON);
65 }
66 
67 int __secure psci_features(u32 function_id, u32 psci_fid)
68 {
69 	switch (psci_fid) {
70 	case ARM_PSCI_0_2_FN_PSCI_VERSION:
71 	case ARM_PSCI_0_2_FN_CPU_OFF:
72 	case ARM_PSCI_0_2_FN_CPU_ON:
73 	case ARM_PSCI_0_2_FN_AFFINITY_INFO:
74 	case ARM_PSCI_0_2_FN_MIGRATE_INFO_TYPE:
75 	case ARM_PSCI_0_2_FN_SYSTEM_OFF:
76 	case ARM_PSCI_0_2_FN_SYSTEM_RESET:
77 		return 0x0;
78 	}
79 	return ARM_PSCI_RET_NI;
80 }
81 
82 unsigned int __secure psci_version(u32 function_id)
83 {
84 	return ARM_PSCI_VER_1_0;
85 }
86 
87 int __secure psci_affinity_info(u32 function_id, u32 target_affinity,
88 				u32  lowest_affinity_level)
89 {
90 	u32 cpu = target_affinity & MPIDR_AFF0;
91 
92 	if (lowest_affinity_level > 0)
93 		return ARM_PSCI_RET_INVAL;
94 
95 	if (target_affinity & ~MPIDR_AFF0)
96 		return ARM_PSCI_RET_INVAL;
97 
98 	if (cpu >= STM32MP1_PSCI_NR_CPUS)
99 		return ARM_PSCI_RET_INVAL;
100 
101 	return psci_state[cpu];
102 }
103 
104 int __secure psci_migrate_info_type(u32 function_id)
105 {
106 	/* Trusted OS is either not present or does not require migration */
107 	return 2;
108 }
109 
110 int __secure psci_cpu_on(u32 function_id, u32 target_cpu, u32 pc,
111 			 u32 context_id)
112 {
113 	u32 cpu = target_cpu & MPIDR_AFF0;
114 
115 	if (target_cpu & ~MPIDR_AFF0)
116 		return ARM_PSCI_RET_INVAL;
117 
118 	if (cpu >= STM32MP1_PSCI_NR_CPUS)
119 		return ARM_PSCI_RET_INVAL;
120 
121 	if (psci_state[cpu] == PSCI_AFFINITY_LEVEL_ON)
122 		return ARM_PSCI_RET_ALREADY_ON;
123 
124 	/* store target PC and context id*/
125 	psci_save(cpu, pc, context_id);
126 
127 	/* write entrypoint in backup RAM register */
128 	writel((u32)&psci_cpu_entry, TAMP_BACKUP_BRANCH_ADDRESS);
129 	psci_set_state(cpu, PSCI_AFFINITY_LEVEL_ON_PENDING);
130 
131 	/* write magic number in backup register */
132 	if (cpu == 0x01)
133 		writel(BOOT_API_A7_CORE1_MAGIC_NUMBER,
134 		       TAMP_BACKUP_MAGIC_NUMBER);
135 	else
136 		writel(BOOT_API_A7_CORE0_MAGIC_NUMBER,
137 		       TAMP_BACKUP_MAGIC_NUMBER);
138 
139 	stm32mp_smp_kick_all_cpus();
140 
141 	return ARM_PSCI_RET_SUCCESS;
142 }
143 
144 int __secure psci_cpu_off(u32 function_id)
145 {
146 	u32 cpu;
147 
148 	cpu = psci_get_cpu_id();
149 
150 	psci_cpu_off_common();
151 	psci_set_state(cpu, PSCI_AFFINITY_LEVEL_OFF);
152 
153 	/* reset core: wfi is managed by BootRom */
154 	if (cpu == 0x01)
155 		writel(RCC_MP_GRSTCSETR_MPUP1RST, RCC_MP_GRSTCSETR);
156 	else
157 		writel(RCC_MP_GRSTCSETR_MPUP0RST, RCC_MP_GRSTCSETR);
158 
159 	/* just waiting reset */
160 	while (1)
161 		wfi();
162 }
163 
164 void __secure psci_system_reset(u32 function_id)
165 {
166 	/* System reset */
167 	writel(RCC_MP_GRSTCSETR_MPSYSRST, RCC_MP_GRSTCSETR);
168 	/* just waiting reset */
169 	while (1)
170 		wfi();
171 }
172 
173 void __secure psci_system_off(u32 function_id)
174 {
175 	/* System Off is not managed, waiting user power off
176 	 * TODO: handle I2C write in PMIC Main Control register bit 0 = SWOFF
177 	 */
178 	while (1)
179 		wfi();
180 }
181