1 /*
2  * Copyright (c) 2020-2022, 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 #include <inttypes.h>
10 #include <stdint.h>
11 
12 #include <lib/el3_runtime/context_mgmt.h>
13 #include <lib/spinlock.h>
14 #include "spmd_private.h"
15 
16 static struct {
17 	bool secondary_ep_locked;
18 	uintptr_t secondary_ep;
19 	spinlock_t lock;
20 } g_spmd_pm;
21 
22 /*******************************************************************************
23  * spmd_pm_secondary_ep_register
24  ******************************************************************************/
spmd_pm_secondary_ep_register(uintptr_t entry_point)25 int spmd_pm_secondary_ep_register(uintptr_t entry_point)
26 {
27 	int ret = FFA_ERROR_INVALID_PARAMETER;
28 
29 	spin_lock(&g_spmd_pm.lock);
30 
31 	if (g_spmd_pm.secondary_ep_locked == true) {
32 		goto out;
33 	}
34 
35 	/*
36 	 * Check entry_point address is a PA within
37 	 * load_address <= entry_point < load_address + binary_size
38 	 */
39 	if (!spmd_check_address_in_binary_image(entry_point)) {
40 		ERROR("%s entry point is not within image boundaries\n",
41 			__func__);
42 		goto out;
43 	}
44 
45 	g_spmd_pm.secondary_ep = entry_point;
46 	g_spmd_pm.secondary_ep_locked = true;
47 
48 	VERBOSE("%s %lx\n", __func__, entry_point);
49 
50 	ret = 0;
51 
52 out:
53 	spin_unlock(&g_spmd_pm.lock);
54 
55 	return ret;
56 }
57 
58 /*******************************************************************************
59  * This CPU has been turned on. Enter SPMC to initialise S-EL1 or S-EL2. As part
60  * of the SPMC initialization path, they will initialize any SPs that they
61  * manage. Entry into SPMC is done after initialising minimal architectural
62  * state that guarantees safe execution.
63  ******************************************************************************/
spmd_cpu_on_finish_handler(u_register_t unused)64 static void spmd_cpu_on_finish_handler(u_register_t unused)
65 {
66 	spmd_spm_core_context_t *ctx = spmd_get_context();
67 	unsigned int linear_id = plat_my_core_pos();
68 	el3_state_t *el3_state;
69 	uintptr_t entry_point;
70 	uint64_t rc;
71 
72 	assert(ctx != NULL);
73 	assert(ctx->state != SPMC_STATE_ON);
74 
75 	spin_lock(&g_spmd_pm.lock);
76 
77 	/*
78 	 * Leave the possibility that the SPMC does not call
79 	 * FFA_SECONDARY_EP_REGISTER in which case re-use the
80 	 * primary core address for booting secondary cores.
81 	 */
82 	if (g_spmd_pm.secondary_ep_locked == true) {
83 		/*
84 		 * The CPU context has already been initialized at boot time
85 		 * (in spmd_spmc_init by a call to cm_setup_context). Adjust
86 		 * below the target core entry point based on the address
87 		 * passed to by FFA_SECONDARY_EP_REGISTER.
88 		 */
89 		entry_point = g_spmd_pm.secondary_ep;
90 		el3_state = get_el3state_ctx(&ctx->cpu_ctx);
91 		write_ctx_reg(el3_state, CTX_ELR_EL3, entry_point);
92 	}
93 
94 	spin_unlock(&g_spmd_pm.lock);
95 
96 	/* Mark CPU as initiating ON operation. */
97 	ctx->state = SPMC_STATE_ON_PENDING;
98 
99 	rc = spmd_spm_core_sync_entry(ctx);
100 	if (rc != 0ULL) {
101 		ERROR("%s failed (%" PRIu64 ") on CPU%u\n", __func__, rc,
102 			linear_id);
103 		ctx->state = SPMC_STATE_OFF;
104 		return;
105 	}
106 
107 	ctx->state = SPMC_STATE_ON;
108 
109 	VERBOSE("CPU %u on!\n", linear_id);
110 }
111 
112 /*******************************************************************************
113  * spmd_cpu_off_handler
114  ******************************************************************************/
spmd_cpu_off_handler(u_register_t unused)115 static int32_t spmd_cpu_off_handler(u_register_t unused)
116 {
117 	spmd_spm_core_context_t *ctx = spmd_get_context();
118 	unsigned int linear_id = plat_my_core_pos();
119 	int64_t rc;
120 
121 	assert(ctx != NULL);
122 	assert(ctx->state != SPMC_STATE_OFF);
123 
124 	/* Build an SPMD to SPMC direct message request. */
125 	spmd_build_spmc_message(get_gpregs_ctx(&ctx->cpu_ctx),
126 				FFA_FWK_MSG_PSCI, PSCI_CPU_OFF);
127 
128 	rc = spmd_spm_core_sync_entry(ctx);
129 	if (rc != 0ULL) {
130 		ERROR("%s failed (%" PRIu64 ") on CPU%u\n", __func__, rc, linear_id);
131 	}
132 
133 	/* Expect a direct message response from the SPMC. */
134 	u_register_t ffa_resp_func = read_ctx_reg(get_gpregs_ctx(&ctx->cpu_ctx),
135 						  CTX_GPREG_X0);
136 	if (ffa_resp_func != FFA_MSG_SEND_DIRECT_RESP_SMC32) {
137 		ERROR("%s invalid SPMC response (%lx).\n",
138 			__func__, ffa_resp_func);
139 		return -EINVAL;
140 	}
141 
142 	ctx->state = SPMC_STATE_OFF;
143 
144 	VERBOSE("CPU %u off!\n", linear_id);
145 
146 	return 0;
147 }
148 
149 /*******************************************************************************
150  * Structure populated by the SPM Dispatcher to perform any bookkeeping before
151  * PSCI executes a power mgmt. operation.
152  ******************************************************************************/
153 const spd_pm_ops_t spmd_pm = {
154 	.svc_on_finish = spmd_cpu_on_finish_handler,
155 	.svc_off = spmd_cpu_off_handler
156 };
157