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.h>
8#include <arch_helpers.h>
9#include <assert.h>
10#include <bl31.h>
11#include <bl_common.h>
12#include <console.h>
13#include <context_mgmt.h>
14#include <debug.h>
15#include <platform.h>
16#include <pmf.h>
17#include <runtime_instr.h>
18#include <runtime_svc.h>
19#include <string.h>
20
21#if ENABLE_RUNTIME_INSTRUMENTATION
22PMF_REGISTER_SERVICE_SMC(rt_instr_svc, PMF_RT_INSTR_SVC_ID,
23	RT_INSTR_TOTAL_IDS, PMF_STORE_ENABLE)
24#endif
25
26/*******************************************************************************
27 * This function pointer is used to initialise the BL32 image. It's initialized
28 * by SPD calling bl31_register_bl32_init after setting up all things necessary
29 * for SP execution. In cases where both SPD and SP are absent, or when SPD
30 * finds it impossible to execute SP, this pointer is left as NULL
31 ******************************************************************************/
32static int32_t (*bl32_init)(void);
33
34/*******************************************************************************
35 * Variable to indicate whether next image to execute after BL31 is BL33
36 * (non-secure & default) or BL32 (secure).
37 ******************************************************************************/
38static uint32_t next_image_type = NON_SECURE;
39
40/*
41 * Implement the ARM Standard Service function to get arguments for a
42 * particular service.
43 */
44uintptr_t get_arm_std_svc_args(unsigned int svc_mask)
45{
46	/* Setup the arguments for PSCI Library */
47	DEFINE_STATIC_PSCI_LIB_ARGS_V1(psci_args, bl31_warm_entrypoint);
48
49	/* PSCI is the only ARM Standard Service implemented */
50	assert(svc_mask == PSCI_FID_MASK);
51
52	return (uintptr_t)&psci_args;
53}
54
55/*******************************************************************************
56 * Simple function to initialise all BL31 helper libraries.
57 ******************************************************************************/
58void bl31_lib_init(void)
59{
60	cm_init();
61}
62
63/*******************************************************************************
64 * BL31 is responsible for setting up the runtime services for the primary cpu
65 * before passing control to the bootloader or an Operating System. This
66 * function calls runtime_svc_init() which initializes all registered runtime
67 * services. The run time services would setup enough context for the core to
68 * swtich to the next exception level. When this function returns, the core will
69 * switch to the programmed exception level via. an ERET.
70 ******************************************************************************/
71void bl31_main(void)
72{
73	NOTICE("BL31: %s\n", version_string);
74	NOTICE("BL31: %s\n", build_message);
75
76	/* Perform platform setup in BL31 */
77	bl31_platform_setup();
78
79	/* Initialise helper libraries */
80	bl31_lib_init();
81
82	/* Initialize the runtime services e.g. psci. */
83	INFO("BL31: Initializing runtime services\n");
84	runtime_svc_init();
85
86	/*
87	 * All the cold boot actions on the primary cpu are done. We now need to
88	 * decide which is the next image (BL32 or BL33) and how to execute it.
89	 * If the SPD runtime service is present, it would want to pass control
90	 * to BL32 first in S-EL1. In that case, SPD would have registered a
91	 * function to intialize bl32 where it takes responsibility of entering
92	 * S-EL1 and returning control back to bl31_main. Once this is done we
93	 * can prepare entry into BL33 as normal.
94	 */
95
96	/*
97	 * If SPD had registerd an init hook, invoke it.
98	 */
99	if (bl32_init) {
100		INFO("BL31: Initializing BL32\n");
101		(*bl32_init)();
102	}
103	/*
104	 * We are ready to enter the next EL. Prepare entry into the image
105	 * corresponding to the desired security state after the next ERET.
106	 */
107	bl31_prepare_next_image_entry();
108
109	console_flush();
110
111	/*
112	 * Perform any platform specific runtime setup prior to cold boot exit
113	 * from BL31
114	 */
115	bl31_plat_runtime_setup();
116}
117
118/*******************************************************************************
119 * Accessor functions to help runtime services decide which image should be
120 * executed after BL31. This is BL33 or the non-secure bootloader image by
121 * default but the Secure payload dispatcher could override this by requesting
122 * an entry into BL32 (Secure payload) first. If it does so then it should use
123 * the same API to program an entry into BL33 once BL32 initialisation is
124 * complete.
125 ******************************************************************************/
126void bl31_set_next_image_type(uint32_t security_state)
127{
128	assert(sec_state_is_valid(security_state));
129	next_image_type = security_state;
130}
131
132uint32_t bl31_get_next_image_type(void)
133{
134	return next_image_type;
135}
136
137/*******************************************************************************
138 * This function programs EL3 registers and performs other setup to enable entry
139 * into the next image after BL31 at the next ERET.
140 ******************************************************************************/
141void bl31_prepare_next_image_entry(void)
142{
143	entry_point_info_t *next_image_info;
144	uint32_t image_type;
145
146#if CTX_INCLUDE_AARCH32_REGS
147	/*
148	 * Ensure that the build flag to save AArch32 system registers in CPU
149	 * context is not set for AArch64-only platforms.
150	 */
151	if (EL_IMPLEMENTED(1) == EL_IMPL_A64ONLY) {
152		ERROR("EL1 supports AArch64-only. Please set build flag "
153				"CTX_INCLUDE_AARCH32_REGS = 0");
154		panic();
155	}
156#endif
157
158	/* Determine which image to execute next */
159	image_type = bl31_get_next_image_type();
160
161	/* Program EL3 registers to enable entry into the next EL */
162	next_image_info = bl31_plat_get_next_image_ep_info(image_type);
163	assert(next_image_info);
164	assert(image_type == GET_SECURITY_STATE(next_image_info->h.attr));
165
166	INFO("BL31: Preparing for EL3 exit to %s world\n",
167		(image_type == SECURE) ? "secure" : "normal");
168	print_entry_point_info(next_image_info);
169	cm_init_my_context(next_image_info);
170	cm_prepare_el3_exit(image_type);
171}
172
173/*******************************************************************************
174 * This function initializes the pointer to BL32 init function. This is expected
175 * to be called by the SPD after it finishes all its initialization
176 ******************************************************************************/
177void bl31_register_bl32_init(int32_t (*func)(void))
178{
179	bl32_init = func;
180}
181