xref: /rk3399_ARM-atf/bl1/aarch64/bl1_context_mgmt.c (revision 51faada71a219a8b94cd8d8e423f0f22e9da4d8f)
1 /*
2  * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  * Redistributions of source code must retain the above copyright notice, this
8  * list of conditions and the following disclaimer.
9  *
10  * Redistributions in binary form must reproduce the above copyright notice,
11  * this list of conditions and the following disclaimer in the documentation
12  * and/or other materials provided with the distribution.
13  *
14  * Neither the name of ARM nor the names of its contributors may be used
15  * to endorse or promote products derived from this software without specific
16  * prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <arch_helpers.h>
32 #include <assert.h>
33 #include <context.h>
34 #include <context_mgmt.h>
35 #include <debug.h>
36 #include <platform.h>
37 
38 /*
39  * Following array will be used for context management.
40  * There are 2 instances, for the Secure and Non-Secure contexts.
41  */
42 static cpu_context_t bl1_cpu_context[2];
43 
44 /* Following contains the cpu context pointers. */
45 static void *bl1_cpu_context_ptr[2];
46 
47 
48 void *cm_get_context(uint32_t security_state)
49 {
50 	assert(sec_state_is_valid(security_state));
51 	return bl1_cpu_context_ptr[security_state];
52 }
53 
54 void cm_set_context(void *context, uint32_t security_state)
55 {
56 	assert(sec_state_is_valid(security_state));
57 	bl1_cpu_context_ptr[security_state] = context;
58 }
59 
60 /*******************************************************************************
61  * This function prepares the context for Secure/Normal world images.
62  * Normal world images are transitioned to EL2(if supported) else EL1.
63  ******************************************************************************/
64 void bl1_prepare_next_image(unsigned int image_id)
65 {
66 	unsigned int security_state;
67 	image_desc_t *image_desc;
68 	entry_point_info_t *next_bl_ep;
69 
70 #if CTX_INCLUDE_AARCH32_REGS
71 	/*
72 	 * Ensure that the build flag to save AArch32 system registers in CPU
73 	 * context is not set for AArch64-only platforms.
74 	 */
75 	if (((read_id_aa64pfr0_el1() >> ID_AA64PFR0_EL1_SHIFT)
76 			& ID_AA64PFR0_ELX_MASK) == 0x1) {
77 		ERROR("EL1 supports AArch64-only. Please set build flag "
78 				"CTX_INCLUDE_AARCH32_REGS = 0");
79 		panic();
80 	}
81 #endif
82 
83 	/* Get the image descriptor. */
84 	image_desc = bl1_plat_get_image_desc(image_id);
85 	assert(image_desc);
86 
87 	/* Get the entry point info. */
88 	next_bl_ep = &image_desc->ep_info;
89 
90 	/* Get the image security state. */
91 	security_state = GET_SECURITY_STATE(next_bl_ep->h.attr);
92 
93 	/* Setup the Secure/Non-Secure context if not done already. */
94 	if (!cm_get_context(security_state))
95 		cm_set_context(&bl1_cpu_context[security_state], security_state);
96 
97 	/* Prepare the SPSR for the next BL image. */
98 	if (security_state == SECURE) {
99 		next_bl_ep->spsr = SPSR_64(MODE_EL1, MODE_SP_ELX,
100 				   DISABLE_ALL_EXCEPTIONS);
101 	} else {
102 		/* Use EL2 if supported else use EL1. */
103 		if (read_id_aa64pfr0_el1() &
104 			(ID_AA64PFR0_ELX_MASK << ID_AA64PFR0_EL2_SHIFT)) {
105 			next_bl_ep->spsr = SPSR_64(MODE_EL2, MODE_SP_ELX,
106 				DISABLE_ALL_EXCEPTIONS);
107 		} else {
108 			next_bl_ep->spsr = SPSR_64(MODE_EL1, MODE_SP_ELX,
109 			   DISABLE_ALL_EXCEPTIONS);
110 		}
111 	}
112 
113 	/* Allow platform to make change */
114 	bl1_plat_set_ep_info(image_id, next_bl_ep);
115 
116 	/* Prepare the context for the next BL image. */
117 	cm_init_my_context(next_bl_ep);
118 	cm_prepare_el3_exit(security_state);
119 
120 	/* Indicate that image is in execution state. */
121 	image_desc->state = IMAGE_STATE_EXECUTED;
122 
123 	print_entry_point_info(next_bl_ep);
124 }
125