1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
|
/*
* Copyright (c) 2013-2022, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <arch.h>
#include <asm_macros.S>
#include <bl1/bl1.h>
#include <common/bl_common.h>
#include <context.h>
/* -----------------------------------------------------------------------------
* Very simple stackless exception handlers used by BL1.
* -----------------------------------------------------------------------------
*/
.globl bl1_exceptions
vector_base bl1_exceptions
/* -----------------------------------------------------
* Current EL with SP0 : 0x0 - 0x200
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionSP0
mov x0, #SYNC_EXCEPTION_SP_EL0
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry SynchronousExceptionSP0
vector_entry IrqSP0
mov x0, #IRQ_SP_EL0
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry IrqSP0
vector_entry FiqSP0
mov x0, #FIQ_SP_EL0
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry FiqSP0
vector_entry SErrorSP0
mov x0, #SERROR_SP_EL0
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry SErrorSP0
/* -----------------------------------------------------
* Current EL with SPx: 0x200 - 0x400
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionSPx
mov x0, #SYNC_EXCEPTION_SP_ELX
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry SynchronousExceptionSPx
vector_entry IrqSPx
mov x0, #IRQ_SP_ELX
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry IrqSPx
vector_entry FiqSPx
mov x0, #FIQ_SP_ELX
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry FiqSPx
vector_entry SErrorSPx
mov x0, #SERROR_SP_ELX
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry SErrorSPx
/* -----------------------------------------------------
* Lower EL using AArch64 : 0x400 - 0x600
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionA64
/* Enable the SError interrupt */
msr daifclr, #DAIF_ABT_BIT
str x30, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]
/* Expect only SMC exceptions */
mrs x30, esr_el3
ubfx x30, x30, #ESR_EC_SHIFT, #ESR_EC_LENGTH
cmp x30, #EC_AARCH64_SMC
b.ne unexpected_sync_exception
b smc_handler64
end_vector_entry SynchronousExceptionA64
vector_entry IrqA64
mov x0, #IRQ_AARCH64
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry IrqA64
vector_entry FiqA64
mov x0, #FIQ_AARCH64
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry FiqA64
vector_entry SErrorA64
mov x0, #SERROR_AARCH64
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry SErrorA64
/* -----------------------------------------------------
* Lower EL using AArch32 : 0x600 - 0x800
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionA32
mov x0, #SYNC_EXCEPTION_AARCH32
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry SynchronousExceptionA32
vector_entry IrqA32
mov x0, #IRQ_AARCH32
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry IrqA32
vector_entry FiqA32
mov x0, #FIQ_AARCH32
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry FiqA32
vector_entry SErrorA32
mov x0, #SERROR_AARCH32
bl plat_report_exception
no_ret plat_panic_handler
end_vector_entry SErrorA32
func smc_handler64
/* ----------------------------------------------
* Detect if this is a RUN_IMAGE or other SMC.
* ----------------------------------------------
*/
mov x30, #BL1_SMC_RUN_IMAGE
cmp x30, x0
b.ne smc_handler
/* ------------------------------------------------
* Make sure only Secure world reaches here.
* ------------------------------------------------
*/
mrs x30, scr_el3
tst x30, #SCR_NS_BIT
b.ne unexpected_sync_exception
/* ----------------------------------------------
* Handling RUN_IMAGE SMC. First switch back to
* SP_EL0 for the C runtime stack.
* ----------------------------------------------
*/
ldr x30, [sp, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP]
msr spsel, #MODE_SP_EL0
mov sp, x30
/* ---------------------------------------------------------------------
* Pass EL3 control to next BL image.
* Here it expects X1 with the address of a entry_point_info_t
* structure describing the next BL image entrypoint.
* ---------------------------------------------------------------------
*/
mov x20, x1
mov x0, x20
bl bl1_print_next_bl_ep_info
ldp x0, x1, [x20, #ENTRY_POINT_INFO_PC_OFFSET]
msr elr_el3, x0
msr spsr_el3, x1
ubfx x0, x1, #MODE_EL_SHIFT, #2
cmp x0, #MODE_EL3
b.ne unexpected_sync_exception
bl disable_mmu_icache_el3
tlbi alle3
dsb ish /* ERET implies ISB, so it is not needed here */
#if SPIN_ON_BL1_EXIT
bl print_debug_loop_message
debug_loop:
b debug_loop
#endif
mov x0, x20
bl bl1_plat_prepare_exit
ldp x6, x7, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x30)]
ldp x4, x5, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x20)]
ldp x2, x3, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x10)]
ldp x0, x1, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x0)]
exception_return
endfunc smc_handler64
unexpected_sync_exception:
mov x0, #SYNC_EXCEPTION_AARCH64
bl plat_report_exception
no_ret plat_panic_handler
/* -----------------------------------------------------
* Save Secure/Normal world context and jump to
* BL1 SMC handler.
* -----------------------------------------------------
*/
smc_handler:
/* -----------------------------------------------------
* Save x0-x29 and ARMv8.3-PAuth (if enabled) registers.
* Save PMCR_EL0 and disable Cycle Counter.
* TODO: Revisit to store only SMCCC specified registers.
* -----------------------------------------------------
*/
bl prepare_el3_entry
#if ENABLE_PAUTH
/* -----------------------------------------------------
* Load and program stored APIAKey firmware key.
* Re-enable pointer authentication in EL3, as it was
* disabled before jumping to the next boot image.
* -----------------------------------------------------
*/
bl pauth_load_bl1_apiakey_enable
#endif
/* -----------------------------------------------------
* Populate the parameters for the SMC handler. We
* already have x0-x4 in place. x5 will point to a
* cookie (not used now). x6 will point to the context
* structure (SP_EL3) and x7 will contain flags we need
* to pass to the handler.
* -----------------------------------------------------
*/
mov x5, xzr
mov x6, sp
/* -----------------------------------------------------
* Restore the saved C runtime stack value which will
* become the new SP_EL0 i.e. EL3 runtime stack. It was
* saved in the 'cpu_context' structure prior to the last
* ERET from EL3.
* -----------------------------------------------------
*/
ldr x12, [x6, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP]
/* ---------------------------------------------
* Switch back to SP_EL0 for the C runtime stack.
* ---------------------------------------------
*/
msr spsel, #MODE_SP_EL0
mov sp, x12
/* -----------------------------------------------------
* Save the SPSR_EL3, ELR_EL3, & SCR_EL3 in case there
* is a world switch during SMC handling.
* -----------------------------------------------------
*/
mrs x16, spsr_el3
mrs x17, elr_el3
mrs x18, scr_el3
stp x16, x17, [x6, #CTX_EL3STATE_OFFSET + CTX_SPSR_EL3]
str x18, [x6, #CTX_EL3STATE_OFFSET + CTX_SCR_EL3]
/* Copy SCR_EL3.NS bit to the flag to indicate caller's security */
bfi x7, x18, #0, #1
/* -----------------------------------------------------
* Go to BL1 SMC handler.
* -----------------------------------------------------
*/
bl bl1_smc_handler
/* -----------------------------------------------------
* Do the transition to next BL image.
* -----------------------------------------------------
*/
b el3_exit
|