xref: /rk3399_ARM-atf/bl32/sp_min/aarch32/entrypoint.S (revision 0e14a7fbeb3014e719302c9b7f6a24c4030dfaf0)
1/*
2 * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7#include <arch.h>
8#include <asm_macros.S>
9#include <bl_common.h>
10#include <context.h>
11#include <el3_common_macros.S>
12#include <runtime_svc.h>
13#include <smcc_helpers.h>
14#include <smcc_macros.S>
15#include <xlat_tables_defs.h>
16
17	.globl	sp_min_vector_table
18	.globl	sp_min_entrypoint
19	.globl	sp_min_warm_entrypoint
20
21
22vector_base sp_min_vector_table
23	b	sp_min_entrypoint
24	b	plat_panic_handler	/* Undef */
25	b	handle_smc		/* Syscall */
26	b	plat_panic_handler	/* Prefetch abort */
27	b	plat_panic_handler	/* Data abort */
28	b	plat_panic_handler	/* Reserved */
29	b	plat_panic_handler	/* IRQ */
30	b	plat_panic_handler	/* FIQ */
31
32
33/*
34 * The Cold boot/Reset entrypoint for SP_MIN
35 */
36func sp_min_entrypoint
37#if !RESET_TO_SP_MIN
38	/* ---------------------------------------------------------------
39	 * Preceding bootloader has populated r0 with a pointer to a
40	 * 'bl_params_t' structure & r1 with a pointer to platform
41	 * specific structure
42	 * ---------------------------------------------------------------
43	 */
44	mov	r11, r0
45	mov	r12, r1
46
47	/* ---------------------------------------------------------------------
48	 * For !RESET_TO_SP_MIN systems, only the primary CPU ever reaches
49	 * sp_min_entrypoint() during the cold boot flow, so the cold/warm boot
50	 * and primary/secondary CPU logic should not be executed in this case.
51	 *
52	 * Also, assume that the previous bootloader has already set up the CPU
53	 * endianness and has initialised the memory.
54	 * ---------------------------------------------------------------------
55	 */
56	el3_entrypoint_common					\
57		_set_endian=0					\
58		_warm_boot_mailbox=0				\
59		_secondary_cold_boot=0				\
60		_init_memory=0					\
61		_init_c_runtime=1				\
62		_exception_vectors=sp_min_vector_table
63
64	/* ---------------------------------------------------------------------
65	 * Relay the previous bootloader's arguments to the platform layer
66	 * ---------------------------------------------------------------------
67	 */
68	mov	r0, r11
69	mov	r1, r12
70#else
71	/* ---------------------------------------------------------------------
72	 * For RESET_TO_SP_MIN systems which have a programmable reset address,
73	 * sp_min_entrypoint() is executed only on the cold boot path so we can
74	 * skip the warm boot mailbox mechanism.
75	 * ---------------------------------------------------------------------
76	 */
77	el3_entrypoint_common					\
78		_set_endian=1					\
79		_warm_boot_mailbox=!PROGRAMMABLE_RESET_ADDRESS	\
80		_secondary_cold_boot=!COLD_BOOT_SINGLE_CPU	\
81		_init_memory=1					\
82		_init_c_runtime=1				\
83		_exception_vectors=sp_min_vector_table
84
85	/* ---------------------------------------------------------------------
86	 * For RESET_TO_SP_MIN systems, BL32 (SP_MIN) is the first bootloader
87	 * to run so there's no argument to relay from a previous bootloader.
88	 * Zero the arguments passed to the platform layer to reflect that.
89	 * ---------------------------------------------------------------------
90	 */
91	mov	r0, #0
92	mov	r1, #0
93#endif /* RESET_TO_SP_MIN */
94
95	bl	sp_min_early_platform_setup
96	bl	sp_min_plat_arch_setup
97
98	/* Jump to the main function */
99	bl	sp_min_main
100
101	/* -------------------------------------------------------------
102	 * Clean the .data & .bss sections to main memory. This ensures
103	 * that any global data which was initialised by the primary CPU
104	 * is visible to secondary CPUs before they enable their data
105	 * caches and participate in coherency.
106	 * -------------------------------------------------------------
107	 */
108	ldr	r0, =__DATA_START__
109	ldr	r1, =__DATA_END__
110	sub	r1, r1, r0
111	bl	clean_dcache_range
112
113	ldr	r0, =__BSS_START__
114	ldr	r1, =__BSS_END__
115	sub	r1, r1, r0
116	bl	clean_dcache_range
117
118	/* Program the registers in cpu_context and exit monitor mode */
119	mov	r0, #NON_SECURE
120	bl	cm_get_context
121
122	/* Restore the SCR */
123	ldr	r2, [r0, #CTX_REGS_OFFSET + CTX_SCR]
124	stcopr	r2, SCR
125	isb
126
127	/* Restore the SCTLR  */
128	ldr	r2, [r0, #CTX_REGS_OFFSET + CTX_NS_SCTLR]
129	stcopr	r2, SCTLR
130
131	bl	smc_get_next_ctx
132	/* The other cpu_context registers have been copied to smc context */
133	b	sp_min_exit
134endfunc sp_min_entrypoint
135
136
137/*
138 * SMC handling function for SP_MIN.
139 */
140func handle_smc
141	smcc_save_gp_mode_regs
142
143	/* r0 points to smc_context */
144	mov	r2, r0				/* handle */
145	ldcopr	r0, SCR
146
147	/*
148	 * Save SCR in stack. r1 is pushed to meet the 8 byte
149	 * stack alignment requirement.
150	 */
151	push	{r0, r1}
152	and	r3, r0, #SCR_NS_BIT		/* flags */
153
154	/* Switch to Secure Mode*/
155	bic	r0, #SCR_NS_BIT
156	stcopr	r0, SCR
157	isb
158	ldr	r0, [r2, #SMC_CTX_GPREG_R0]	/* smc_fid */
159	/* Check whether an SMC64 is issued */
160	tst	r0, #(FUNCID_CC_MASK << FUNCID_CC_SHIFT)
161	beq	1f	/* SMC32 is detected */
162	mov	r0, #SMC_UNK
163	str	r0, [r2, #SMC_CTX_GPREG_R0]
164	mov	r0, r2
165	b	2f	/* Skip handling the SMC */
1661:
167	mov	r1, #0				/* cookie */
168	bl	handle_runtime_svc
1692:
170	/* r0 points to smc context */
171
172	/* Restore SCR from stack */
173	pop	{r1, r2}
174	stcopr	r1, SCR
175	isb
176
177	b	sp_min_exit
178endfunc handle_smc
179
180
181/*
182 * The Warm boot entrypoint for SP_MIN.
183 */
184func sp_min_warm_entrypoint
185	/*
186	 * On the warm boot path, most of the EL3 initialisations performed by
187	 * 'el3_entrypoint_common' must be skipped:
188	 *
189	 *  - Only when the platform bypasses the BL1/BL32 (SP_MIN) entrypoint by
190	 *    programming the reset address do we need to set the CPU endianness.
191	 *    In other cases, we assume this has been taken care by the
192	 *    entrypoint code.
193	 *
194	 *  - No need to determine the type of boot, we know it is a warm boot.
195	 *
196	 *  - Do not try to distinguish between primary and secondary CPUs, this
197	 *    notion only exists for a cold boot.
198	 *
199	 *  - No need to initialise the memory or the C runtime environment,
200	 *    it has been done once and for all on the cold boot path.
201	 */
202	el3_entrypoint_common					\
203		_set_endian=PROGRAMMABLE_RESET_ADDRESS		\
204		_warm_boot_mailbox=0				\
205		_secondary_cold_boot=0				\
206		_init_memory=0					\
207		_init_c_runtime=0				\
208		_exception_vectors=sp_min_vector_table
209
210	/*
211	 * We're about to enable MMU and participate in PSCI state coordination.
212	 *
213	 * The PSCI implementation invokes platform routines that enable CPUs to
214	 * participate in coherency. On a system where CPUs are not
215	 * cache-coherent without appropriate platform specific programming,
216	 * having caches enabled until such time might lead to coherency issues
217	 * (resulting from stale data getting speculatively fetched, among
218	 * others). Therefore we keep data caches disabled even after enabling
219	 * the MMU for such platforms.
220	 *
221	 * On systems with hardware-assisted coherency, or on single cluster
222	 * platforms, such platform specific programming is not required to
223	 * enter coherency (as CPUs already are); and there's no reason to have
224	 * caches disabled either.
225	 */
226	mov	r0, #DISABLE_DCACHE
227	bl	bl32_plat_enable_mmu
228
229#if HW_ASSISTED_COHERENCY || WARMBOOT_ENABLE_DCACHE_EARLY
230	ldcopr	r0, SCTLR
231	orr	r0, r0, #SCTLR_C_BIT
232	stcopr	r0, SCTLR
233	isb
234#endif
235
236	bl	sp_min_warm_boot
237
238	/* Program the registers in cpu_context and exit monitor mode */
239	mov	r0, #NON_SECURE
240	bl	cm_get_context
241
242	/* Restore the SCR */
243	ldr	r2, [r0, #CTX_REGS_OFFSET + CTX_SCR]
244	stcopr	r2, SCR
245	isb
246
247	/* Restore the SCTLR  */
248	ldr	r2, [r0, #CTX_REGS_OFFSET + CTX_NS_SCTLR]
249	stcopr	r2, SCTLR
250
251	bl	smc_get_next_ctx
252
253	/* The other cpu_context registers have been copied to smc context */
254	b	sp_min_exit
255endfunc sp_min_warm_entrypoint
256
257/*
258 * The function to restore the registers from SMC context and return
259 * to the mode restored to SPSR.
260 *
261 * Arguments : r0 must point to the SMC context to restore from.
262 */
263func sp_min_exit
264	smcc_restore_gp_mode_regs
265	eret
266endfunc sp_min_exit
267