xref: /optee_os/core/arch/riscv/kernel/entry.S (revision 23f867d38149c501891c441213b4d9f5ee9ee94e)
1/* SPDX-License-Identifier: BSD-2-Clause */
2/*
3 * Copyright (c) 2023 Andes Technology Corporation
4 * Copyright 2022-2023 NXP
5 */
6
7#include <asm.S>
8#include <generated/asm-defines.h>
9#include <keep.h>
10#include <kernel/thread_private.h>
11#include <mm/core_mmu.h>
12#include <platform_config.h>
13#include <riscv.h>
14#include <riscv_macros.S>
15#include <tee/optee_abi.h>
16#include <tee/teeabi_opteed.h>
17#include <tee/teeabi_opteed_macros.h>
18
19.section .data
20.balign 4
21
22#ifdef CFG_BOOT_SYNC_CPU
23.equ SEM_CPU_READY, 1
24#endif
25
26	/*
27	 * Setup sp to point to the top of the tmp stack for the current CPU:
28	 * sp is assigned:
29	 * stack_tmp + (hartid + 1) * stack_tmp_stride - STACK_TMP_GUARD
30	 */
31.macro set_sp
32	/* Unsupported CPU, park it before it breaks something */
33	li	t1, CFG_TEE_CORE_NB_CORE
34	csrr	t0, CSR_XSCRATCH
35	bge	t0, t1, unhandled_cpu
36	addi	t0, t0, 1
37	lw	t1, stack_tmp_stride
38	/*
39	 * t0 = (hartid + 1)
40	 * t1 = value of stack_tmp_stride
41	 * value of stack_tmp_rel = stack_tmp - stack_tmp_rel - STACK_TMP_GUARD
42	 * sp = stack_tmp + (hartid + 1) * stack_tmp_stride - STACK_TMP_GUARD
43	 *    = stack_tmp_rel + (value of stack_tmp_rel) + (t0 * t1)
44	 */
45	mul	t1, t0, t1
46	la	t2, stack_tmp_rel
47	lw	t0, 0(t2)
48	add	t0, t0, t2
49	add	sp, t1, t0
50.endm
51
52.macro cpu_is_ready
53#ifdef CFG_BOOT_SYNC_CPU
54	csrr	t0, CSR_XSCRATCH
55	la	t1, sem_cpu_sync
56	slli	t0, t0, 2
57	add	t1, t1, t0
58	li	t2, SEM_CPU_READY
59	sw	t2, 0(t1)
60	fence
61#endif
62.endm
63
64.macro set_tp
65	csrr	a0, CSR_XSCRATCH
66	li	a1, THREAD_CORE_LOCAL_SIZE
67	la	tp, thread_core_local
68	mul	a2, a1, a0
69	add	tp, tp, a2
70	sw	a0, THREAD_CORE_LOCAL_HART_ID(tp)
71.endm
72
73.macro set_satp
74	la	a1, boot_mmu_config
75	LDR	a0, CORE_MMU_CONFIG_SATP(a1)
76	csrw	CSR_SATP, a0
77	sfence.vma	zero, zero
78.endm
79
80.macro wait_primary
81#ifdef CFG_BOOT_SYNC_CPU
82	la	t0, sem_cpu_sync
83	li	t2, SEM_CPU_READY
841:
85	fence	w, w
86	lw	t1, 0(t0)
87	bne	t1, t2, 1b
88#endif
89.endm
90
91.macro wait_secondary
92#ifdef CFG_BOOT_SYNC_CPU
93	la	t0, sem_cpu_sync
94	li	t1, CFG_TEE_CORE_NB_CORE
95	li	t2, SEM_CPU_READY
961:
97	addi	t1, t1, -1
98	beqz	t1, 3f
99	addi	t0, t0, 4
1002:
101	fence
102	lw	t1, 0(t0)
103	bne	t1, t2, 2b
104	j	1b
1053:
106#endif
107.endm
108
109#ifdef CFG_BOOT_SYNC_CPU
110#define flush_cpu_semaphores \
111		la	t0, sem_cpu_sync_start
112		la	t1, sem_cpu_sync_end
113		fence
114#else
115#define flush_cpu_semaphores
116#endif
117
118.macro bootargs_entry
119	/*
120	 * Save boot arguments
121	 */
122	la	t0, boot_args
123	/* Save boot hart */
124	STR	a0, REGOFF(0)(t0)
125	/* Save FDT address */
126	STR	a1, REGOFF(1)(t0)
127.endm
128
129FUNC _start , :
130	/*
131	 * Register usage:
132	 * a0	- if non-NULL holds the hart ID
133	 * a1	- if non-NULL holds the system DTB address
134	 *
135	 * CSR_XSCRATCH - saved a0
136	 * s1 - saved a1
137	 */
138.option push
139.option norelax
140	la	gp, __global_pointer$
141.option pop
142#ifdef CFG_RISCV_M_MODE
143	csrr	a0, CSR_MHARTID
144#endif
145	csrw	CSR_XSCRATCH, a0
146#if defined(CFG_DT_ADDR)
147	li	s1, CFG_DT_ADDR
148#else
149	mv	s1, a1		/* Save device tree address into s1 */
150#endif
151
152	/* Only first hart who wins lottery runs the primary boot sequence. */
153	la	a3, hart_lottery
154	li	a2, 1
155	amoadd.w a3, a2, (a3)
156	bnez	a3, reset_secondary
157	jal	reset_primary
158	j	.
159END_FUNC _start
160
161LOCAL_FUNC reset_primary , : , .identity_map
162UNWIND(	.cantunwind)
163
164	bootargs_entry
165
166	/*
167	 * Zero bss
168	 */
169	lla	t0, __bss_start
170	lla	t1, __bss_end
171	beq	t0, t1, 1f
1720:
173	STR	zero, (t0)
174	add	t0, t0, RISCV_XLEN_BYTES
175	bne	t0, t1, 0b
1761:
177#ifdef CFG_RISCV_S_MODE
178	lla	t0, _start
179	lla	t1, start_addr
180	STR	t0, (t1)
181#endif
182
183	csrw	CSR_SATP, zero
184	set_sp
185	set_tp
186
187	jal	thread_init_thread_core_local
188	jal	plat_primary_init_early
189	jal	console_init
190
191	mv	a0, x0
192	la	a1, boot_mmu_config
193	jal	core_init_mmu_map
194
195	set_satp
196
197	jal	boot_init_primary_early
198
199	/*
200	 * Before entering boot_init_primary_late(), we do these two steps:
201	 * 1. Save current sp to s2, and set sp as threads[0].stack_va_end
202	 * 2. Clear the flag which indicates usage of the temporary stack in the
203	 *    current hart's thread_core_local structure.
204	 */
205	mv	s2, sp
206	la	a0, threads
207	LDR	a0, THREAD_CTX_STACK_VA_END(a0)
208	mv	sp, a0
209	jal	thread_get_core_local
210	mv	s3, a0
211	STR	x0, THREAD_CORE_LOCAL_FLAGS(s3)
212
213	mv	a0, s1		/* s1 contains saved device tree address */
214	mv	a1, x0		/* unused */
215	jal	boot_init_primary_late
216
217	/*
218	 * After returning from boot_init_primary_late(), the flag and sp are
219	 * restored.
220	 */
221	li	a0, THREAD_CLF_TMP
222	STR	a0, THREAD_CORE_LOCAL_FLAGS(s3)
223	mv	sp, s2
224
225	cpu_is_ready
226	flush_cpu_semaphores
227	wait_secondary
228
229	jal	thread_clr_boot_thread
230
231	li	a0, TEEABI_OPTEED_RETURN_ENTRY_DONE
232	la	a1, thread_vector_table
233	j	thread_return_to_udomain
234END_FUNC reset_primary
235
236LOCAL_FUNC reset_secondary , : , .identity_map
237UNWIND(	.cantunwind)
238	wait_primary
239	csrw	CSR_SATP, zero
240	set_sp
241	set_tp
242	set_satp
243	cpu_is_ready
244
245	jal	boot_init_secondary
246#ifdef CFG_RISCV_WITH_M_MODE_SM
247	/* Return to untrusted domain */
248	li	a0, TEEABI_OPTEED_RETURN_ON_DONE
249	j	thread_return_to_udomain
250#endif
251	j	.
252END_FUNC reset_secondary
253
254LOCAL_FUNC unhandled_cpu , :
255	wfi
256	j	unhandled_cpu
257END_FUNC unhandled_cpu
258
259	.section .identity_map.data
260	.balign	8
261LOCAL_DATA hart_lottery , :
262	/* The hart who first increments this variable will be primary hart. */
263	.word	0
264END_DATA hart_lottery
265
266#ifdef CFG_BOOT_SYNC_CPU
267LOCAL_DATA sem_cpu_sync_start , :
268	.word	sem_cpu_sync
269END_DATA sem_cpu_sync_start
270
271LOCAL_DATA sem_cpu_sync_end , :
272	.word	sem_cpu_sync + (CFG_TEE_CORE_NB_CORE << 2)
273END_DATA sem_cpu_sync_end
274#endif
275
276LOCAL_DATA stack_tmp_rel , :
277	.word	stack_tmp - stack_tmp_rel - STACK_TMP_GUARD
278END_DATA stack_tmp_rel
279
280LOCAL_DATA stack_tmp_stride_rel , :
281	.word	stack_tmp_stride - stack_tmp_stride_rel
282END_DATA stack_tmp_stride_rel
283
284	.balign	8
285LOCAL_DATA boot_mmu_config , : /* struct core_mmu_config */
286	.skip	CORE_MMU_CONFIG_SIZE
287END_DATA boot_mmu_config
288