xref: /openbmc/u-boot/arch/arm/cpu/armv8/start.S (revision 5044c9cc)
1/*
2 * (C) Copyright 2013
3 * David Feng <fenghua@phytium.com.cn>
4 *
5 * SPDX-License-Identifier:	GPL-2.0+
6 */
7
8#include <asm-offsets.h>
9#include <config.h>
10#include <linux/linkage.h>
11#include <asm/macro.h>
12#include <asm/armv8/mmu.h>
13
14/*************************************************************************
15 *
16 * Startup Code (reset vector)
17 *
18 *************************************************************************/
19
20.globl	_start
21_start:
22	b	reset
23
24	.align 3
25
26.globl	_TEXT_BASE
27_TEXT_BASE:
28	.quad	CONFIG_SYS_TEXT_BASE
29
30/*
31 * These are defined in the linker script.
32 */
33.globl	_end_ofs
34_end_ofs:
35	.quad	_end - _start
36
37.globl	_bss_start_ofs
38_bss_start_ofs:
39	.quad	__bss_start - _start
40
41.globl	_bss_end_ofs
42_bss_end_ofs:
43	.quad	__bss_end - _start
44
45reset:
46#ifdef CONFIG_SYS_RESET_SCTRL
47	bl reset_sctrl
48#endif
49	/*
50	 * Could be EL3/EL2/EL1, Initial State:
51	 * Little Endian, MMU Disabled, i/dCache Disabled
52	 */
53	adr	x0, vectors
54	switch_el x1, 3f, 2f, 1f
553:	msr	vbar_el3, x0
56	mrs	x0, scr_el3
57	orr	x0, x0, #0xf			/* SCR_EL3.NS|IRQ|FIQ|EA */
58	msr	scr_el3, x0
59	msr	cptr_el3, xzr			/* Enable FP/SIMD */
60#ifdef COUNTER_FREQUENCY
61	ldr	x0, =COUNTER_FREQUENCY
62	msr	cntfrq_el0, x0			/* Initialize CNTFRQ */
63#endif
64	b	0f
652:	msr	vbar_el2, x0
66	mov	x0, #0x33ff
67	msr	cptr_el2, x0			/* Enable FP/SIMD */
68	b	0f
691:	msr	vbar_el1, x0
70	mov	x0, #3 << 20
71	msr	cpacr_el1, x0			/* Enable FP/SIMD */
720:
73
74	/* Apply ARM core specific erratas */
75	bl	apply_core_errata
76
77	/*
78	 * Cache/BPB/TLB Invalidate
79	 * i-cache is invalidated before enabled in icache_enable()
80	 * tlb is invalidated before mmu is enabled in dcache_enable()
81	 * d-cache is invalidated before enabled in dcache_enable()
82	 */
83
84	/* Processor specific initialization */
85	bl	lowlevel_init
86
87#ifdef CONFIG_ARMV8_MULTIENTRY
88	branch_if_master x0, x1, master_cpu
89
90	/*
91	 * Slave CPUs
92	 */
93slave_cpu:
94	wfe
95	ldr	x1, =CPU_RELEASE_ADDR
96	ldr	x0, [x1]
97	cbz	x0, slave_cpu
98	br	x0			/* branch to the given address */
99master_cpu:
100	/* On the master CPU */
101#endif /* CONFIG_ARMV8_MULTIENTRY */
102
103	bl	_main
104
105#ifdef CONFIG_SYS_RESET_SCTRL
106reset_sctrl:
107	switch_el x1, 3f, 2f, 1f
1083:
109	mrs	x0, sctlr_el3
110	b	0f
1112:
112	mrs	x0, sctlr_el2
113	b	0f
1141:
115	mrs	x0, sctlr_el1
116
1170:
118	ldr	x1, =0xfdfffffa
119	and	x0, x0, x1
120
121	switch_el x1, 6f, 5f, 4f
1226:
123	msr	sctlr_el3, x0
124	b	7f
1255:
126	msr	sctlr_el2, x0
127	b	7f
1284:
129	msr	sctlr_el1, x0
130
1317:
132	dsb	sy
133	isb
134	b	__asm_invalidate_tlb_all
135	ret
136#endif
137
138/*-----------------------------------------------------------------------*/
139
140WEAK(apply_core_errata)
141
142	mov	x29, lr			/* Save LR */
143	/* For now, we support Cortex-A57 specific errata only */
144
145	/* Check if we are running on a Cortex-A57 core */
146	branch_if_a57_core x0, apply_a57_core_errata
1470:
148	mov	lr, x29			/* Restore LR */
149	ret
150
151apply_a57_core_errata:
152
153#ifdef CONFIG_ARM_ERRATA_828024
154	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
155	/* Disable non-allocate hint of w-b-n-a memory type */
156	orr	x0, x0, #1 << 49
157	/* Disable write streaming no L1-allocate threshold */
158	orr	x0, x0, #3 << 25
159	/* Disable write streaming no-allocate threshold */
160	orr	x0, x0, #3 << 27
161	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
162#endif
163
164#ifdef CONFIG_ARM_ERRATA_826974
165	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
166	/* Disable speculative load execution ahead of a DMB */
167	orr	x0, x0, #1 << 59
168	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
169#endif
170
171#ifdef CONFIG_ARM_ERRATA_833471
172	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
173	/* FPSCR write flush.
174	 * Note that in some cases where a flush is unnecessary this
175	    could impact performance. */
176	orr	x0, x0, #1 << 38
177	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
178#endif
179
180#ifdef CONFIG_ARM_ERRATA_829520
181	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
182	/* Disable Indirect Predictor bit will prevent this erratum
183	    from occurring
184	 * Note that in some cases where a flush is unnecessary this
185	    could impact performance. */
186	orr	x0, x0, #1 << 4
187	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
188#endif
189
190#ifdef CONFIG_ARM_ERRATA_833069
191	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
192	/* Disable Enable Invalidates of BTB bit */
193	and	x0, x0, #0xE
194	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
195#endif
196	b 0b
197ENDPROC(apply_core_errata)
198
199/*-----------------------------------------------------------------------*/
200
201WEAK(lowlevel_init)
202	mov	x29, lr			/* Save LR */
203
204#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
205	branch_if_slave x0, 1f
206	ldr	x0, =GICD_BASE
207	bl	gic_init_secure
2081:
209#if defined(CONFIG_GICV3)
210	ldr	x0, =GICR_BASE
211	bl	gic_init_secure_percpu
212#elif defined(CONFIG_GICV2)
213	ldr	x0, =GICD_BASE
214	ldr	x1, =GICC_BASE
215	bl	gic_init_secure_percpu
216#endif
217#endif
218
219#ifndef CONFIG_ARMV8_MULTIENTRY
220	branch_if_master x0, x1, 2f
221
222	/*
223	 * Slave should wait for master clearing spin table.
224	 * This sync prevent salves observing incorrect
225	 * value of spin table and jumping to wrong place.
226	 */
227#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
228#ifdef CONFIG_GICV2
229	ldr	x0, =GICC_BASE
230#endif
231	bl	gic_wait_for_interrupt
232#endif
233
234	/*
235	 * All slaves will enter EL2 and optionally EL1.
236	 */
237	bl	armv8_switch_to_el2
238#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
239	bl	armv8_switch_to_el1
240#endif
241
242#endif /* CONFIG_ARMV8_MULTIENTRY */
243
2442:
245	mov	lr, x29			/* Restore LR */
246	ret
247ENDPROC(lowlevel_init)
248
249WEAK(smp_kick_all_cpus)
250	/* Kick secondary cpus up by SGI 0 interrupt */
251	mov	x29, lr			/* Save LR */
252#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
253	ldr	x0, =GICD_BASE
254	bl	gic_kick_secondary_cpus
255#endif
256	mov	lr, x29			/* Restore LR */
257	ret
258ENDPROC(smp_kick_all_cpus)
259
260/*-----------------------------------------------------------------------*/
261
262ENTRY(c_runtime_cpu_setup)
263	/* Relocate vBAR */
264	adr	x0, vectors
265	switch_el x1, 3f, 2f, 1f
2663:	msr	vbar_el3, x0
267	b	0f
2682:	msr	vbar_el2, x0
269	b	0f
2701:	msr	vbar_el1, x0
2710:
272
273	ret
274ENDPROC(c_runtime_cpu_setup)
275