xref: /openbmc/u-boot/arch/arm/cpu/armv8/start.S (revision 9fc2ed40)
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 <version.h>
11#include <linux/linkage.h>
12#include <asm/macro.h>
13#include <asm/armv8/mmu.h>
14
15/*************************************************************************
16 *
17 * Startup Code (reset vector)
18 *
19 *************************************************************************/
20
21.globl	_start
22_start:
23	b	reset
24
25	.align 3
26
27.globl	_TEXT_BASE
28_TEXT_BASE:
29	.quad	CONFIG_SYS_TEXT_BASE
30
31/*
32 * These are defined in the linker script.
33 */
34.globl	_end_ofs
35_end_ofs:
36	.quad	_end - _start
37
38.globl	_bss_start_ofs
39_bss_start_ofs:
40	.quad	__bss_start - _start
41
42.globl	_bss_end_ofs
43_bss_end_ofs:
44	.quad	__bss_end - _start
45
46reset:
47	/*
48	 * Could be EL3/EL2/EL1, Initial State:
49	 * Little Endian, MMU Disabled, i/dCache Disabled
50	 */
51	adr	x0, vectors
52	switch_el x1, 3f, 2f, 1f
533:	mrs	x0, scr_el3
54	orr	x0, x0, #0xf			/* SCR_EL3.NS|IRQ|FIQ|EA */
55	msr	scr_el3, x0
56	msr	vbar_el3, x0
57	msr	cptr_el3, xzr			/* Enable FP/SIMD */
58	ldr	x0, =COUNTER_FREQUENCY
59	msr	cntfrq_el0, x0			/* Initialize CNTFRQ */
60	b	0f
612:	msr	vbar_el2, x0
62	mov	x0, #0x33ff
63	msr	cptr_el2, x0			/* Enable FP/SIMD */
64	b	0f
651:	msr	vbar_el1, x0
66	mov	x0, #3 << 20
67	msr	cpacr_el1, x0			/* Enable FP/SIMD */
680:
69
70	/*
71	 * Cache/BPB/TLB Invalidate
72	 * i-cache is invalidated before enabled in icache_enable()
73	 * tlb is invalidated before mmu is enabled in dcache_enable()
74	 * d-cache is invalidated before enabled in dcache_enable()
75	 */
76
77	/* Processor specific initialization */
78	bl	lowlevel_init
79
80	branch_if_master x0, x1, master_cpu
81
82	/*
83	 * Slave CPUs
84	 */
85slave_cpu:
86	wfe
87	ldr	x1, =CPU_RELEASE_ADDR
88	ldr	x0, [x1]
89	cbz	x0, slave_cpu
90	br	x0			/* branch to the given address */
91
92	/*
93	 * Master CPU
94	 */
95master_cpu:
96	bl	_main
97
98/*-----------------------------------------------------------------------*/
99
100WEAK(lowlevel_init)
101	mov	x29, lr			/* Save LR */
102
103#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
104	branch_if_slave x0, 1f
105	ldr	x0, =GICD_BASE
106	bl	gic_init_secure
1071:
108#if defined(CONFIG_GICV3)
109	ldr	x0, =GICR_BASE
110	bl	gic_init_secure_percpu
111#elif defined(CONFIG_GICV2)
112	ldr	x0, =GICD_BASE
113	ldr	x1, =GICC_BASE
114	bl	gic_init_secure_percpu
115#endif
116#endif
117
118	branch_if_master x0, x1, 2f
119
120	/*
121	 * Slave should wait for master clearing spin table.
122	 * This sync prevent salves observing incorrect
123	 * value of spin table and jumping to wrong place.
124	 */
125#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
126#ifdef CONFIG_GICV2
127	ldr	x0, =GICC_BASE
128#endif
129	bl	gic_wait_for_interrupt
130#endif
131
132	/*
133	 * All slaves will enter EL2 and optionally EL1.
134	 */
135	bl	armv8_switch_to_el2
136#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
137	bl	armv8_switch_to_el1
138#endif
139
1402:
141	mov	lr, x29			/* Restore LR */
142	ret
143ENDPROC(lowlevel_init)
144
145WEAK(smp_kick_all_cpus)
146	/* Kick secondary cpus up by SGI 0 interrupt */
147	mov	x29, lr			/* Save LR */
148#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
149	ldr	x0, =GICD_BASE
150	bl	gic_kick_secondary_cpus
151#endif
152	mov	lr, x29			/* Restore LR */
153	ret
154ENDPROC(smp_kick_all_cpus)
155
156/*-----------------------------------------------------------------------*/
157
158ENTRY(c_runtime_cpu_setup)
159	/* Relocate vBAR */
160	adr	x0, vectors
161	switch_el x1, 3f, 2f, 1f
1623:	msr	vbar_el3, x0
163	b	0f
1642:	msr	vbar_el2, x0
165	b	0f
1661:	msr	vbar_el1, x0
1670:
168
169	ret
170ENDPROC(c_runtime_cpu_setup)
171