xref: /openbmc/u-boot/arch/arm/cpu/armv8/start.S (revision 747778cf)
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#ifdef CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK
23/*
24 * Various SoCs need something special and SoC-specific up front in
25 * order to boot, allow them to set that in their boot0.h file and then
26 * use it here.
27 */
28#include <asm/arch/boot0.h>
29#else
30	b	reset
31#endif
32
33	.align 3
34
35.globl	_TEXT_BASE
36_TEXT_BASE:
37	.quad	CONFIG_SYS_TEXT_BASE
38
39/*
40 * These are defined in the linker script.
41 */
42.globl	_end_ofs
43_end_ofs:
44	.quad	_end - _start
45
46.globl	_bss_start_ofs
47_bss_start_ofs:
48	.quad	__bss_start - _start
49
50.globl	_bss_end_ofs
51_bss_end_ofs:
52	.quad	__bss_end - _start
53
54reset:
55	/* Allow the board to save important registers */
56	b	save_boot_params
57.globl	save_boot_params_ret
58save_boot_params_ret:
59
60#ifdef CONFIG_SYS_RESET_SCTRL
61	bl reset_sctrl
62#endif
63	/*
64	 * Could be EL3/EL2/EL1, Initial State:
65	 * Little Endian, MMU Disabled, i/dCache Disabled
66	 */
67	adr	x0, vectors
68	switch_el x1, 3f, 2f, 1f
693:	msr	vbar_el3, x0
70	mrs	x0, scr_el3
71	orr	x0, x0, #0xf			/* SCR_EL3.NS|IRQ|FIQ|EA */
72	msr	scr_el3, x0
73	msr	cptr_el3, xzr			/* Enable FP/SIMD */
74#ifdef COUNTER_FREQUENCY
75	ldr	x0, =COUNTER_FREQUENCY
76	msr	cntfrq_el0, x0			/* Initialize CNTFRQ */
77#endif
78	b	0f
792:	msr	vbar_el2, x0
80	mov	x0, #0x33ff
81	msr	cptr_el2, x0			/* Enable FP/SIMD */
82	b	0f
831:	msr	vbar_el1, x0
84	mov	x0, #3 << 20
85	msr	cpacr_el1, x0			/* Enable FP/SIMD */
860:
87
88	/*
89	 * Enable SMPEN bit for coherency.
90	 * This register is not architectural but at the moment
91	 * this bit should be set for A53/A57/A72.
92	 */
93#ifdef CONFIG_ARMV8_SET_SMPEN
94	mrs     x0, S3_1_c15_c2_1               /* cpuectlr_el1 */
95	orr     x0, x0, #0x40
96	msr     S3_1_c15_c2_1, x0
97#endif
98
99	/* Apply ARM core specific erratas */
100	bl	apply_core_errata
101
102	/*
103	 * Cache/BPB/TLB Invalidate
104	 * i-cache is invalidated before enabled in icache_enable()
105	 * tlb is invalidated before mmu is enabled in dcache_enable()
106	 * d-cache is invalidated before enabled in dcache_enable()
107	 */
108
109	/* Processor specific initialization */
110	bl	lowlevel_init
111
112#if defined(CONFIG_ARMV8_SPIN_TABLE) && !defined(CONFIG_SPL_BUILD)
113	branch_if_master x0, x1, master_cpu
114	b	spin_table_secondary_jump
115	/* never return */
116#elif defined(CONFIG_ARMV8_MULTIENTRY)
117	branch_if_master x0, x1, master_cpu
118
119	/*
120	 * Slave CPUs
121	 */
122slave_cpu:
123	wfe
124	ldr	x1, =CPU_RELEASE_ADDR
125	ldr	x0, [x1]
126	cbz	x0, slave_cpu
127	br	x0			/* branch to the given address */
128#endif /* CONFIG_ARMV8_MULTIENTRY */
129master_cpu:
130	bl	_main
131
132#ifdef CONFIG_SYS_RESET_SCTRL
133reset_sctrl:
134	switch_el x1, 3f, 2f, 1f
1353:
136	mrs	x0, sctlr_el3
137	b	0f
1382:
139	mrs	x0, sctlr_el2
140	b	0f
1411:
142	mrs	x0, sctlr_el1
143
1440:
145	ldr	x1, =0xfdfffffa
146	and	x0, x0, x1
147
148	switch_el x1, 6f, 5f, 4f
1496:
150	msr	sctlr_el3, x0
151	b	7f
1525:
153	msr	sctlr_el2, x0
154	b	7f
1554:
156	msr	sctlr_el1, x0
157
1587:
159	dsb	sy
160	isb
161	b	__asm_invalidate_tlb_all
162	ret
163#endif
164
165/*-----------------------------------------------------------------------*/
166
167WEAK(apply_core_errata)
168
169	mov	x29, lr			/* Save LR */
170	/* For now, we support Cortex-A57 specific errata only */
171
172	/* Check if we are running on a Cortex-A57 core */
173	branch_if_a57_core x0, apply_a57_core_errata
1740:
175	mov	lr, x29			/* Restore LR */
176	ret
177
178apply_a57_core_errata:
179
180#ifdef CONFIG_ARM_ERRATA_828024
181	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
182	/* Disable non-allocate hint of w-b-n-a memory type */
183	orr	x0, x0, #1 << 49
184	/* Disable write streaming no L1-allocate threshold */
185	orr	x0, x0, #3 << 25
186	/* Disable write streaming no-allocate threshold */
187	orr	x0, x0, #3 << 27
188	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
189#endif
190
191#ifdef CONFIG_ARM_ERRATA_826974
192	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
193	/* Disable speculative load execution ahead of a DMB */
194	orr	x0, x0, #1 << 59
195	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
196#endif
197
198#ifdef CONFIG_ARM_ERRATA_833471
199	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
200	/* FPSCR write flush.
201	 * Note that in some cases where a flush is unnecessary this
202	    could impact performance. */
203	orr	x0, x0, #1 << 38
204	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
205#endif
206
207#ifdef CONFIG_ARM_ERRATA_829520
208	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
209	/* Disable Indirect Predictor bit will prevent this erratum
210	    from occurring
211	 * Note that in some cases where a flush is unnecessary this
212	    could impact performance. */
213	orr	x0, x0, #1 << 4
214	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
215#endif
216
217#ifdef CONFIG_ARM_ERRATA_833069
218	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
219	/* Disable Enable Invalidates of BTB bit */
220	and	x0, x0, #0xE
221	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
222#endif
223	b 0b
224ENDPROC(apply_core_errata)
225
226/*-----------------------------------------------------------------------*/
227
228WEAK(lowlevel_init)
229	mov	x29, lr			/* Save LR */
230
231#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
232	branch_if_slave x0, 1f
233	ldr	x0, =GICD_BASE
234	bl	gic_init_secure
2351:
236#if defined(CONFIG_GICV3)
237	ldr	x0, =GICR_BASE
238	bl	gic_init_secure_percpu
239#elif defined(CONFIG_GICV2)
240	ldr	x0, =GICD_BASE
241	ldr	x1, =GICC_BASE
242	bl	gic_init_secure_percpu
243#endif
244#endif
245
246#ifdef CONFIG_ARMV8_MULTIENTRY
247	branch_if_master x0, x1, 2f
248
249	/*
250	 * Slave should wait for master clearing spin table.
251	 * This sync prevent salves observing incorrect
252	 * value of spin table and jumping to wrong place.
253	 */
254#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
255#ifdef CONFIG_GICV2
256	ldr	x0, =GICC_BASE
257#endif
258	bl	gic_wait_for_interrupt
259#endif
260
261	/*
262	 * All slaves will enter EL2 and optionally EL1.
263	 */
264	adr	x4, lowlevel_in_el2
265	ldr	x5, =ES_TO_AARCH64
266	bl	armv8_switch_to_el2
267
268lowlevel_in_el2:
269#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
270	adr	x4, lowlevel_in_el1
271	ldr	x5, =ES_TO_AARCH64
272	bl	armv8_switch_to_el1
273
274lowlevel_in_el1:
275#endif
276
277#endif /* CONFIG_ARMV8_MULTIENTRY */
278
2792:
280	mov	lr, x29			/* Restore LR */
281	ret
282ENDPROC(lowlevel_init)
283
284WEAK(smp_kick_all_cpus)
285	/* Kick secondary cpus up by SGI 0 interrupt */
286#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
287	ldr	x0, =GICD_BASE
288	b	gic_kick_secondary_cpus
289#endif
290	ret
291ENDPROC(smp_kick_all_cpus)
292
293/*-----------------------------------------------------------------------*/
294
295ENTRY(c_runtime_cpu_setup)
296	/* Relocate vBAR */
297	adr	x0, vectors
298	switch_el x1, 3f, 2f, 1f
2993:	msr	vbar_el3, x0
300	b	0f
3012:	msr	vbar_el2, x0
302	b	0f
3031:	msr	vbar_el1, x0
3040:
305
306	ret
307ENDPROC(c_runtime_cpu_setup)
308
309WEAK(save_boot_params)
310	b	save_boot_params_ret	/* back to my caller */
311ENDPROC(save_boot_params)
312