xref: /openbmc/u-boot/arch/arm/lib/relocate_64.S (revision c0fb2fc0)
1/*
2 * relocate - common relocation function for AArch64 U-Boot
3 *
4 * (C) Copyright 2013
5 * Albert ARIBAUD <albert.u.boot@aribaud.net>
6 * David Feng <fenghua@phytium.com.cn>
7 *
8 * SPDX-License-Identifier:	GPL-2.0+
9 */
10
11#include <asm-offsets.h>
12#include <config.h>
13#include <elf.h>
14#include <linux/linkage.h>
15#include <asm/macro.h>
16
17/*
18 * void relocate_code (addr_moni)
19 *
20 * This function relocates the monitor code.
21 * x0 holds the destination address.
22 */
23ENTRY(relocate_code)
24	stp	x29, x30, [sp, #-32]!	/* create a stack frame */
25	mov	x29, sp
26	str	x0, [sp, #16]
27	/*
28	 * Copy u-boot from flash to RAM
29	 */
30	adr	x1, __image_copy_start	/* x1 <- Run &__image_copy_start */
31	subs	x9, x0, x1		/* x8 <- Run to copy offset */
32	b.eq	relocate_done		/* skip relocation */
33	/*
34	 * Don't ldr x1, __image_copy_start here, since if the code is already
35	 * running at an address other than it was linked to, that instruction
36	 * will load the relocated value of __image_copy_start. To
37	 * correctly apply relocations, we need to know the linked value.
38	 *
39	 * Linked &__image_copy_start, which we know was at
40	 * CONFIG_SYS_TEXT_BASE, which is stored in _TEXT_BASE, as a non-
41	 * relocated value, since it isn't a symbol reference.
42	 */
43	ldr	x1, _TEXT_BASE		/* x1 <- Linked &__image_copy_start */
44	subs	x9, x0, x1		/* x9 <- Link to copy offset */
45
46	adr	x1, __image_copy_start	/* x1 <- Run &__image_copy_start */
47	adr	x2, __image_copy_end	/* x2 <- Run &__image_copy_end */
48copy_loop:
49	ldp	x10, x11, [x1], #16	/* copy from source address [x1] */
50	stp	x10, x11, [x0], #16	/* copy to   target address [x0] */
51	cmp	x1, x2			/* until source end address [x2] */
52	b.lo	copy_loop
53	str	x0, [sp, #24]
54
55	/*
56	 * Fix .rela.dyn relocations
57	 */
58	adr	x2, __rel_dyn_start	/* x2 <- Run &__rel_dyn_start */
59	adr	x3, __rel_dyn_end	/* x3 <- Run &__rel_dyn_end */
60fixloop:
61	ldp	x0, x1, [x2], #16	/* (x0,x1) <- (SRC location, fixup) */
62	ldr	x4, [x2], #8		/* x4 <- addend */
63	and	x1, x1, #0xffffffff
64	cmp	x1, #R_AARCH64_RELATIVE
65	bne	fixnext
66
67	/* relative fix: store addend plus offset at dest location */
68	add	x0, x0, x9
69	add	x4, x4, x9
70	str	x4, [x0]
71fixnext:
72	cmp	x2, x3
73	b.lo	fixloop
74
75relocate_done:
76	switch_el x1, 3f, 2f, 1f
77	bl	hang
783:	mrs	x0, sctlr_el3
79	b	0f
802:	mrs	x0, sctlr_el2
81	b	0f
821:	mrs	x0, sctlr_el1
830:	tbz	w0, #2, 5f	/* skip flushing cache if disabled */
84	tbz	w0, #12, 4f	/* skip invalidating i-cache if disabled */
85	ic	iallu		/* i-cache invalidate all */
86	isb	sy
874:	ldp	x0, x1, [sp, #16]
88	bl	__asm_flush_dcache_range
895:	ldp	x29, x30, [sp],#32
90	ret
91ENDPROC(relocate_code)
92