u-boot/arch/arm/lib/relocate_64.S
Ibai Erkiaga 98ffbb78e1 arm: arm64 32bit address relocation
Current relocation code is limited to 21bit PC-relative addressing
which might not be enough for bigger code sizes. The following patch
increases the addressing to 32bit PC-relative. This feature is
specially interesting if U-Boot is build without optimiation (-O0) as
the text section is increased significativelly.

Signed-off-by: Ibai Erkiaga <ibai.erkiaga-elorza@xilinx.com>
2019-04-22 18:13:24 -04:00

97 lines
2.9 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* relocate - common relocation function for AArch64 U-Boot
*
* (C) Copyright 2013
* Albert ARIBAUD <albert.u.boot@aribaud.net>
* David Feng <fenghua@phytium.com.cn>
*/
#include <asm-offsets.h>
#include <config.h>
#include <elf.h>
#include <linux/linkage.h>
#include <asm/macro.h>
/*
* void relocate_code (addr_moni)
*
* This function relocates the monitor code.
* x0 holds the destination address.
*/
ENTRY(relocate_code)
stp x29, x30, [sp, #-32]! /* create a stack frame */
mov x29, sp
str x0, [sp, #16]
/*
* Copy u-boot from flash to RAM
*/
adrp x1, __image_copy_start /* x1 <- address bits [31:12] */
add x1, x1, :lo12:__image_copy_start/* x1 <- address bits [11:00] */
subs x9, x0, x1 /* x9 <- Run to copy offset */
b.eq relocate_done /* skip relocation */
/*
* Don't ldr x1, __image_copy_start here, since if the code is already
* running at an address other than it was linked to, that instruction
* will load the relocated value of __image_copy_start. To
* correctly apply relocations, we need to know the linked value.
*
* Linked &__image_copy_start, which we know was at
* CONFIG_SYS_TEXT_BASE, which is stored in _TEXT_BASE, as a non-
* relocated value, since it isn't a symbol reference.
*/
ldr x1, _TEXT_BASE /* x1 <- Linked &__image_copy_start */
subs x9, x0, x1 /* x9 <- Link to copy offset */
adrp x1, __image_copy_start /* x1 <- address bits [31:12] */
add x1, x1, :lo12:__image_copy_start/* x1 <- address bits [11:00] */
adrp x2, __image_copy_end /* x2 <- address bits [31:12] */
add x2, x2, :lo12:__image_copy_end /* x2 <- address bits [11:00] */
copy_loop:
ldp x10, x11, [x1], #16 /* copy from source address [x1] */
stp x10, x11, [x0], #16 /* copy to target address [x0] */
cmp x1, x2 /* until source end address [x2] */
b.lo copy_loop
str x0, [sp, #24]
/*
* Fix .rela.dyn relocations
*/
adrp x2, __rel_dyn_start /* x2 <- address bits [31:12] */
add x2, x2, :lo12:__rel_dyn_start /* x2 <- address bits [11:00] */
adrp x3, __rel_dyn_end /* x3 <- address bits [31:12] */
add x3, x3, :lo12:__rel_dyn_end /* x3 <- address bits [11:00] */
fixloop:
ldp x0, x1, [x2], #16 /* (x0,x1) <- (SRC location, fixup) */
ldr x4, [x2], #8 /* x4 <- addend */
and x1, x1, #0xffffffff
cmp x1, #R_AARCH64_RELATIVE
bne fixnext
/* relative fix: store addend plus offset at dest location */
add x0, x0, x9
add x4, x4, x9
str x4, [x0]
fixnext:
cmp x2, x3
b.lo fixloop
relocate_done:
switch_el x1, 3f, 2f, 1f
bl hang
3: mrs x0, sctlr_el3
b 0f
2: mrs x0, sctlr_el2
b 0f
1: mrs x0, sctlr_el1
0: tbz w0, #2, 5f /* skip flushing cache if disabled */
tbz w0, #12, 4f /* skip invalidating i-cache if disabled */
ic iallu /* i-cache invalidate all */
isb sy
4: ldp x0, x1, [sp, #16]
bl __asm_flush_dcache_range
bl __asm_flush_l3_dcache
5: ldp x29, x30, [sp],#32
ret
ENDPROC(relocate_code)