1/* 2 * relocate - common relocation function for ARM U-Boot 3 * 4 * Copyright (c) 2013 Albert ARIBAUD <albert.u.boot@aribaud.net> 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9#include <asm-offsets.h> 10#include <config.h> 11#include <elf.h> 12#include <linux/linkage.h> 13#ifdef CONFIG_CPU_V7M 14#include <asm/armv7m.h> 15#endif 16 17/* 18 * Default/weak exception vectors relocation routine 19 * 20 * This routine covers the standard ARM cases: normal (0x00000000), 21 * high (0xffff0000) and VBAR. SoCs which do not comply with any of 22 * the standard cases must provide their own, strong, version. 23 */ 24 25 .section .text.relocate_vectors,"ax",%progbits 26 .weak relocate_vectors 27 28ENTRY(relocate_vectors) 29 30#ifdef CONFIG_CPU_V7M 31 /* 32 * On ARMv7-M we only have to write the new vector address 33 * to VTOR register. 34 */ 35 ldr r0, [r9, #GD_RELOCADDR] /* r0 = gd->relocaddr */ 36 ldr r1, =V7M_SCB_BASE 37 str r0, [r1, V7M_SCB_VTOR] 38#else 39#ifdef CONFIG_HAS_VBAR 40 /* 41 * If the ARM processor has the security extensions, 42 * use VBAR to relocate the exception vectors. 43 */ 44 ldr r0, [r9, #GD_RELOCADDR] /* r0 = gd->relocaddr */ 45 mcr p15, 0, r0, c12, c0, 0 /* Set VBAR */ 46#else 47 /* 48 * Copy the relocated exception vectors to the 49 * correct address 50 * CP15 c1 V bit gives us the location of the vectors: 51 * 0x00000000 or 0xFFFF0000. 52 */ 53 ldr r0, [r9, #GD_RELOCADDR] /* r0 = gd->relocaddr */ 54 mrc p15, 0, r2, c1, c0, 0 /* V bit (bit[13]) in CP15 c1 */ 55 ands r2, r2, #(1 << 13) 56 ldreq r1, =0x00000000 /* If V=0 */ 57 ldrne r1, =0xFFFF0000 /* If V=1 */ 58 ldmia r0!, {r2-r8,r10} 59 stmia r1!, {r2-r8,r10} 60 ldmia r0!, {r2-r8,r10} 61 stmia r1!, {r2-r8,r10} 62#endif 63#endif 64 bx lr 65 66ENDPROC(relocate_vectors) 67 68/* 69 * void relocate_code(addr_moni) 70 * 71 * This function relocates the monitor code. 72 * 73 * NOTE: 74 * To prevent the code below from containing references with an R_ARM_ABS32 75 * relocation record type, we never refer to linker-defined symbols directly. 76 * Instead, we declare literals which contain their relative location with 77 * respect to relocate_code, and at run time, add relocate_code back to them. 78 */ 79 80ENTRY(relocate_code) 81 ldr r1, =__image_copy_start /* r1 <- SRC &__image_copy_start */ 82 subs r4, r0, r1 /* r4 <- relocation offset */ 83 beq relocate_done /* skip relocation */ 84 ldr r2, =__image_copy_end /* r2 <- SRC &__image_copy_end */ 85 86copy_loop: 87 ldmia r1!, {r10-r11} /* copy from source address [r1] */ 88 stmia r0!, {r10-r11} /* copy to target address [r0] */ 89 cmp r1, r2 /* until source end address [r2] */ 90 blo copy_loop 91 92 /* 93 * fix .rel.dyn relocations 94 */ 95 ldr r2, =__rel_dyn_start /* r2 <- SRC &__rel_dyn_start */ 96 ldr r3, =__rel_dyn_end /* r3 <- SRC &__rel_dyn_end */ 97fixloop: 98 ldmia r2!, {r0-r1} /* (r0,r1) <- (SRC location,fixup) */ 99 and r1, r1, #0xff 100 cmp r1, #R_ARM_RELATIVE 101 bne fixnext 102 103 /* relative fix: increase location by offset */ 104 add r0, r0, r4 105 ldr r1, [r0] 106 add r1, r1, r4 107 str r1, [r0] 108fixnext: 109 cmp r2, r3 110 blo fixloop 111 112relocate_done: 113 114#ifdef __XSCALE__ 115 /* 116 * On xscale, icache must be invalidated and write buffers drained, 117 * even with cache disabled - 4.2.7 of xscale core developer's manual 118 */ 119 mcr p15, 0, r0, c7, c7, 0 /* invalidate icache */ 120 mcr p15, 0, r0, c7, c10, 4 /* drain write buffer */ 121#endif 122 123 /* ARMv4- don't know bx lr but the assembler fails to see that */ 124 125#ifdef __ARM_ARCH_4__ 126 mov pc, lr 127#else 128 bx lr 129#endif 130 131ENDPROC(relocate_code) 132