2 * relocate - common relocation function for ARM U-Boot
4 * Copyright (c) 2013 Albert ARIBAUD <albert.u.boot@aribaud.net>
6 * SPDX-License-Identifier: GPL-2.0+
9 #include <asm-offsets.h>
11 #include <linux/linkage.h>
14 * void relocate_code(addr_moni)
16 * This function relocates the monitor code.
19 * To prevent the code below from containing references with an R_ARM_ABS32
20 * relocation record type, we never refer to linker-defined symbols directly.
21 * Instead, we declare literals which contain their relative location with
22 * respect to relocate_code, and at run time, add relocate_code back to them.
26 ldr r1, =__image_copy_start /* r1 <- SRC &__image_copy_start */
27 subs r4, r0, r1 /* r4 <- relocation offset */
28 beq relocate_done /* skip relocation */
29 ldr r2, =__image_copy_end /* r2 <- SRC &__image_copy_end */
32 ldmia r1!, {r10-r11} /* copy from source address [r1] */
33 stmia r0!, {r10-r11} /* copy to target address [r0] */
34 cmp r1, r2 /* until source end address [r2] */
38 * fix .rel.dyn relocations
40 ldr r2, =__rel_dyn_start /* r2 <- SRC &__rel_dyn_start */
41 ldr r3, =__rel_dyn_end /* r3 <- SRC &__rel_dyn_end */
43 ldmia r2!, {r0-r1} /* (r0,r1) <- (SRC location,fixup) */
45 cmp r1, #23 /* relative fixup? */
48 /* relative fix: increase location by offset */
58 * Relocate the exception vectors
60 #ifdef CONFIG_HAS_VBAR
62 * If the ARM processor has the security extensions,
63 * use VBAR to relocate the exception vectors.
65 ldr r0, [r9, #GD_RELOCADDR] /* r0 = gd->relocaddr */
66 mcr p15, 0, r0, c12, c0, 0 /* Set VBAR */
69 * Copy the relocated exception vectors to the
71 * CP15 c1 V bit gives us the location of the vectors:
72 * 0x00000000 or 0xFFFF0000.
74 ldr r0, [r9, #GD_RELOCADDR] /* r0 = gd->relocaddr */
75 mrc p15, 0, r2, c1, c0, 0 /* V bit (bit[13]) in CP15 c1 */
76 ands r2, r2, #(1 << 13)
77 ldreq r1, =0x00000000 /* If V=0 */
78 ldrne r1, =0xFFFF0000 /* If V=1 */
79 ldmia r0!, {r2-r8,r10}
80 stmia r1!, {r2-r8,r10}
81 ldmia r0!, {r2-r8,r10}
82 stmia r1!, {r2-r8,r10}
89 * On xscale, icache must be invalidated and write buffers drained,
90 * even with cache disabled - 4.2.7 of xscale core developer's manual
92 mcr p15, 0, r0, c7, c7, 0 /* invalidate icache */
93 mcr p15, 0, r0, c7, c10, 4 /* drain write buffer */
96 /* ARMv4- don't know bx lr but the assembler fails to see that */
104 ENDPROC(relocate_code)