Ok, here's an updated version.

--------------------------------8<------------------------------

This adds aarch64 support for relocating binaries linked with -pie.

Support is integrated into the already exisiting
relocate_to_current_adr() function which is now used for both arm32
and aarch64.

Signed-off-by: Sascha Hauer <s.ha...@pengutronix.de>
---
 arch/arm/cpu/common.c    | 69 ++++++++++++++++++++++++++++++++++++++----------
 arch/arm/cpu/setupc_64.S | 60 +++++++++++++++++++++++++++++++++++++++++
 common/Kconfig           |  2 +-
 3 files changed, 116 insertions(+), 15 deletions(-)

diff --git a/arch/arm/cpu/common.c b/arch/arm/cpu/common.c
index 7c07d00c1b..00ce3efb2f 100644
--- a/arch/arm/cpu/common.c
+++ b/arch/arm/cpu/common.c
@@ -17,6 +17,7 @@
 
 #include <common.h>
 #include <init.h>
+#include <elf.h>
 #include <linux/sizes.h>
 #include <asm/system_info.h>
 #include <asm/barebox-arm.h>
@@ -24,42 +25,82 @@
 #include <asm-generic/memory_layout.h>
 #include <asm/sections.h>
 #include <asm/cache.h>
+#include <debug_ll.h>
+
+#define R_ARM_RELATIVE 23
+#define R_AARCH64_RELATIVE 1027
 
 /*
  * relocate binary to the currently running address
  */
 void relocate_to_current_adr(void)
 {
-       uint32_t offset;
-       uint32_t *dstart, *dend, *dynsym, *dynend;
+       unsigned long offset, offset_var;
+       unsigned long __maybe_unused *dynsym, *dynend;
+       void *dstart, *dend;
 
        /* Get offset between linked address and runtime address */
        offset = get_runtime_offset();
+       offset_var = global_variable_offset();
+
+       dstart = (void *)__rel_dyn_start + offset_var;
+       dend = (void *)__rel_dyn_end + offset_var;
 
-       dstart = (void *)__rel_dyn_start + offset;
-       dend = (void *)__rel_dyn_end + offset;
+#if defined(CONFIG_CPU_64)
+       while (dstart < dend) {
+               struct elf64_rela *rel = dstart;
 
-       dynsym = (void *)__dynsym_start + offset;
-       dynend = (void *)__dynsym_end + offset;
+               if (ELF64_R_TYPE(rel->r_info) == R_AARCH64_RELATIVE) {
+                       unsigned long *fixup = (unsigned long *)(rel->r_offset 
+ offset);
+
+                       *fixup = rel->r_addend + offset;
+               } else {
+                       putc_ll('>');
+                       puthex_ll(rel->r_info);
+                       putc_ll(' ');
+                       puthex_ll(rel->r_offset);
+                       putc_ll(' ');
+                       puthex_ll(rel->r_addend);
+                       putc_ll('\n');
+                       panic("");
+               }
+
+               dstart += sizeof(*rel);
+       }
+#elif defined(CONFIG_CPU_32)
+       dynsym = (void *)__dynsym_start + offset_var;
+       dynend = (void *)__dynsym_end + offset_var;
 
        while (dstart < dend) {
-               uint32_t *fixup = (uint32_t *)(*dstart + offset);
-               uint32_t type = *(dstart + 1);
+               struct elf32_rel *rel = dstart;
+
+               if (ELF32_R_TYPE(rel->r_info) == R_ARM_RELATIVE) {
+                       unsigned long *fixup = (unsigned long *)(rel->r_offset 
+ offset);
 
-               if ((type & 0xff) == 0x17) {
                        *fixup = *fixup + offset;
-               } else {
-                       int index = type >> 8;
-                       uint32_t r = dynsym[index * 4 + 1];
+
+                       rel->r_offset += offset;
+               } else if (ELF32_R_TYPE(rel->r_info) == R_ARM_ABS32) {
+                       unsigned long r = dynsym[ELF32_R_SYM(rel->r_info) * 4 + 
1];
+                       unsigned long *fixup = (unsigned long *)(rel->r_offset 
+ offset);
 
                        *fixup = *fixup + r + offset;
+               } else {
+                       putc_ll('>');
+                       puthex_ll(rel->r_info);
+                       putc_ll(' ');
+                       puthex_ll(rel->r_offset);
+                       putc_ll('\n');
+                       panic("");
                }
 
-               *dstart += offset;
-               dstart += 2;
+               dstart += sizeof(*rel);
        }
 
        memset(dynsym, 0, (unsigned long)dynend - (unsigned long)dynsym);
+#else
+#error "Architecture not specified"
+#endif
 
        arm_early_mmu_cache_flush();
        icache_invalidate();
diff --git a/arch/arm/cpu/setupc_64.S b/arch/arm/cpu/setupc_64.S
index 3515854784..13f19fcc4d 100644
--- a/arch/arm/cpu/setupc_64.S
+++ b/arch/arm/cpu/setupc_64.S
@@ -16,3 +16,63 @@ ENTRY(setup_c)
        mov     x30, x15
        ret
 ENDPROC(setup_c)
+
+/*
+ * void relocate_to_adr(unsigned long targetadr)
+ *
+ * Copy binary to targetadr, relocate code and continue
+ * executing at new address.
+ */
+.section .text.relocate_to_adr
+ENTRY(relocate_to_adr)
+                                       /* x0: target address */
+
+       stp     x19, x20, [sp, #-16]!
+       stp     x21, x22, [sp, #-16]!
+
+       mov     x19, lr
+
+       mov     x21, x0
+
+       bl      get_runtime_offset
+       mov     x5, x0
+
+       ldr     x0, =_text
+       mov     x20, x0
+
+       add     x1, x0, x5              /* x1: from address */
+
+       cmp     x1, x21                 /* already at correct address? */
+       beq     1f                      /* yes, skip copy to new address */
+
+       ldr     x2, =__bss_start
+
+       sub     x2, x2, x0              /* x2: size */
+       mov     x0, x21                 /* x0: target */
+
+       /* adjust return address */
+       sub     x19, x19, x1            /* sub address where we are actually 
running */
+       add     x19, x19, x0            /* add address where we are going to 
run */
+
+       bl      memcpy                  /* copy binary */
+
+#ifdef CONFIG_MMU
+       bl      arm_early_mmu_cache_flush
+#endif
+       mov     x0,#0
+       ic      ivau, x0        /* flush icache */
+
+       ldr     x0,=1f
+       sub     x0, x0, x20
+       add     x0, x0, x21
+       br      x0                      /* jump to relocated address */
+1:
+       bl      relocate_to_current_adr /* relocate binary */
+
+       mov     lr, x19
+
+       ldp     x21, x22, [sp], #16
+       ldp     x19, x20, [sp], #16
+       ret
+
+ENDPROC(relocate_to_adr)
diff --git a/common/Kconfig b/common/Kconfig
index af71d6888a..b7000c4d73 100644
--- a/common/Kconfig
+++ b/common/Kconfig
@@ -344,7 +344,7 @@ config KALLSYMS
          This is useful to print a nice backtrace when an exception occurs.
 
 config RELOCATABLE
-       depends on PPC || (ARM && !CPU_V8)
+       depends on PPC || ARM
        bool "generate relocatable barebox binary"
        help
          A non relocatable barebox binary will run at it's compiled in
-- 
2.16.1

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

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