arc: add library functions

[people/ms/u-boot.git] / arch / arc / lib / relocate.c

diff --git a/arch/arc/lib/relocate.c b/arch/arc/lib/relocate.c
new file mode 100644 (file)
index 0000000..956aa14
--- /dev/null
+++ b/arch/arc/lib/relocate.c
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier:    GPL-2.0+
+ */
+
+#include <common.h>
+#include <elf.h>
+#include <asm/sections.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * Base functionality is taken from x86 version with added ARC-specifics
+ */
+int do_elf_reloc_fixups(void)
+{
+       Elf32_Rela *re_src = (Elf32_Rela *)(&__rel_dyn_start);
+       Elf32_Rela *re_end = (Elf32_Rela *)(&__rel_dyn_end);
+
+       Elf32_Addr *offset_ptr_rom, *last_offset = NULL;
+       Elf32_Addr *offset_ptr_ram;
+
+       do {
+               /* Get the location from the relocation entry */
+               offset_ptr_rom = (Elf32_Addr *)re_src->r_offset;
+
+               /* Check that the location of the relocation is in .text */
+               if (offset_ptr_rom >= (Elf32_Addr *)CONFIG_SYS_TEXT_BASE &&
+                   offset_ptr_rom > last_offset) {
+                       unsigned int val;
+                       /* Switch to the in-RAM version */
+                       offset_ptr_ram = (Elf32_Addr *)((ulong)offset_ptr_rom +
+                                                       gd->reloc_off);
+
+                       /*
+                        * Use "memcpy" because target location might be
+                        * 16-bit aligned on ARC so we may need to read
+                        * byte-by-byte. On attempt to read entire word by
+                        * CPU throws an exception
+                        */
+                       memcpy(&val, offset_ptr_ram, sizeof(int));
+
+                       /* If location in ".text" section swap value */
+                       if ((unsigned int)offset_ptr_rom <
+                           (unsigned int)&__text_end)
+                               val = (val << 16) | (val >> 16);
+
+                       /* Check that the target points into .text */
+                       if (val >= CONFIG_SYS_TEXT_BASE && val <=
+                           (unsigned int)&__bss_end) {
+                               val += gd->reloc_off;
+                               /* If location in ".text" section swap value */
+                               if ((unsigned int)offset_ptr_rom <
+                                   (unsigned int)&__text_end)
+                                       val = (val << 16) | (val >> 16);
+                               memcpy(offset_ptr_ram, &val, sizeof(int));
+                       } else {
+                               debug("   %p: rom reloc %x, ram %p, value %x, limit %x\n",
+                                     re_src, re_src->r_offset, offset_ptr_ram,
+                                     val, (unsigned int)&__bss_end);
+                       }
+               } else {
+                       debug("   %p: rom reloc %x, last %p\n", re_src,
+                             re_src->r_offset, last_offset);
+               }
+               last_offset = offset_ptr_rom;
+
+       } while (++re_src < re_end);
+
+       return 0;
+}