git.sur5r.net Git - u-boot/blob - arch/arc/lib/relocate.c

   1 /*
   2  * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <elf.h>
   9 #include <asm-generic/sections.h>
  10
  11 extern ulong __image_copy_start;
  12 extern ulong __ivt_end;
  13
  14 DECLARE_GLOBAL_DATA_PTR;
  15
  16 int copy_uboot_to_ram(void)
  17 {
  18         size_t len = (size_t)&__image_copy_end - (size_t)&__image_copy_start;
  19
  20         if (gd->flags & GD_FLG_SKIP_RELOC)
  21                 return 0;
  22
  23         memcpy((void *)gd->relocaddr, (void *)&__image_copy_start, len);
  24
  25         return 0;
  26 }
  27
  28 int clear_bss(void)
  29 {
  30         ulong dst_addr = (ulong)&__bss_start + gd->reloc_off;
  31         size_t len = (size_t)&__bss_end - (size_t)&__bss_start;
  32
  33         memset((void *)dst_addr, 0x00, len);
  34
  35         return 0;
  36 }
  37
  38 /*
  39  * Base functionality is taken from x86 version with added ARC-specifics
  40  */
  41 int do_elf_reloc_fixups(void)
  42 {
  43         Elf32_Rela *re_src = (Elf32_Rela *)(&__rel_dyn_start);
  44         Elf32_Rela *re_end = (Elf32_Rela *)(&__rel_dyn_end);
  45
  46         if (gd->flags & GD_FLG_SKIP_RELOC)
  47                 return 0;
  48
  49         debug("Section .rela.dyn is located at %08x-%08x\n",
  50               (unsigned int)re_src, (unsigned int)re_end);
  51
  52         Elf32_Addr *offset_ptr_rom, *last_offset = NULL;
  53         Elf32_Addr *offset_ptr_ram;
  54
  55         do {
  56                 /* Get the location from the relocation entry */
  57                 offset_ptr_rom = (Elf32_Addr *)re_src->r_offset;
  58
  59                 /* Check that the location of the relocation is in .text */
  60                 if (offset_ptr_rom >= (Elf32_Addr *)&__image_copy_start &&
  61                     offset_ptr_rom > last_offset) {
  62                         unsigned int val;
  63                         /* Switch to the in-RAM version */
  64                         offset_ptr_ram = (Elf32_Addr *)((ulong)offset_ptr_rom +
  65                                                         gd->reloc_off);
  66
  67                         debug("Patching value @ %08x (relocated to %08x)\n",
  68                               (unsigned int)offset_ptr_rom,
  69                               (unsigned int)offset_ptr_ram);
  70
  71                         /*
  72                          * Use "memcpy" because target location might be
  73                          * 16-bit aligned on ARC so we may need to read
  74                          * byte-by-byte. On attempt to read entire word by
  75                          * CPU throws an exception
  76                          */
  77                         memcpy(&val, offset_ptr_ram, sizeof(int));
  78
  79 #ifdef __LITTLE_ENDIAN__
  80                         /* If location in ".text" section swap value */
  81                         if ((unsigned int)offset_ptr_rom <
  82                             (unsigned int)&__ivt_end)
  83                                 val = (val << 16) | (val >> 16);
  84 #endif
  85
  86                         /* Check that the target points into executable */
  87                         if (val >= (unsigned int)&__image_copy_start && val <=
  88                             (unsigned int)&__image_copy_end) {
  89                                 val += gd->reloc_off;
  90 #ifdef __LITTLE_ENDIAN__
  91                                 /* If location in ".text" section swap value */
  92                                 if ((unsigned int)offset_ptr_rom <
  93                                     (unsigned int)&__ivt_end)
  94                                         val = (val << 16) | (val >> 16);
  95 #endif
  96                                 memcpy(offset_ptr_ram, &val, sizeof(int));
  97                         }
  98                 }
  99                 last_offset = offset_ptr_rom;
 100
 101         } while (++re_src < re_end);
 102
 103         return 0;
 104 }