/*
   * arch/score/kernel/module.c
   *
   * Score Processor version.
   *
   * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
   *  Chen Liqin <liqin.chen@sunplusct.com>
   *  Lennox Wu <lennox.wu@sunplusct.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, see the file COPYING, or write
   * to the Free Software Foundation, Inc.,
   * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
   */

  #include <linux/moduleloader.h>

  #include <linux/module.h>
  #include <linux/vmalloc.h>

  int apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
  		unsigned int symindex, unsigned int relindex,
  		struct module *me)
  {
  	Elf32_Shdr *symsec = sechdrs + symindex;
  	Elf32_Shdr *relsec = sechdrs + relindex;
  	Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
  	Elf32_Rel *rel = (void *)relsec->sh_addr;
  	unsigned int i;
  
  	for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
  		unsigned long loc;
  		Elf32_Sym *sym;

  		s32 r_offset;

  		r_offset = ELF32_R_SYM(rel->r_info);
  		if ((r_offset < 0) ||
  		    (r_offset > (symsec->sh_size / sizeof(Elf32_Sym)))) {

  			printk(KERN_ERR "%s: bad relocation, section %d reloc %d
  ",
  				me->name, relindex, i);
  				return -ENOEXEC;
  		}

  		sym = ((Elf32_Sym *)symsec->sh_addr) + r_offset;

  
  		if ((rel->r_offset < 0) ||
  		    (rel->r_offset > dstsec->sh_size - sizeof(u32))) {
  			printk(KERN_ERR "%s: out of bounds relocation, "
  				"section %d reloc %d offset %d size %d
  ",
  				me->name, relindex, i, rel->r_offset,
  				dstsec->sh_size);
  			return -ENOEXEC;
  		}
  
  		loc = dstsec->sh_addr + rel->r_offset;
  		switch (ELF32_R_TYPE(rel->r_info)) {
  		case R_SCORE_NONE:
  			break;
  		case R_SCORE_ABS32:
  			*(unsigned long *)loc += sym->st_value;
  			break;
  		case R_SCORE_HI16:
  			break;
  		case R_SCORE_LO16: {
  			unsigned long hi16_offset, offset;
  			unsigned long uvalue;
  			unsigned long temp, temp_hi;
  			temp_hi = *((unsigned long *)loc - 1);
  			temp = *(unsigned long *)loc;
  
  			hi16_offset = (((((temp_hi) >> 16) & 0x3) << 15) |
  					((temp_hi) & 0x7fff)) >> 1;
  			offset = ((temp >> 16 & 0x03) << 15) |
  					((temp & 0x7fff) >> 1);
  			offset = (hi16_offset << 16) | (offset & 0xffff);
  			uvalue = sym->st_value + offset;
  			hi16_offset = (uvalue >> 16) << 1;
  
  			temp_hi = ((temp_hi) & (~(0x37fff))) |
  					(hi16_offset & 0x7fff) |
  					((hi16_offset << 1) & 0x30000);
  			*((unsigned long *)loc - 1) = temp_hi;
  
  			offset = (uvalue & 0xffff) << 1;
  			temp = (temp & (~(0x37fff))) | (offset & 0x7fff) |
  				((offset << 1) & 0x30000);
  			*(unsigned long *)loc = temp;
  			break;
  		}
  		case R_SCORE_24: {
  			unsigned long hi16_offset, offset;
  			unsigned long uvalue;
  			unsigned long temp;
  
  			temp = *(unsigned long *)loc;
  			offset = (temp & 0x03FF7FFE);
  			hi16_offset = (offset & 0xFFFF0000);
  			offset = (hi16_offset | ((offset & 0xFFFF) << 1)) >> 2;
  
  			uvalue = (sym->st_value + offset) >> 1;
  			uvalue = uvalue & 0x00ffffff;
  
  			temp = (temp & 0xfc008001) |
  				((uvalue << 2) & 0x3ff0000) |
  				((uvalue & 0x3fff) << 1);
  			*(unsigned long *)loc = temp;
  			break;
  		}
  		default:
  			printk(KERN_ERR "%s: unknown relocation: %u
  ",
  				me->name, ELF32_R_TYPE(rel->r_info));
  			return -ENOEXEC;
  		}
  	}
  
  	return 0;
  }
  
  int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
  		unsigned int symindex, unsigned int relsec,
  		struct module *me)
  {

  	/* Non-standard return value... most other arch's return -ENOEXEC
  	 * for an unsupported relocation variant
  	 */

  	return 0;
  }
  
  /* Given an address, look for it in the module exception tables. */
  const struct exception_table_entry *search_module_dbetables(unsigned long addr)
  {

  	return NULL;

  }