diff options
Diffstat (limited to 'arch/blackfin/lib')
-rw-r--r-- | arch/blackfin/lib/Makefile | 1 | ||||
-rw-r--r-- | arch/blackfin/lib/module.c | 311 |
2 files changed, 312 insertions, 0 deletions
diff --git a/arch/blackfin/lib/Makefile b/arch/blackfin/lib/Makefile index 3f625b77d2..286f138e3c 100644 --- a/arch/blackfin/lib/Makefile +++ b/arch/blackfin/lib/Makefile @@ -14,3 +14,4 @@ obj-y += cpu.o obj-y += flush.o obj-y += interrupt.o obj-y += traps.o +obj-$(CONFIG_MODULE) += module.o diff --git a/arch/blackfin/lib/module.c b/arch/blackfin/lib/module.c new file mode 100644 index 0000000000..a82d0a9137 --- /dev/null +++ b/arch/blackfin/lib/module.c @@ -0,0 +1,311 @@ +/* + * File: arch/blackfin/kernel/module.c + * Based on: + * Author: + * + * Created: + * Description: + * + * Modified: + * Copyright 2004-2006 Analog Devices Inc. + * + * Bugs: Enter bugs at http://blackfin.uclinux.org/ + * + * 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 <common.h> +#include <elf.h> +#include <module.h> +#include <malloc.h> +#include <errno.h> + +/* + * handle arithmetic relocations. + * See binutils/bfd/elf32-bfin.c for more details + */ +#define RELOC_STACK_SIZE 100 +static uint32_t reloc_stack[RELOC_STACK_SIZE]; +static unsigned int reloc_stack_tos; + +#define is_reloc_stack_empty() ((reloc_stack_tos > 0)?0:1) + +static void reloc_stack_push(uint32_t value) +{ + reloc_stack[reloc_stack_tos++] = value; +} + +static uint32_t reloc_stack_pop(void) +{ + return reloc_stack[--reloc_stack_tos]; +} + +static uint32_t reloc_stack_operate(unsigned int oper, struct module *mod) +{ + uint32_t value; + + switch (oper) { + case R_add: + value = reloc_stack[reloc_stack_tos - 2] + + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_sub: + value = reloc_stack[reloc_stack_tos - 2] - + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_mult: + value = reloc_stack[reloc_stack_tos - 2] * + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_div: + value = reloc_stack[reloc_stack_tos - 2] / + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_mod: + value = reloc_stack[reloc_stack_tos - 2] % + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_lshift: + value = reloc_stack[reloc_stack_tos - 2] << + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_rshift: + value = reloc_stack[reloc_stack_tos - 2] >> + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_and: + value = reloc_stack[reloc_stack_tos - 2] & + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_or: + value = reloc_stack[reloc_stack_tos - 2] | + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_xor: + value = reloc_stack[reloc_stack_tos - 2] ^ + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_land: + value = reloc_stack[reloc_stack_tos - 2] && + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_lor: + value = reloc_stack[reloc_stack_tos - 2] || + reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 2; + break; + case R_neg: + value = -reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos--; + break; + case R_comp: + value = ~reloc_stack[reloc_stack_tos - 1]; + reloc_stack_tos -= 1; + break; + default: + printf("module %s: unhandled reloction\n", + mod->name); + return 0; + } + + /* now push the new value back on stack */ + reloc_stack_push(value); + + return value; +} + +int +apply_relocate(Elf_Shdr * sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, struct module *me) +{ + printf("module %s: .rel unsupported\n", me->name); + return -ENOEXEC; +} + +/*************************************************************************/ +/* FUNCTION : apply_relocate_add */ +/* ABSTRACT : Blackfin specific relocation handling for the loadable */ +/* modules. Modules are expected to be .o files. */ +/* Arithmetic relocations are handled. */ +/* We do not expect LSETUP to be split and hence is not */ +/* handled. */ +/* R_byte and R_byte2 are also not handled as the gas */ +/* does not generate it. */ +/*************************************************************************/ +int +apply_relocate_add(Elf_Shdr * sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *mod) +{ + unsigned int i; + unsigned short tmp; + Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; + Elf32_Sym *sym; + uint32_t *location32; + uint16_t *location16; + uint32_t value; + + debug("Applying relocate section %u to %u\n", relsec, + sechdrs[relsec].sh_info); + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + /* This is where to make the change */ + location16 = + (uint16_t *) (sechdrs[sechdrs[relsec].sh_info].sh_addr + + rel[i].r_offset); + location32 = (uint32_t *) location16; + /* This is the symbol it is referring to. Note that all + undefined symbols have been resolved. */ + sym = (Elf32_Sym *) sechdrs[symindex].sh_addr + + ELF32_R_SYM(rel[i].r_info); + if (is_reloc_stack_empty()) { + value = sym->st_value; + } else { + value = reloc_stack_pop(); + } + value += rel[i].r_addend; + debug("location is %x, value is %x type is %d \n", + (unsigned int) location32, value, + ELF32_R_TYPE(rel[i].r_info)); + + switch (ELF32_R_TYPE(rel[i].r_info)) { + + case R_pcrel24: + case R_pcrel24_jump_l: + /* Add the value, subtract its postition */ + location16 = + (uint16_t *) (sechdrs[sechdrs[relsec].sh_info]. + sh_addr + rel[i].r_offset - 2); + location32 = (uint32_t *) location16; + value -= (uint32_t) location32; + value >>= 1; + debug("value is %x, before %x-%x after %x-%x\n", value, + *location16, *(location16 + 1), + (*location16 & 0xff00) | (value >> 16 & 0x00ff), + value & 0xffff); + *location16 = + (*location16 & 0xff00) | (value >> 16 & 0x00ff); + *(location16 + 1) = value & 0xffff; + break; + case R_pcrel12_jump: + case R_pcrel12_jump_s: + value -= (uint32_t) location32; + value >>= 1; + *location16 = (value & 0xfff); + break; + case R_pcrel10: + value -= (uint32_t) location32; + value >>= 1; + *location16 = (value & 0x3ff); + break; + case R_luimm16: + debug("before %x after %x\n", *location16, + (value & 0xffff)); + tmp = (value & 0xffff); + *location16 = tmp; + break; + case R_huimm16: + debug("before %x after %x\n", *location16, + ((value >> 16) & 0xffff)); + tmp = ((value >> 16) & 0xffff); + *location16 = tmp; + break; + case R_rimm16: + *location16 = (value & 0xffff); + break; + case R_byte4_data: + debug("before %x after %x\n", *location32, value); + *location32 = value; + break; + case R_push: + reloc_stack_push(value); + break; + case R_const: + reloc_stack_push(rel[i].r_addend); + break; + case R_add: + case R_sub: + case R_mult: + case R_div: + case R_mod: + case R_lshift: + case R_rshift: + case R_and: + case R_or: + case R_xor: + case R_land: + case R_lor: + case R_neg: + case R_comp: + reloc_stack_operate(ELF32_R_TYPE(rel[i].r_info), mod); + break; + default: + printf("module %s: Unknown relocation: %u\n", + mod->name, ELF32_R_TYPE(rel[i].r_info)); + return -ENOEXEC; + } + } + return 0; +} + +#if 0 +int +module_finalize(const Elf_Ehdr * hdr, + const Elf_Shdr * sechdrs, struct module *mod) +{ + unsigned int i, strindex = 0, symindex = 0; + char *secstrings; + + secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + + for (i = 1; i < hdr->e_shnum; i++) { + /* Internal symbols and strings. */ + if (sechdrs[i].sh_type == SHT_SYMTAB) { + symindex = i; + strindex = sechdrs[i].sh_link; + } + } + + for (i = 1; i < hdr->e_shnum; i++) { + const char *strtab = (char *)sechdrs[strindex].sh_addr; + unsigned int info = sechdrs[i].sh_info; + + /* Not a valid relocation section? */ + if (info >= hdr->e_shnum) + continue; + + if ((sechdrs[i].sh_type == SHT_RELA) && + ((strcmp(".rela.l1.text", secstrings + sechdrs[i].sh_name) == 0) || + ((strcmp(".rela.text", secstrings + sechdrs[i].sh_name) == 0) && + (hdr->e_flags & FLG_CODE_IN_L1)))) { + apply_relocate_add((Elf_Shdr *) sechdrs, strtab, + symindex, i, mod); + } + } + return 0; +} +#endif + |