diff options
Diffstat (limited to 'ldso/ldso/bfin/dl-startup.h')
| -rw-r--r-- | ldso/ldso/bfin/dl-startup.h | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/ldso/ldso/bfin/dl-startup.h b/ldso/ldso/bfin/dl-startup.h new file mode 100644 index 000000000..09f946e9f --- /dev/null +++ b/ldso/ldso/bfin/dl-startup.h @@ -0,0 +1,155 @@ + /* Copyright (C) 2003 Red Hat, Inc. + Contributed by Alexandre Oliva <aoliva@redhat.com> + +This file is part of uClibc. + +uClibc is free software; you can redistribute it and/or modify it +under the terms of the GNU Lesser General Public License as +published by the Free Software Foundation; either version 2.1 of the +License, or (at your option) any later version. + +uClibc 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 +Library General Public License for more details. + +You should have received a copy of the GNU Lesser General Public +License along with uClibc; see the file COPYING.LIB. If not, write to +the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, +USA. */ + +/* Any assembly language/system dependent hacks needed to setup + * boot1.c so it will work as expected and cope with whatever platform + * specific wierdness is needed for this architecture. + + * We override the default _dl_boot function, and replace it with a + * bit of asm. Then call the real _dl_boot function, which is now + * named _dl_boot2. */ + +/* At program start-up, p0 contains a pointer to a + elf32_fdpic_loadmap that describes how the executable was loaded + into memory. p1 contains a pointer to the interpreter (our!) + loadmap, if there is an interpreter, or 0 if we're being run as an + executable. p2 holds a pointer to the interpreter's dynamic + section, if there is an interpreter, or to the executable's dynamic + section, otherwise. If the executable is not dynamic, gr18 is 0. + + We rely on the fact that the linker adds a pointer to the + _GLOBAL_OFFSET_TABLE_ as the last ROFIXUP entry, and that + __self_reloc returns the relocated pointer to us, so that we can + use this value to initialize the PIC register. */ + +__asm__( + " .text\n" \ + " .global __dl_boot\n" \ + " .type __dl_boot,@function\n" \ + "__dl_boot:\n" \ + " call .Lcall\n" \ + ".Lcall:\n" \ + " R4 = RETS;\n" \ + " SP += -32;\n" \ + " R5 = P0;\n" \ + " R6 = P1;\n" \ + " R7 = P2;\n" \ + " R0.L = .Lcall;\n" \ + " R0.H = .Lcall;\n" \ + " R1.L = __ROFIXUP_LIST__;\n" \ + " R1.H = __ROFIXUP_LIST__;\n" \ + " R2.L = __ROFIXUP_END__;\n" \ + " R2.H = __ROFIXUP_END__;\n" \ + " R1 = R1 - R0;\n" \ + " R1 = R1 + R4;\n" \ + " R2 = R2 - R0;\n" \ + " R2 = R2 + R4;\n" \ + " R0 = P1;\n" \ + " CC = R0 == 0;\n" \ + " IF CC R0 = P0;\n" \ + " CALL ___self_reloc;\n" \ + " P3 = R0;\n" \ + " P5 = R0;\n" \ + " R1 = R5;\n" \ + " R2 = R6;\n" \ + " [SP + 12] = R7;\n" \ + " P0 = SP;\n" \ + " P0 += 24;\n" \ + " [SP + 16] = P0;\n" \ + " P0 += 8;\n" \ + " [SP + 20] = P0;\n" \ + " CALL __dl_start;\n" \ + " /* Pass our FINI ptr() to the user in P1 */\n" \ + " R7 = [P5 + __dl_fini@FUNCDESC_GOT17M4];\n" \ + " P4 = [SP + 24];\n" \ + " P3 = [SP + 28];\n" \ + " P0 = R5;\n" \ + " SP += 32;\n" \ + " JUMP (P4);\n" \ + " .size __dl_boot,.-__dl_boot\n" +); + +#define DL_BOOT(X) \ +static void __attribute__ ((used)) \ +_dl_start (Elf32_Addr dl_boot_got_pointer, \ + struct elf32_fdpic_loadmap *dl_boot_progmap, \ + struct elf32_fdpic_loadmap *dl_boot_ldsomap, \ + Elf32_Dyn *dl_boot_ldso_dyn_pointer, \ + struct funcdesc_value *dl_main_funcdesc, \ + X) + +struct elf32_fdpic_loadmap; + +/* + * Get a pointer to the argv array. On many platforms this can be just + * the address if the first argument, on other platforms we need to + * do something a little more subtle here. + */ +#define GET_ARGV(ARGVP, ARGS) ARGVP = (((unsigned long*) ARGS) + 1) + +/* + * Compute the GOT address. On several platforms, we use assembly + * here. on FR-V FDPIC, there's no way to compute the GOT address, + * since the offset between text and data is not fixed, so we arrange + * for the assembly _dl_boot to pass this value as an argument to + * _dl_boot. */ +#define DL_BOOT_COMPUTE_GOT(got) ((got) = dl_boot_got_pointer) + +#define DL_BOOT_COMPUTE_DYN(dpnt, got, load_addr) \ + ((dpnt) = dl_boot_ldso_dyn_pointer) + +/* + * Here is a macro to perform a relocation. This is only used when + * bootstrapping the dynamic loader. RELP is the relocation that we + * are performing, REL is the pointer to the address we are relocating. + * SYMBOL is the symbol involved in the relocation, and LOAD is the + * load address. + */ +#define PERFORM_BOOTSTRAP_RELOC(RELP,REL,SYMBOL,LOAD,SYMTAB) \ + switch(ELF32_R_TYPE((RELP)->r_info)){ \ + case R_BFIN_byte4_data: \ + *(REL) += (SYMBOL); \ + break; \ + case R_BFIN_FUNCDESC_VALUE: \ + { \ + struct funcdesc_value fv = { \ + (void*)((SYMBOL) + *(REL)), \ + (LOAD).got_value \ + }; \ + *(struct funcdesc_value volatile *)(REL) = fv; \ + break; \ + } \ + default: \ + _dl_exit(1); \ + } + +/* + * Transfer control to the user's application, once the dynamic loader + * is done. We return the address of the function's entry point to + * _dl_boot, see boot1_arch.h. + */ +#define START() do { \ + struct elf_resolve *exec_mod = _dl_loaded_modules; \ + dl_main_funcdesc->entry_point = _dl_elf_main; \ + while (exec_mod->libtype != elf_executable) \ + exec_mod = exec_mod->next; \ + dl_main_funcdesc->got_value = exec_mod->loadaddr.got_value; \ + return; \ +} while (0) |